Artículos científicos

«Carcharodontosauridae forms a clade of medium-to very large-sized (6–14 m long) allosauroid theropods mostly restricted to the Early and mid-Cretaceous with an almost global distribution, and characterized by deep and narrow ornamented skulls and strongly compressed ziphodont teeth. In Brazil, the carcharodontosaurid fossil record is limited to shed teeth and isolated postcranial elements from the Aptian-Cenomanian deposits of the eastern part of the country. Here we describe and identify a shed tooth from a little-known outcrop of the Early Cretaceous (Aptian-Albian) Itapecuru Formation of the Maranhão State, northeastern Brazil. Although some teeth have already been reported from the Aptian-Albian deposits of this unit, this specimen represents the first isolated dental material from the Parnaíba Basin that can be confidently assigned to a carcharodontosaurid through cladistic and morphometric techniques, but also based on a systematic study. The results of the herein conducted study suggest that the specimen belongs to a carcharodontosaurine closely related to the Patagonian taxa Giganotosaurus and Mapusaurus, which are younger in age. Although the specimen is closely related to the abovementioned Patagonian taxa, the faunal composition of the Parnaíba Basin seems to be more similar to that of North Africa. Nevertheless, further collecting efforts are needed in these localities to find skeletal carcharodontosaurid remains and to broaden the comparative base for the identification of theropod dentition.»

«La cuenca superior del Río Bermejo alberga una gran diversidad de peces representada por especies endémicas, fauna compartida entre las cuencas de los ríos Paraguay y Amazonas, y por elementos de la cuenca del Río Paraná. En expediciones recientes en la zona, varios especímenes de una especie no descripta de Ernstichthys fueron colectados en cuatro localidades distintas en el Noroeste de Argentina, los cuales son descriptos aquí. La nueva especie, Ernstichthys casalinuovoi, se distingue de las restantes especies del género por presentar una combinación de caracteres que incluyen el número de placas laterales en el cuerpo, la forma de la segunda placa anterior a la aleta anal, la presencia de una barbilla rictal, el patrón de coloración, el número de vértebras totales, la barbilla maxilar no dividida, y el número de ganchos en el margen posterior de la espina de la aleta pectoral. El gran lote utilizado para describir Ernstichthys casalinuovoi nos permitió detectar caracteres que conviene tratar con cuidado en la descripción de especies pertenecientes a Ernstichthys, como el número de ganchos en el margen posterior de la espina de la aleta pectoral o la superposición entre elementos óseos en el pedúnculo caudal, dado que podrían variar según su ontogenia. Las nuevas especies aquí descritas representan la quinta especie del género y el primer registro de Ernstichthys y Hoplomyzontinae en Argentina.»

«The sacroiliac articulation in anurans enables locomotion, including burrowing, swimming, jumping, and walking, by facilitating pelvic rotation and sliding. The hylid tribe Scinaxini comprises 134 Neotropical treefrogs divided into three genera: Julianus, Ololygon, and Scinax. The osteological elements of the sacroiliac articulation are well studied within the tribe, with Julianus having distinctive sacral diapophyses and sesamoids. Notably, the species J. camposseabrai has a medially elongated sesamoid, about three times its width in length, along with a short sacral diapophysis—a unique combination among anurans. However, information on the associated musculature in the tribe remains limited, restricting our understanding of this unique morphology. This knowledge gap prompted a detailed investigation of the musculature of the sacroiliac articulation in this clade of treefrogs. We revisited the osteology of the sacroiliac articulation and described its muscles in nine species of Scinaxini, including J. camposseabrai and J. pinimus. Our results showed that the origin and insertion of the muscles are largely conserved across the tribe, but variations exist in the orientation of the m. coccygeosacralis and the degree of separation between slips of the m. iliolumbaris. The species of Julianus have a unique sacroiliac osteo-muscular configuration, particularly J. camposseabrai, which is distinct from any previously described in anurans." »

«En las ranas del género Telmatobius, la transición acuática se asocia a ojos más pequeños y frontales, y cápsulas óticas mayores, sugiriendo compensación sensorial»

«Relevamos la distribución taxonómica de una estructura única de los renacuajos, los dientes labiales queratinizados del aparato bucal, y discutimos cómo los patrones de desarrollo son cruciales para interpretar su diversidad. »

«Ecomorphology examines how species' morphology adapt to their environments, providing insights into biodiversity and evolution. This field relies on three main components: a morphological matrix, an ecological matrix, and phylogeny. A major challenge in contemporary anuran ecomorphology is constructing the ecological matrix, as categorizing species' ecological roles lacks a standardized methodology, leading to inconsistencies across studies and complicating comparisons. In this study, we discuss the challenges of systematizing criteria for constructing the ecological matrix in anurans. To this end, we conducted a literature search, focusing on studies that consider microhabitats as ecological categories and locomotor abilities, using relevant keywords to the topic. A total of 31 studies from the last 46 years were selected for analysis, and information was extracted on the following aspects: analyzed species; microhabitat and locomotor mode categories; and whether or not own criteria for assigning ecological categories (i.e., microhabitat and locomotor modes) were specified. The analyzed studies reveal a high degree of consistency in the assignment of ecological categories for microhabitat classification but not for locomotor modes designation. The main discrepancies occur in the burrowing and/or fossorial categories, as well as climbing. Interestingly, these categories appear both as microhabitats and as locomotor modes. Key criteria include direct field observations and assignments based on primary literature sources. The variability in category assignments and data collection criteria underscores the need to develop more standardized protocols for ecological categorization to improve the accuracy and reproducibility of ecomorphological studies.»

«Epidermal scales in sauropsids perform a wide array of biological functions, which can relate to their shape and size. Accordingly, growth-related changes in scale morphology may reflect distinct functions between juvenile and adult individuals, such as use in mating interactions. Such patterns are poorly explored in both extant reptiles and non-avian dinosaurs, limiting functional interpretations. Here, we investigate scale growth in the ornithischian ceratopsid Chasmosaurus belli and hadrosaurid Prosaurolophus maximus by comparing scale morphologies between juveniles and adults of each taxon. Scale shape is generally consistent across growth stages in both taxa, and changes in C. belli feature scale length cannot reject isometry. However, there is a greater increase in C. belli feature scale width. In practical terms, the magnitude of these size differences rejects the hypothesis that feature scale morphology played a role in mating interactions, suggesting instead that their size was largely non-adaptive. To contextualise the patterns in the sampled dinosaurs, we assessed scale growth and allometry using an ecologically diverse sample of eight extant reptile species belonging to Crocodylidae, Scincidae, Elapidae and Pythonidae. While isometry is the overall most frequent pattern of scale growth in our sample of extant reptiles, most species demonstrate positive scale allometry in at least one area of their bodies, which is likely a response to changing body proportions. Scale shapes in the studied extant species, as in both dinosaurs, are largely retained through growth. This study provides the first detailed assessment of skin growth in non-avian dinosaurs, supporting morphological stasis in the growth of most of their scales.»

«Conocemos los renacuajos de menos de la mitad de las casi 7800 especies de ranas y sapos. En este trabajo identificamos áreas prioritarias a nivel global, donde se concentra la mayor diversidad taxonómica y putativamente funcional de estas larvas desconocidas, apuntando a investigaciones estratégicas en contextos de conservación.»

«The Kem Kem Group of Southeastern Morocco, North Africa, is well known for theropod remains, especially isolated teeth. Here, a collection of isolated theropod teeth is assessed for diversity using a combination of linear discriminant, phylogenetic, and machine learning analyses for the first time. The results confirm earlier studies on Kem Kem theropod diversity, with teeth referred to Abelisauridae, Spinosaurinae, and Carcharodontosauridae. A single tooth is ascribed to a non-abelisauroid ceratosaur or a megaraptoran and may represent the enigmatic averostran Deltadromeus. Spinosaurine teeth are clearly differentiated by all three methodologies, whereas abelisaurid and carcharodontosaurid teeth could only be distinguished by the machine learning and phylogenetic analyses. This study shows that a combination of independent methods is most effective at providing strong evidence on theropod dental diversity in a particular assemblage, and that cladistic and machine learning analyses are the most reliable approaches to identify isolated dinosaur teeth. The methodology used here is likely to yield results in other dinosaur assemblages where isolated teeth are more abundant than body fossils.»

«The Kem Kem Group of Southeastern Morocco, North Africa, is well known for theropod remains, especially isolated teeth. Here, a collection of isolated theropod teeth is assessed for diversity using a combination of linear discriminant, phylogenetic, and machine learning analyses for the first time. The results confirm earlier studies on Kem Kem theropod diversity, with teeth referred to Abelisauridae, Spinosaurinae, and Carcharodontosauridae. A single tooth is ascribed to a non-abelisauroid ceratosaur or a megaraptoran and may represent the enigmatic averostran Deltadromeus. Spinosaurine teeth are clearly differentiated by all three methodologies, whereas abelisaurid and carcharodontosaurid teeth could only be distinguished by the machine learning and phylogenetic analyses. This study shows that a combination of independent methods is most effective at providing strong evidence on theropod dental diversity in a particular assemblage, and that cladistic and machine learning analyses are the most reliable approaches to identify isolated dinosaur teeth. The methodology used here is likely to yield results in other dinosaur assemblages where isolated teeth are more abundant than body fossils.»

«Noasaurus leali is a small (~2 m) carnivorous theropod and the nominal genus of the clade Noasauridae, one of the two radiations of abelisauroid ceratosaurs predominantly present in the Southern Hemisphere during the Mesozoic. This eponymous theropod from the Maastrichtian Lecho Formation of Salta, Argentina, is known from an incomplete skeleton of which the strongly curved manual ungual is the most peculiar element. We here provide for the first time a comprehensive description of the holotypic specimens of Noasaurus, whose phylogenetic position was explored using three independent datamatrices on theropod relationships. This species is diagnosed by several apomorphies such as a dorsal ridge in the maxillary fossa, a strongly arched quadrate, a cervical neural arch with anterior epipophyseal prongs, and a manual ungual with a subtriangular flexor fossa delimited by a V-shaped ridge. Results of the phylogenetic analyses recovered Noasaurus closely related to Velocisaurus, Masiakasaurus, and Laevisuchus, which together form a Late Cretaceous radiation of small-bodied noasaurids restricted to the Southern Hemisphere. The peculiar morphology of the lateral dentition and manual unguals suggests that Noasaurus was an opportunistic carnivore feeding on small prey items and a possible piscivore gaffing fish with its specialized hand claws.»

«A new genus of mygalomorph spider Ekapa gen. nov., is described from South Africa. The new genus was formed to include the species Hermacha curvipes Purcell, 1902 and Hermacha nigra Tucker, 1917. These species are synonymized based on their somatic similarities, such as fovea shape, cheliceral teeth distribution, ocular pattern, presence of preening combs, and their close geographic distribution. The new genus proposed is distinguished by the presence of a projection in the retroventral side of the palpal tibia in males, together with a distinctive copulatory bulb shape; and in females by the shape of their spermathecae, with a high base and apical stalks that open into oval apical receptacles.»

«A new species of the poorly known mygalomorph genus Strophaeus Ausserer, 1875 is described. The new species, Strophaeus quillacinga sp. nov., is described from Nariño, Colombia. It represents the first record of Strophaeus from Colombia, with the genus previously only known from Peru, Brazil, and Panama. This species can be distinguished from other known female congeners by the presence of a higher number of spines on the rastellum and the abdomen dorsally mottled.»

«Phylogenetic inference, which involves time-consuming calculations, is a field where parallelization can speed up the resolution of many problems. TNT (a widely used program for phylogenetic analysis under parsimony) allows parallelization under the PVM system (Parallel Virtual Machine). However, as the basic aspects of the implementation remain unpublished, few studies have taken advantage of the parallelization routines of TNT. In addition, the PVM system is deprecated by many system administrators. One of the most common standards for high performance computing is now MPI (Message Passing Interface). To facilitate the use of the parallel analyses offered by TNT, this paper describes the basic aspects of the implementation, as well as a port of the parallelization interface of TNT into MPI. The use of the new routines is illustrated by reanalysis of seven significant datasets, either recent phylogenomic datasets with many characters (up to 2,509,064 characters) or datasets with large numbers of taxa (up to 13,921 taxa)»

«The specimens of Actinopus Perty, 1833 deposited at the Natural History Museum, London are catalogued. Redescriptions of Actinopus crassipes (Keyserling, 1891), A. harti Pocock, 1895, A. liodon (Ausserer, 1875), A. robustus (O. Pickard-Cambridge, 1892), and A. wallacei F. O. Pickard-Cambridge, 1896 are presented. A lectotype and paralectotypes are designated for A. robustus. Miglio et al. (2020) erroneously considered the type specimens of A. harti and A. liodon to be lost, and further wrongly stated A. liodon would have been deposited in the Naturhistorisches Museum Wien when this was never the case. The type series of A. harti comprises of a holotype female and numerous paratypes. The male of A. harti is described for the first time. Actinopus liodon is represented in the collection by the holotype male and a non-type male, and this species, along with A. pindapoy Miglio, Pérez-Miles & Bonaldo, 2020, is synonymised with A. longipalpis C. L. Koch, 1842 syns nov. The first record of A. longipalpis from Paraguay is reported. The holotype of Actinopus luteipes (Keyserling, 1891) is illustrated, confirmed as an immature female, and is tentatively maintained as a junior synonym of A. crassipes. The male of A. trinotatus Mello-Leitão, 1938 is described for the first time. Conversely, the female of A. tetymapyta Sherwood & Pett, 2022 is described for the first time (on the basis of specimens from the Dr Bohls collection which also contains two adult males). Actinopus vilhena Miglio, Pérez-Miles & Bonaldo, 2020 is recorded from the state of Mato Grosso, Brazil for the first time. An additional female of A. princeps Chamberlin, 1917 from the previously-reported locality Parque Nacional do Itatiaia is illustrated. A new species is proposed on the basis of Bolivian material misidentified as A. wallacei by Miglio et al. (2020), and described in full accordance with Article 13.1.2 of the International Code of Zoological Nomenclature (ICZN, 1999).»

«A new graphical user interface (GUI) for the parsimony program TNT is presented that works under the Linux and Mac operating systems, as well as the Cygwin environment (which runs under Windows). The new interface is based on the GIMP Tool Kit, GTK (version 3). Formerly, only Windows versions of TNT had a GUI. The new interface improves upon the existing Windows GUI in several respects. These changes, together with several additions to the program since the publication of version 1.5, warrant a change in minor version, thus moving from version 1.5 to 1.6. Among the most notable improvements are the possibility to access graphical user dialogs by means of simple commands, to easily save trees in SVG format (“Scalable Vector Graphics”) directly from any tree-diagram being displayed, and to manage analyses in parallel (using multiple processors, by means of the PVM system or “Parallel Virtual Machine”), as well as a generally more stable and consistent behaviour. As the binaries for the new version are compiled as native 64-bit applications, this removes the limitations for accessing large amounts of memory in the previous GUI Windows interface (which is a 32-bit application).»

«The female of Melloina gracilis (Schenkel, 1953), a species previously known only from males, is described. This is the second species of the genus known from both sexes. Detailed morphological description and figures of the female specimen are presented. A reanalysis of Mori & Bertani, 2020 matrix is done and some comments about the familial placement of the genus Melloina Brignoli, 1985 are made. »

«A new mygalomorph spider genus, Afropesa n. gen., is established for three South African species: the type species A. schoutedeni (Benoit, 1965) n. comb., transferred here from Entypesa Simon, 1902, and two newly described congeners, A. gauteng n. sp. and A. schwendingeri n. sp. The new genus differs from other genera of the Entypesidae by a unique set of diagnostic characters, including a flanged embolus and the spermathecae with wide bases and lengthened distal lobes. The three included species can be distinguished from each other by a shape of the male tibia and metatarsus I, as well as by the structure of the embolus and configuration of the spermathecae.»

«Evidence for phylogenetic analysis comes in the form of observed similarities, and trees are selected to minimize the number of similarities that cannot be accounted for by homology (homoplasies). Thus, the classical argument for parsimony directly links homoplasy with explanatory power. When characters are hierarchically related, a first character may represent a primary structure such as tail absence/presence and a secondary (subordinate) character may describe tail colour; this makes tail colour inapplicable when tail is absent. It has been proposed that such character hierarchies should be evaluated on the same logical basis as standard characters, maximizing the number of similarities accounted for by secondary homology, i.e. common ancestry. Previous evaluations of the homology of a given ancestral reconstruction contain the unintuitive quantity “subcharacters” (number of regions of applicability). Rather than counting subcharacters, this paper proposes an equivalent but more intuitive formulation, based on counting the number of changes into each separate state. In this formulation, x-transformations, the homoplasy for the reconstruction is simply the number of changes into the state beyond the first, summed over all states. There is thus no direct connection between homoplasy and number of steps, only between homoplasy and extra steps. The link between the two formulations is that, for any region of applicability of any character, a subcharacter can be interpreted as the change into the state that is plesiomorphic in that region. Although some authors have claimed that the equivalence between maximizing explanatory power and minimizing independent originations of similar features (i.e. the standard justification of parsimony) does not hold for inapplicable characters, evaluating homoplasy with x-transformations clearly connects the two sides of that equation. Furthermore, as the evaluation with x-transformations provides a direct count and a straightforward interpretation of homoplasy, it extends naturally into implied weighting, and sheds light on problems with additive, step-matrix or continuous characters. It also allows deriving transformation costs for recoding hierarchies as step-matrix characters (where recoded states correspond to permissible combinations of states in primary and secondary characters), so that homology of the original observations is properly measured. Those transformation costs set the cost of gaining the primary structure to the maximum difference between “present” states plus cost of loss, and difference between “present” states to the sum of user-defined transformation costs between secondary features. With such recoding, invoking multiple independent derivations of the structure and similar features will cost as many extra “steps” as the instances of similarities (in both original characters) that are not being homologized. The step-matrix recoding also can take into account nested dependences. We present a simple convention for naming characters, which TNT can use to automatically convert the original data into a step-matrix form and set the proper transformation costs. Finally, the basic elements for handling inapplicable characters in the context of maximum-likelihood inference are outlined, and some quantitative comparisons between different approaches to inapplicables are provided.»

«The southern African species of the mygalomorph spider genus Hermacha Simon, 1889, are revised. Eight species are redescribed: H. brevicauda Purcell, 1903; H. caudata Simon, 1889; H. evanescens Purcell, 1903; H. fulva Tucker, 1917; H. lanata Purcell, 1902; H. nigrispinosa Tucker, 1917; H. sericea Purcell, 1902; and H. tuckeri Raven, 1985. The female of H. sericea and the male of H. evanescens are described for the first time. Three new species are described: H. septemtrionalis, sp. nov., H. maraisae, sp. nov., and H. montana, sp. nov. On the basis of their genital morphology H. curvipes Purcell, 1902, and H. nigra Tucker, 1917, are considered incertae sedis. Pionothele capensis Zonstein, 2016, was found to be conspecific with H. brevicauda and is synonymized. The genera Brachytheliscus Pocock, 1902, and Hermachola Hewitt, 1915, are revalidated and redescribed. Hermacha capensis (Ausserer, 1871) and H. crudeni Hewitt, 1913, are transferred to Hermachola. Hermachola crudeni (Hewitt, 1913), originally described from a female, and Hermachola grahami Hewitt, 1915, originally described from a male, were found to be conspecific and synonymized. A new species, Hermachola lyleae, sp. nov., is also described. New morphological characters for the diagnoses of these genera and a dichotomous key for all species considered here are provided. Known distributions are mapped and, where available, ecological data are included. With the exception of H. caudata and H. mazoena Hewitt, 1915, all species are endemic to South Africa, but further survey work in neighboring countries is needed. This work substantially improves the taxonomy of this group of spiders and provides a foundation for further investigation of the diversity and relationships of species within the region.»

«Motivation: TNT (a widely used program for phylogenetic analysis) includes an interpreter for a scripting language, but that implementation is nonstandard and uses several conventions of its own. This article describes the implementation and basic usage of a C interpreter (with all the ISO essentials) now included in TNT. A phylogenetic library includes functions that can be used for manipulating trees and data, as well as other phylogeny-specific tasks. This greatly extends the capabilities of TNT.»

«After more than a century, the genus Lepthercus Purcell, 1902 is revised. Lepthercus dregei Purcell, 1902 and L. rattrayi Hewitt, 1917 are redescribed; with the female of L. dregei described for the first time. Nine new species of Lepthercus are described. A phylogenetic analysis with morphological characters using implied weights and parsimony as optimality criteria, suggests the separation of the genus in two clades. The first clade is formed by L. dippenaarae sp. nov., L. engelbrechti sp. nov., L. haddadi sp. nov., L. rattrayi Hewitt, 1917 and L. sofiae sp. nov., here denominated “Group haddadi”. The species L. confusus sp. nov., Lepthercus dregei Purcell, 1902, Lepthercus filmeri sp. nov., Lepthercus kwazuluensis sp. nov., Lepthercus lawrencei sp. nov. and Lepthercus mandelai sp. nov., form the second clade, here denominated “Group dregei”. The “Group haddadi” is characterized by males with a curved metatarsus I, and a swollen tibia I. The “Group dregei” is supported by the presence of small maxillary cuspules in males. A new diagnosis is provided for Lepthercus as well as an identification key for all species of the genus. New distribution maps for the genus in the country are also presented.»

«Euathlus Ausserer, 1875 is a South American genus of spiders of the family Theraphosidae known from Chile and Argentina. Three new species from Argentina: Euathlus mauryi sp. n. (from San Juan province), Euathlus grismadoi sp. n. (from La Rioja province), and Euathlus pampa sp. n. (from Salta province) are described here. New records of the previous species Euathlus diamante and Euathlus tenebrarum are contributed. The distribution of these new species expands the geographical distribution of the genus along the Andean hills, with Salta province as the northernmost record of the genus. A key is provided for identification of Euathlus species as well as a map with all the records in Argentina»

«A new species of Farlowella is described from the Bermejo River basin, in Salta and Jujuy provinces, northwestern Argentina. The new species belongs to the Farlowella nattereri species group. The new species is diagnosed by the following combination of characters: marbled rostrum, five rows of lateral plates series, relatively short snout (snoutmouth length less than 50.0% of head length), complete half-moon shaped spot on caudal fin, and short predorsal distance (37.8-41.8% of standard length).»

«Gymnogeophagus jaryi, new species, is described from Southern tributaries of the Middle Paraná basin in Misiones. It can be distinguished from all other members of the genus, except from G. australis and G. caaguazuensis, by the presence of a hyaline to grey anterior portion of the dorsal fin. Gymnogeophagus jaryi differs from G. caaguazuensis by a longer caudal peduncle, caudal fin not lyrate, central portion of scales on dorsal portion of trunk light iridescent blue and by white spots in soft portion of dorsal fin in adult males, and from G. australis by the light iridescent blue coloration of central portion of scales on the dorsal portion of trunk and tail, and by the lack of scales on the soft portion of the dorsal fin. Additionally, it can be diagnosed by the following unique combination of characters: 10–11 dorsal-fin branched rays, 27–30 E1 scales, absence of lips thickening, and, in males, by the possession of a hump in adults, caudal fin not lyrate, presence of large white spots forming transversal stripes distally and in anterior area of the dorsal fin’s soft portion, central area of scales on the dorsal portion of the trunk light iridescent blue, lack of scales on the base of the dorsal fin’s soft portion, absence of a conspicuous and oblique dark band from the eye to the anterior border of the head, anterior portion of dorsal fin hyaline to grey, scales of the midlateral spot each bearing a semicircular light blue blotch, head hump starting at the horizontal through the eyes, concave anterior profile in lateral view, base of unpaired fins yellow, and whitish hyaline spots on caudal fin. The new species, based on mtDNA phylogeny, is the sister species of G. caaguazuensis from the Paraguay basin and is closely related to G. australis.»

«Actinopus specimens from different localities in Uruguay that did not match any of the previously species present in the country were examined, and four new species are described: A. coboi sp. nov., from Colonia province; A. fernandezi sp. nov., from Salto province; A. simoi sp. nov., from Maldonado province; and A. uruguayense sp. nov., from Colonia and Cerro Largo provinces. The record of the species A. longipalpis for Montevideo is rejected and A. liodon is considered “species inquirenda”. Actinopus coboi has spermathecae with an apical lobe diagonally directed; A. fernandezi is characterized by a stylized copulatory bulb and its greater number of retrolateral thorns on tibia II. Actinopus simoi can be distinguished from A. uruguayense by its carapace with a dark coloration; a reddish coloration in the palpal tibia and the shape of its spermathecae and copulatory bulb. With the presence of the Argentinian species—A. gerschiapelliarum, A. puelche and A. insignis—the number of species known in the country is increased to nine. All new species are diagnosed and illustrated; a dichotomous key to all species of Actinopus from Uruguay is also provided »

«The spider family Migidae Simon, 1889 is represented in Chile by three genera: Calathotarsus Simon, 1903, Mallecomigas Goloboff & Platnick, 1987 and Goloboffia Griswold & Ledford, 2001. In the present study, four new species of Goloboffia from Chile are described, increasing the known diversity and geographic distribution of the genus. Goloboffia megadeth sp. nov. and G. pachelbeli sp. nov., are described based on males and females; Goloboffia griswoldi sp. nov. and G. biberi sp. nov. are known only by females.»

«Allometry constitutes an important source of morphological variation. However, its influence in head development in anurans has been poorly explored. By using geometric morphometrics followed by statistical and comparative methods we analyzed patterns of allometric change during cranial postmetamorphic ontogeny in species of Nest?building frogs Leptodactylus (Leptodactylidae). We found that the anuran skull is not a static structure, and allometry plays an important role in defining its shape in this group. Similar to other groups with biphasic life?cycle, and following a general trend in vertebrates, ontogenetic changes mostly involve rearrangement in rostral, otoccipital, and suspensorium regions. Ontogenetic transformations are paralleled by shape changes associated with evolutionary change in size, such that the skulls of species of different intrageneric groups are scaled to each other, and small and large species show patterns of paedomorphic/peramorphic features, respectively. Allometric trajectories producing those phenotypes are highly evolvable though, with shape change direction and magnitude varying widely among clades, and irrespective of changes in absolute body size. These results reinforce the importance of large?scale comparisons of growth patterns to understand the plasticity, evolution, and polarity of morphological changes in different clades.»

«Austrolebias wichi, new species, is herein described from seasonal ponds of the Bermejo river basin in the Western Chacoan district in northwestern Argentina. This species was found in a single pond, a paleochannel of the Bermejo River, which is seriously disturbed by soybean plantations surrounding it. Despite intensive sampling in the area, this species was only registered in this pond where it was relatively scarce. Therefore, we consider this species as critically endangered. This species is the sister species of A. patriciae in our phylogenetic analyses and is similar, in a general external aspect, to A. varzeae and A. carvalhoi. It can be distinguished among the species of Austrolebias by its unique color pattern in males. Additionally, from A. varzeae by presenting a supraorbital band equal or longer than the infraorbital band (vs. shorter) and from A. patriciae by the convex dorsal profile of head (vs. concave). Further diagnostic characters and additional comments on its ecology and reproduction are provided.»

«Bird pollination is relatively common in the tropics, and especially in the Americas. In the predominantly Neotropical tribe Myrteae (Myrtaceae), species of two genera, Acca and Myrrhinium, offer fleshy, sugary petals to the consumption of birds that otherwise eat fruits, thus pollinating the plants in an unusual plant-animal interaction. The phylogenetic position of these genera has been problematic, and therefore, so was the understanding of the evolution of this interaction. Here we include new sequences of Myrrhinium atropurpureum in a comprehensive molecular phylogeny based on a balanced sample of two plastid and two nuclear markers, with the aim of providing the historical framework of pollination by frugivorous birds in Myrteae. We developed 13 flower and inflorescence characters that comprehensively depict the macroscopic morphological components of this interaction. Bayesian and parsimony phylogenies concur in placing both Acca and Myrrhinium in a clade with Psidium species; with Myrrhinium sister to Psidium. Mapping of morphological characters indicated some degree of convergence (e.g., fleshy petals, purplish display) but also considerable divergence in key characters that point to rather opposing pollination strategies and also different degrees of specialization in Acca versus Myrrhinium. Pollination by frugivorous birds represents a special case of mutualism that highlights the evolutionary complexities of plant-animal interactions.»

«The genus Actinopus Perty, 1833, is revised for Argentina, comprising a total of 23 species. The female of A. insignis (Holmberg, 1881) is described for the first time; the species is found in northern Buenos Aires, southern Santa Fe, and Uruguay. The female of A. longipalpis (Koch, 1842), previously known only from the male type from Uruguay, is described for the first time, and the species is newly cited for Argentina (Entre Ríos). Twenty new species are recognized, described and illustrated. Thirteen of the new species are based on males and females (A. reycali, sp. nov., from Jujuy and Salta; A. clavero, sp. nov., from Córdoba; A. szumikae, sp. nov., from Córdoba, southern Buenos Aires, Santa Fe and Corrientes; A. coylei, sp. nov., from Salta and Santiago del Estero, A. argenteus, sp. nov., from Santiago del Estero, Córdoba and Catamarca, A. ramirezi, sp. nov., from Misiones, A. patagonia, sp. nov., from Chubut, La Pampa, Río Negro and southern Buenos Aires, A. gerschiapelliarum, sp. nov., from Córdoba, northern Buenos Aires, southern Santa Fe, northern La Pampa and Canelones in Uruguay, A. pampa, sp. nov., from La Pampa, A. septemtrionalis, sp. nov., from Salta, Tucumán, Catamarca, and Formosa, A. taragui, sp. nov., from Corrientes, Chaco, and Misiones, A. excavatus, sp. nov., from Córdoba, A. casuhati, sp. nov., from southern Buenos Aires). Only one of the new species described is based on females only (A. indiamuerta, sp. nov., from Tucumán); and the remaining six on males (A. puelche, sp. nov., from southern Buenos Aires and Uruguay, A. cordobensis, sp. nov., from San Luis and Córdoba, A. magnus, sp. nov., from Córdoba, A. ariasi, sp. nov., from Formosa, A. palmar, sp. nov., from Entre Ríos, and A. balcarce, sp. nov., from southern Buenos Aires). New morphological characters that can help solve phylogenetic relationships within the genus are described. A dichotomous key for all the species from Argentina is provided, as well as maps of the known geographic distribution for all the species. Three of the species treated here (A. gerschiapelliarum, A. puelche, and A. insignis) are recorded also for Uruguay. »

«New specimens of the genus Hapalotremus (Theraphosinae) are revised based on the examination of types and additional material collected in Argentina, Bolivia and Peru. A new generic diagnosis is proposed. New information and illustrations are provided for known species and seven new species were recognized and are newly described and illustrated. Hence, Hapalotremus comprises 10 valid species, distributed along the Andes and Yungas in western South America. All species are keyed and mapped. New taxonomic features are included in the descriptions and the detail of embolus keels morphology and positions are described for the first time for the genus. Information on species habitat is included. The highest altitude record for a Theraphosidae spider, living at 4524 m above sea level, is reported.»

«One of the lasting controversies in phylogenetic inference is the degree to which specific evolutionary models should influence the choice of methods. Model-based approaches to phylogenetic inference (likelihood, Bayesian) are defended on the premise that without explicit statistical models there is no science, and parsimony is defended on the grounds that it provides the best rationalization of the data, while refraining from assigning specific probabilities to trees or character-state reconstructions. Authors who favour model-based approaches often focus on the statistical properties of the methods and models themselves, but this is of only limited use in deciding the best method for phylogenetic inference—such decision also requires considering the conditions of evolution that prevail in nature. Another approach is to compare the performance of parsimony and model-based methods in simulations, which traditionally have been used to defend the use of models of evolution for DNA sequences. Some recent papers, however, have promoted the use of model-based approaches to phylogenetic inference for discrete morphological data as well. These papers simulated data under models already known to be unfavourable to parsimony, and modelled morphological evolution as if it evolved just like DNA, with probabilities of change for all characters changing in concert along tree branches. The present paper discusses these issues, showing that under reasonable and less restrictive models of evolution for discrete characters, equally weighted parsimony performs as well or better than model-based methods, and that parsimony under implied weights clearly outperforms all other methods. »

«Cetopsorhamdia iheringi (Siluriformes, Heptapteridae): a new record for the freshwater ichthyofauna of Argentina»

«A new genus of the subfamily Euagrinae is described from Chile, Vilchura calderoni gen. et sp. nov. this is the second euagrine genus described for South America. The genus is distinguished from other euagrine genera by its short and recurved fovea, the presence of a megaspine on both male tibiae I and II, and the female spermathecae divided into 2–3 lobes.»

«A new species of Astyanax is described from the arheic system of Río Sucuma, in Catamarca, northwestern Argentina. The new species is distinguished from its congeners by a combination of characters including the presence of a broad vertical humeral spot, absence of maxillary teeth, and absence of circuli in posterior field of scales. Furthermore, this species is distinguished by the orbital diameter, head length, branched anal-fin rays, perforated lateral-line scales, transverse scales, dentary teeth with abrupt decrease in size. This species is, to date, the single known fish endemic of Río Sucuma basin.»

«In this paper we describe Heptapterus mandimbusu sp. n., a new species of heptapterid catfish from a small tributary of the Uruguay River Basin in Misiones-Argentina. This new species is distinguished from all other congeners by the unique coloration pattern with aggregated melanophores scattered on dorsal and lateral surface of body, forming conspicuous size-variable blotches, and the combination of a long interdorsal distance (13.8–18.9 % SL), 14–18 anal-fin rays, short maxillary barbels (52.2–74.5 % HL), and the adipose fin confluent with caudal fin.»

«Aim: To develop and implement a method for phylogenetic biogeography that is both event based and geographically explicit, that is, that uses the geographical ranges observed in the terminals instead of ‘predefined areas.’ Methods: The method, GEM (Geographically explicit Event Model), attributes vicariance, sympatry (range copying), point sympatry (subset sympatry) or founder events, to the internal nodes of the tree. The cost of a reconstruction is calculated as the event cost plus the amount of range changes along a branch, and the best reconstruction is the combination of the event and range assignments that minimize the cost. Results: The approach was implemented in a computer program, evs, using a geographical data model (a raster) in which range changes were measured by pixel counts. The program can be used in real-sized datasets, using an heuristic to find reasonable solutions in short times. Main conclusion: GEM provides a method for direct analysis of joint data on phylogeny and explicit distribution ranges, and proposes both the ancestral ranges and the biogeographical events connected with cladogenesis.»

«Identification of Andean bear (Tremarctos ornatus) specimens is essential for obtaining demographic estimates of their populations. Camera traps are a noninvasive tool that allows such identification. The efficiency of using photographic or video records for identifying specimens of this species in a wild population in Colombia was compared. A total of 18 camera traps were operated from November 2011 through November 2013; each sample station included a single camera at 0.6 m height, with a bait placed 2 m in front of it at 1.5 m height. Four key external morphological features were chosen for identifying the specimens: presence, shape and colour of facial; presence, shape and colour of pectoral markings; estimated body size; and sex. For each recording event, a visual file (photograph or video) was scored as “good” if it showed at least three key identification features, thus allowing the correct identification of the specimen; or as “bad” ïf it showed fewer than three features, making identification impossible. Successful recording events were those that included at least one good visual file (photograph or video). A total of 4,588 visual files were obtained: 4,324 photographs in 325 recording events and 264 videos in 260 recording events. 5.25% of the photographs and 53.03% of the videos were scored as good files. 26.77% of the photograph-based and 49.62% of the video-based recording events were successful. There were statistically significant differences between the percentage of good photographs and good videos obtained every time a camera trap was activated in the presence of a bear (Mann-Whitney, P = 1.37E-11). The low percentage of successful recording events obtained with photographs (26.77%) compared to that obtained with videos (50.38%), is consistent with results previously reported for this same species in Ecuador using photographs (25%). The higher percentage of good videos (53.03%) compared to that of good photographs (5.25%), is consistent with the statistically significant difference found between the percentage of good photos and good videos obtained every time a camera trap was activated in the presence of a bear (Mann-Whitney, P = 1.37E-11), and with results previously reported for the Asian black bear (Ursus thibetanus, 70%) using sample stations including a single camera trap with video format. The use of video for recording Andean bear specimens allows the observation of individuals from different viewpoints and distances, even with the use of sample stations including a single camera trap, thus minimizing the effect of light reflection on the recognition of key identification features. Additionally, the video format allowed recognition of particular physical conditions, such as limp or rigid limbs in some specimens, which cannot be recognized in photographs. In this study case, information obtained with video records provides a greater ability to recognize individual marks in the specimens and to identify them.»

«This paper describes two types of problems related to tree shapes, as well as algorithms that can be used to solve these problems. The first problem is that of comparing the similarity of the unlabelled shapes instead of merely their degree of balance, in a manner analogous to that routinely used to compare topologies for labelled trees. There are possible practical applications for this comparison, such as determining, based on tree shape similarity alone, whether the taxa in two phylogenies are likely to have a correspondence (e.g. hosts and parasites with high specificity). It is shown that tree balance is insufficient for this task and that standard measures of topological difference (Robinson-Foulds distances, SPR distances or retention indices of the matrices representing the trees, MRPs) can be easily adapted to the problem. The second type of problem is to determine whether taxa of uncertain matching unique to two different phylogenies could correspond to each other (e.g. the same species in larvae and adults of metamorphic animals, fossils known from different body parts). This second problem can be solved by either relabelling taxa in such a way that the number of consensus nodes is maximized, or relabelling taxa in such a way that the sum of the number of steps in the MRP of each tree mapped onto the other is minimum.»

«Caviomorph rodents are one of the most diverse mammalian groups in the Neotropics; they display astonishing eco-morphological variation, including unparalleled size range. Here we analyse evolutionary patterns among extant caviomorphs, particularly their rates of diversification and size evolution. The results show large heterogeneity in the evolutionary dynamics of caviomorphs. Three clear episodes of rapid increase of the diversification rate were detected; two of them during the Oligocene were related to the diversification of major clades; a third one, in the late Miocene, was related to the diversification of the genus Ctenomys. Regarding size, relatively low rates characterized much of Octodontoidea, the most speciose among the main caviomorph clades. Other clades, especially Cavioidea and Chinchilloidea, showed much accelerated evolutionary rates and the highest number of size changes, particularly increases; furthermore, they include extinct representatives that reached very large to gigantic size. Thus, although the macroevolutionary dynamics of caviomorphs were complex and heterogeneous in our study, the pathways followed by different clades seem to display their own particular characteristics. This should be analysed in greater depth through new, greater scale analyses incorporating the rich fossil record of caviomorphs, which contributes essential information to understand the evolution of these peculiar rodents.»

«En este capítulo abordamos la importancia de los estudios de morfología comparada en diferentes estadios del desarrollo ontogenético de los anfibios anuros, enfatizando en etapas no adultas. En primer lugar ejemplificamos estudios estáticos de variación estructural en embriones y larvas, con hincapié en la morfología de estructuras embrionarias transitorias y en características típicamente larvales. Seguidamente, consideramos métodos y ejemplos de estudios dinámicos, donde las trayectorias completas de cambio son comparadas interespecíficamente. En este contexto, incluimos cambios de forma respecto del incremento de tamaño durante la ontogenia (alometría), y cambios de forma y/o tamaño respecto del tiempo de desarrollo (heterocronía de crecimiento). Adicionalmente, como alternativa operativa que no considera el tiempo como variable, resumimos el marco teórico y ejemplos en estudios de heterocronía de secuencias.»

«Aim. Understanding patterns of endemism is a key to deciphering the history of biotas and setting conservation priorities, but resolving the complexity of distributional patterns quantitatively into areas of endemism is often a difficult task. We report here an analysis of a comprehensive biodiversity dataset for the study of endemism, including virtually all vouchered records available for resident land birds of Mexico (> 100,000 georeferenced data points for all 780 species). Location. Mexico. Methods. The dataset was analysed with methods that recover areas without assuming prior endemic status for any species. This grid-based method for detecting areas of endemism considers co-occurrence and exclusiveness of species in alternative sets of geographic cells at different spatial resolutions, and finds optimal sets using heuristic, computationally intensive searches. Results. We provide the most detailed study of endemism in Mexico to date. Our analysis recovered 17 of 18 previously recognized areas of endemism for Mexican birds, plus many additional areas clearly supported by distributional data totalling 33 areas of endemism at different spatial scales. These areas cover 70% of the country’s surface and form a network of nested and partially overlapping regions, some of which are also disjoint. Main conclusions. This picture contrasts strongly with previous conceptions of areas of endemism as non-overlapping and spatially simple in terms of scale. Our results reveal that endemism may be spatially complex and shed new light on its role as a key manifestation of biodiversity. Species identified as endemic to these areas comprise > 30% of the land birds of Mexico, with a disproportionately large fraction endangered according to IUCN or SEMARNAT.»

«The hindlimbs in bats are functionally adapted to serve as a hook to attach to the mother from birth, and to roost during independent life. Although bats exhibit different terrestrial locomotion capabilities involving hindlimbs, hindlimb morphology and postnatal development have been poorly studied. We describe in detail the postnatal development and bone morphology of hindlimbs of the nimble walker vampire bat, Desmodus rotundus, and compare adult characters with the insectivorous Molossus molossus (erratic walker) and the frugivorous Artibeus lituratus (non-walker). The advanced ossification of most hindlimb elements of D. rotundus at the newborn stage is consistent with the functional role of this structure at birth in bats. The development completion events of hindlimb bone elements and bone processes in D. rotundus coincide with the cranial bone processes completion and suture closure events. Those events occur when individuals begin to feed by themselves. There are differences in the number and position of bone processes and sesamoids in adults among the compared species, most of which are described for the first time, and in the case of D. rotundus and M. molossus mostly related to a greater and tight articulation between elements. These facts seem to be closely associated with the different terrestrial locomotion capabilities, and in the case of the exclusively sanguivorous D. rotundus with specializations for obtaining food.»

«The Liolaemid genus Phymaturus is a clade of saxicolous lizards with 44 species recognized, grouped in the Phymaturus palluma and the Phymaturus patagonicus groups. The chromosome data about this genus are extremely scarce; however, unpublished evidence suggests a great karyotypic diversity, mainly in the P. palluma group. In this work, we describe the karyotypes of six species of the P. palluma group (one of them unnamed) and report a multiple chromosome sex determination system with heterogametic males (X?X?X?X? /X?X?Y). This sex-system represents a putative synapomorphy for the group. In accordance with the published literature and data obtained in this study, we report a wide variability for the diploid number of the P. palluma group (2N = 26 to 36) but same autosomic fundamental number in all the species of the clade (FNa = 32). Such variation is a consequence of different numbers of telocentric macroautosome pairs among karyotypes (2 to 10), suggesting chromosomal evolution of the group, driven mainly by successive Robertsonian rearrangements.»

«The cranium, postcranium, and osteological variation of Physalaemus nattereri (Steindachner) are described. The main sources of variation involve the degree of mineralization of the nasal capsule and the lengths of dermal skull bones (e.g., vomer, sphenethmoid, and neopalatine). Osteologically, P. nattereri differs from its congeners by the anterior placement of the jaw articulation (which lies anterior to the intersection between the alae and cultriform process of parasphenoid), and by the separation of the frontoparietals from the anterior margins of exoccipitals. Descriptions of the nasal capsule, the auditory apparatus, and the iliosacral articulation are presented for the first time for this species. One putative morphological synapomorphy is presented for the P. signifer clade.»

«The cranium, postcranium, and osteological variation of Physalaemus nattereri (Steindachner) are described. The main sources of variation involve the degree of mineralization of the nasal capsule and the lengths of dermal skull bones (e.g., vomer, sphenethmoid, and neopalatine). Osteologically, P. nattereri differs from its congeners by the anterior placement of the jaw articulation (which lies anterior to the intersection between the alae and cultriform process of parasphenoid), and by the separation of the frontoparietals from the anterior margins of exoccipitals. Descriptions of the nasal capsule, the auditory apparatus, and the iliosacral articulation are presented for the first time for this species. One putative morphological synapomorphy is presented for the P. signifer clade.»

«The inference of phylogenetic hypotheses from landmark data has been questioned during the last two decades. Besides theoretical concerns, one of the limitations pointed out for the use of landmark data in phylogenetics is its (supposed) lack of information relevant to the inference of phylogenetic relationships. However, empirical analyses are scarce; there exists no previous study that systematically evaluates the phylogenetic performance of landmark data in a series of data sets. In the present study, we analysed 41 published data sets in order to assess the correspondence between the phylogenetic trees derived from landmark data and those obtained with alternative and independent sources of evidence, and determined the main factors that might affect this inference. The data sets presented a variable number of terminals (5–200) and configurations (1–14), belonging to different taxonomic groups. The results showed that for most of the data sets analysed, the trees derived from landmark data presented a low correspondence with the reference phylogenies. The results were similar irrespective of the phylogenetic method considered. Complementary analyses strongly suggested that the limited amount of evidence included in each data set (one or a few landmark configurations) is the main cause for that low correspondence: the phylogenetic analysis of eight data sets that presented three or more configurations clearly showed that the inclusion of several landmark configurations improves the results. In addition, the analyses indicated that the inclusion of landmark data from different configurations is more important than the inclusion of more landmarks from the same configuration. Based on the results presented here, we consider that the poor results previously obtained in phylogenetic analyses based on landmark data were not caused by methodological limitations, but rather due to the limited amount of evidence included in the data sets.»

«A detailed re-description of the type specimen of Trichopelma cubanum (Simon, 1903) is presented. Comments and observations are made regarding morphological characters, such as the absence of teeth on the paired claws and the presence of small teeth on the anterior edge of the booklung opening. These characters, found in other species of Trichopelma Simon, 1888 (represented in the Neotropical region by 16 species), suggest that the recent transfer of the genus to Theraphosidae may be unjustified, and that Trichopelma may indeed be more closely related to the Barychelidae.»

«Redescription of Snellenius atratus and S. peruensis (Braconidae: Microgastrinae), and Distribution of the Genus in South America. Redescriptions of S. atratus Shenefelt y S. peruensis Shenefelt, cited for Peru, with the contribution of new characters and illustrations, as well as data on intra-specific variation for its better identification. The male genitalia are described for the first time of all South American species. Distribution maps of the four South American species described by Shenefelt 1968 (S. atratus, S. peruensis, S. bicolor and S. tricolor) are shown. New locations for Peru of these two first species and S. bicolor for Argentina are recorded.»

«Tendons are directly associated with movement, amplifying power and reducing muscular work. Taking into account habitat and locomotor challenges faced by anurans, we identify the more conspicuous superficial tendons of a neotropical anuran group and investigate their relation to the former factors. We show that tendons can be visualized as an anatomical framework connected through muscles and/or fascia, and describe the most superficial tendinous layer of the postcranium of Leptodactylus latinasus. To analyze the relation between tendon morphology and ecological characters, we test the relative length ratio of 10 tendon–muscle (t-m) elements in 45 leptodactylid species while taking phylogeny into account. We identify the evolutionary model that best explains our variables. Additionally, we optimize t-m ratio values, and the shape of the longissimus dorsi insertion onto a selected phylogeny of the species. Our data show the existence of an all-purpose morphology that seems to have evolved independently of ecology and functional requirements. This is indicated by no significant relation between morphometric data of the analyzed tendons and habitat use or locomotion, a strong phylogenetic component to most of the analyzed variables, and a generalized pattern of intermediate values for ancestral states. Ornstein-Uhlenbeck is the model that best explains most t-m variables, indicating that stabilizing selection or selective optima might be driving shifts in tendon length within Leptodactylidae. Herein, we show the substantial influence that phylogeny has on tendon morphology, demonstrating that a generalized and stable morphological configuration of tendons is adequate to enable versatile locomotor mode and habitat use. This is an attempt to present the tendinous system as a framework to body support in vertebrates, and can be considered a starting point for further ecomorphological research of this anatomical system in anurans.»

«1. In visually driven seed dispersal mutualisms, natural selection should promote plant strategies that maximize fruit visibility to dispersers. Plants might increase seed dispersal profitability by increasing conspicuousness of fruit display, understood as a plant strategy to maximize fruit detectability by seed dispersers. 2. The role of different plant traits in fruit choice and consumption by seed dispersers has been broadly studied. However, there is no clear evidence about the importance of the traits that increase conspicuousness of fruit display. Because strategies to maximize conspicuousness of fruit display are diverse, and usually are expected to be costly, we would expect that individual plant species will produce an efficient combination of traits. 3. We explored this prediction with 62 fleshy fruited plant species of a subtropical Andean forest (Southern Yungas), and using a large dataset of fruit consumption by birds (4476 records). Conspicuousness of fruit display was characterized by both fruit and plant traits including chromatic contrast, size, exposure, aggregation and crop size of fruits. We also considered phylogenetic effects on phenotypic variation. 4. Fruit consumption was explained by fruit chromatic contrast depending on fruit crop size. These traits revealed low phylogenetic effects, with the exception of four plant clades at different levels in the phylogenetic tree. Negative correlations between pairs of traits support our assumption that fruit display traits are costly, suggesting natural selection favours parsimonious evolutionary pathways. 5. Plant species seem to rely on conspicuousness of fruit display by a combination of traits that might minimize costs of fruit display. This appears adaptively relevant to improve communication with mutualistic animals, to increase fruit consumption in a community context and, ultimately, to enhance the profitability of seed dispersal.»

«The Panthera lineage is a monophyletic clade of felids, supported by both morphological and molecular evidence. The lineage includes large species with cranial similarity such as Panthera leo and P. tigris, and other with very different cranium such as P. pardus. The aim of our work was to study the cranial ontogeny of Pantherines, elucidating whether their cranial shape is a product of size or phylogeny, and to compare these findings with available information about other carnivores. We studied 370 specimens using geometric morphometrics technique in three dimensions. Panthera leo and P. tigris show similar ontogenetic trajectories, sharing adult crania with wider rostrum, shorter basicranium and vertical occipital plate. The cranial configuration of P. leo is a scaling version of P. tigris. P. pardus shows the most different cranial pattern, with adults having a rounded braincase and zygomatic arches less expanded than the rest, whereas P. onca occupies an intermediate place between these patterns. P. pardus is the species with the smallest birth weight and the lowest growth rate, reaching a final size and shape later than the remaining species. Adult shape morphology reflects no relation to phylogenetic placement of the species and it is probably related to Pantherine body size. »

«En la presente contribución se detalla el registro de fósiles vertebrados mesozoicos en el noroeste de Argentina. El mismo se compone de una parte Triásica y otra Cretácica, pero hay también un registro puntual del Jurásico. El Triásico se presenta en la cuenca de Ischigualasto-Villa Unión en las provincias de San Juan y La Rioja y en la cuenca de Marayes-El Carrizal al sur de San Juan, mientras que el Jurásico Inferior existe en la última cuenca y en la Formación Cañón del Colorado en el centro de la provincia de San Juan. El Cretácico está documentado en la Formación Los Llanos de La Rioja y en la cuenca del Noroeste en Jujuy y Salta. El Triásico Superior es el mejor representado mostrando una buena diversidad de arcosauromorfos. El mejor registro de dinosauriformes no dinosaurianos es en la Formación Chañares, mientras que los dinosaurios más antiguos del mundo aparecen ya bien diversificados en la Formación Ischigualasto y se vuelven abundantes en Los Colorados. Dicinodontes son componentes residuales (poco diversos y abundantes), mientras que los cinodontes son abundantes en la Formación Chañares y abundantes y más diversificados en la fauna de Ischigualasto. Registros antiguos de tortugas existen en las formaciones Los Colorados y Quebrada del Barro, y en esta última hay también esfenodontes. En el Cretácico de la Formación Los Llanos se documentaron nidadas de huevos de saurópodos y restos fragmentarios de cocodrilos. En la cuenca del Noroeste, la Formación Las Curtiembres registra peces teleósteos, ranas pípidas, tortugas pleurodiras, mesoeucrocodilidos, dinosaurios terópodos y enantiornites; mientras que en la Formación Los Blanquitos fueron hallados dinosaurios titanosaúridos y terópodos y un diente de cocodrilo. La Formación Lecho está dominada por dinosaurios titanosaurios y también se hallaron terópodos y enantiornites. Finalmente en la Formación Yacoraite hay peces y cocodrilos, así como también huellas atribuidas a diferentes grupos de dinosaurios. ABSTRACT Mesozoic fossil vertebrates from northwestern Argentina. We are presenting a synthesis of the vertebrate fossil record from northwestern Argentina. The Triassic is represented in the Ischigualasto-Villa Unión Basin in La Rioja and San Juan provinces and in the Marayes-El Carrizal Basin in the south of San Juan, whereas the Lower Jurassic crops out in the latter basin and in the Cañón del Colorado Formation in the center of San Juan Province. Cretaceous fossils are documented in the Los Llanos Formation in La Rioja Province and in the Noroeste Basin in Jujuy and Salta provinces. The Upper Triassic is best represented in the Ischigualasto-Villa Union Basin, featuring well-diversified archosauromorphs. Non dinosaur dinosauriforms are well diversified in the Chañares Formation, and the world’s oldest dinosaurs are already well diversified in the Ischigualasto Formation and become abundant in Los Colorados. Ancient records of terrestrial turtles exist in the Los Colorados and Quebrada del Barro formations. Sphenodontians are also represented in the latter unit. A nesting site of sauropods and fossils of a crocodile are documented in the Cretaceous Los Llanos Formation. In the Noroeste Basin, the Las Curtiembres Formation has records of teleost fish, pipid frogs, pleurodire turtles, mesoeucrocodiles, theropod dinosaurs and enantiornithes birds; whereas in the Los Blanquitos Formation were found titanosaurid and theropod dinosaurs, as well as a crocodile tooth. The Lecho Formation is dominated by titanosaurid dinosaurs and also record theropod dinosaurs and enantiornithes. Finally, in the Yacoraite Formation there are fish and crocodiles, as well as tracks attributed to different groups of dinosaurs.»

«We present a phylogenetic analysis of spiders using a dataset of 932 spider species, representing 115 families (only the family Synaphridae is unrepresented), 700 known genera, and additional representatives of 26 unidentified or undescribed genera. Eleven genera of the orders Amblypygi, Palpigradi, Schizomida and Uropygi are included as outgroups. The dataset includes six markers from the mitochondrial (12S, 16S, COI) and nuclear (histone H3, 18S, 28S) genomes, and was analysed by multiple methods, including constrained analyses using a highly supported backbone tree from transcriptomic data. We recover most of the higher-level structure of the spider tree with good support, including Mesothelae, Opisthothelae, Mygalomorphae and Araneomorphae. Several of our analyses recover Hypochilidae and Filistatidae as sister groups, as suggested by previous transcriptomic analyses. The Synspermiata are robustly supported, and the families Trogloraptoridae and Caponiidae are found as sister to the Dysderoidea. Our results support the Lost Tracheae clade, including Pholcidae, Tetrablemmidae, Diguetidae, Plectreuridae and the family Pacullidae (restored status) separate from Tetrablemmidae. The Scytodoidea include Ochyroceratidae along with Sicariidae, Scytodidae, Drymusidae and Periegopidae; our results are inconclusive about the separation of these last two families. We did not recover monophyletic Austrochiloidea and Leptonetidae, but our data suggest that both groups are more closely related to the Cylindrical Gland Spigot clade rather than to Synspermiata. Palpimanoidea is not recovered by our analyses, but also not strongly contradicted. We find support for Entelegynae and Oecobioidea (Oecobiidae plus Hersiliidae), and ambiguous placement of cribellate orb-weavers, compatible with their non-monophyly. Nicodamoidea (Nicodamidae plus Megadictynidae) and Araneoidea composition and relationships are consistent with recent analyses. We did not obtain resolution for the titanoecoids (Titanoecidae and Phyxelididae), but the Retrolateral Tibial Apophysis clade is well supported. Penestomidae, and probably Homalonychidae, are part of Zodarioidea, although the latter family was set apart by recent transcriptomic analyses. Our data support a large group that we call the marronoid clade (including the families Amaurobiidae, Desidae, Dictynidae, Hahniidae, Stiphidiidae, Agelenidae and Toxopidae). The circumscription of most marronoid families is redefined here. Amaurobiidae include the Amaurobiinae and provisionally Macrobuninae. We transfer Malenellinae (Malenella, from Anyphaenidae), Chummidae (Chumma) (new syn.) and Tasmarubriinae (Tasmarubrius, Tasmabrochus and Teeatta, from Amphinectidae) to Macrobuninae. Cybaeidae are redefined to include Calymmaria, Cryphoeca, Ethobuella and Willisius (transferred from Hahniidae), and Blabomma and Yorima (transferred from Dictynidae). Cycloctenidae are redefined to include Orepukia (transferred from Agelenidae) and Pakeha and Paravoca (transferred from Amaurobiidae). Desidae are redefined to include five subfamilies: Amphinectinae, with Amphinecta, Mamoea, Maniho, Paramamoea and Rangitata (transferred from Amphinectidae); Ischaleinae, with Bakala and Manjala (transferred from Amaurobiidae) and Ischalea (transferred from Stiphidiidae); Metaltellinae, with Austmusia, Buyina, Calacadia, Cunnawarra, Jalkaraburra, Keera, Magua, Metaltella, Penaoola and Quemusia; Porteriinae (new rank), with Baiami, Cambridgea, Corasoides and Nanocambridgea (transferred from Stiphidiidae); and Desinae, with Desis, and provisionally Poaka (transferred from Amaurobiidae) and Barahna (transferred from Stiphidiidae). Argyroneta is transferred from Cybaeidae to Dictynidae. Cicurina is transferred from Dictynidae to Hahniidae. The genera Neoramia (from Agelenidae) and Aorangia, Marplesia and Neolana (from Amphinectidae) are transferred to Stiphidiidae. The family Toxopidae (restored status) includes two subfamilies: Myroinae, with Gasparia, Gohia, Hulua, Neomyro, Myro, Ommatauxesis and Otagoa (transferred from Desidae); and Toxopinae, with Midgee and Jamara, formerly Midgeeinae, new syn. (transferred from Amaurobiidae) and Hapona, Laestrygones, Lamina, Toxops and Toxopsoides (transferred from Desidae). We obtain a monophyletic Oval Calamistrum clade and Dionycha; Sparassidae, however, are not dionychans, but probably the sister group of those two clades. The composition of the Oval Calamistrum clade is confirmed (including Zoropsidae, Udubidae, Ctenidae, Oxyopidae, Senoculidae, Pisauridae, Trechaleidae, Lycosidae, Psechridae and Thomisidae), affirming previous findings on the uncertain relationships of the “ctenids” Ancylometes and Cupiennius, although a core group of Ctenidae are well supported. Our data were ambiguous as to the monophyly of Oxyopidae. In Dionycha, we found a first split of core Prodidomidae, excluding the Australian Molycriinae, which fall distantly from core prodidomids, among gnaphosoids. The rest of the dionychans form two main groups, Dionycha part A and part B. The former includes much of the Oblique Median Tapetum clade (Trochanteriidae, Gnaphosidae, Gallieniellidae, Phrurolithidae, Trachelidae, Gnaphosidae, Ammoxenidae, Lamponidae and the Molycriinae), and also Anyphaenidae and Clubionidae. Orthobula is transferred from Phrurolithidae to Trachelidae. Our data did not allow for complete resolution for the gnaphosoid families. Dionycha part B includes the families Salticidae, Eutichuridae, Miturgidae, Philodromidae, Viridasiidae, Selenopidae, Corinnidae and Xenoctenidae (new fam., including Xenoctenus, Paravulsor and Odo, transferred from Miturgidae, as well as Incasoctenus from Ctenidae). We confirm the inclusion of Zora (formerly Zoridae) within Miturgidae.»

«Microglanis nigrolineatus, new species, is described from streams of Bermejo River basin, northwestern Argentina. It is distinguished from all congeners by a combination of characters including a unique coloration pattern: a thin dark line that runs along middle body from vertical line through dorsal-fin origin to end of adipose fin, delimiting two dark-brown areas ending in a dark blotch crossing entire body depth just anterior to caudal-fin origin and dorsal region of head uniformly dark, lacking a paler area on nuchal region. Also, thorn serrae on anterior margin of pectoral-fin spine are short.»

«Version 1.5 of the computer program TNT completely integrates landmark data into phylogenetic analysis. Landmark data consist of coordinates (in two or three dimensions) for the terminal taxa; TNT reconstructs shapes for the internal nodes such that the difference between ancestor and descendant shapes for all tree branches sums up to a minimum; this sum is used as tree score. Landmark data can be analysed alone or in combination with standard characters; all the applicable commands and options in TNT can be used transparently after reading a landmark data set. The program continues implementing all the types of analyses in former versions, including discrete and continuous characters (which can now be read at any scale, and automatically rescaled by TNT). Using algorithms described in this paper, searches for landmark data can be made tens to hundreds of times faster than it was possible before (from T to 3T times faster, where T is the number of taxa), thus making phylogenetic analysis of landmarks feasible even on standard personal computers.»

«A new species of the spider genus Actinopus Perty from cochabamba, Bolivia is described under the name of Actinopus cochabamba sp. n. this is the second species of the genus described for the country. Detailed morphological description and illustrations of the new species are presented.»

«Tinamous are volant terrestrial birds, endemic to the Neotropics. Here, an inclusive phenotype-based phylogenetic study of the interrelationships among all extinct and living species of tinamous is conducted. In this cladistic analysis, results are compared between main character subsets and with previous molecular studies. Special attention is paid to character definition and scoring of integumentary and behavioural characters: transformation costs are applied to analyse egg coloration and plumage characters—on the basis of pigment composition and overlap of pigmentation patterns respectively—in the context of generalized (Sankoff) parsimony. Cladistic analysis recovers the traditional subdivision between those tinamous specialized for open areas (Nothurinae) and those inhabiting forested environments (Tinaminae) and support the monophyly of recognized genera. The present study demonstrates that morphological analysis yields highly congruent results when compared with previous molecular studies; thus, it provides morphological synapomorphies for clades that have been proposed by these molecular analyses. The placement of the fossil species within the open-area (Nothurinae) and the forest-dwelling (Tinaminae) tinamous is also consistent with the palaeoenvironmental conditions inferred from the associated flora and fauna.»

«Bats (Chiroptera) represent the largest diversification of extant mammals after rodents. Here we report the results of a large-scale phylogeny of bats based on unconstrained searches for a data matrix of 804 non-chimeric, taxonomically updated bat terminals (796 species represented by a single terminal plus three species represented by ?2 genetically distinct subspecies), able to preliminary test the systematics of most groups simultaneously. We used nine nuclear and mitochondrial DNA sequence markers fragmentary represented for ingroups (c. 90% and 64% of extant diversity at genus and species level, respectively) and 20 diverse placental outgroups. Maximum Likelihood and Parsimony analyses applied to the concatenated dataset yielded a highly resolved, variously supported phylogeny that recovered the majority of currently recognized clades at all levels of the chiropteran tree. Calibration points based on 44 key fossils allowed the Bayesian dating of bat origins at c. 4 my after the K-Pg boundary, and the determination of stem and crown ages of intraordinal clades. As expected, bats appeared nested in Laurasiatheria and split into Yinpterochiroptera and Yangochiroptera. More remarkable, all polytypic, currently recognized families were monophyletic, including Miniopteridae, Cistugidae, and Rhinonycteridae, as well as most polytypic genera with few expected exceptions (e.g., Hipposideros). The controversial Myzopodidae appeared in a novel position as sister of Emballonuroidea—a result with interesting biogeographic implications. Most recently recognized subfamilies, genera, and species groups were supported or only minor adjustments to the current taxonomy would be required, except Molossidae, which should be revised thoroughly. In light of our analysis, current bat systematics is strongly supported at all levels; the emergent perception of a strong biogeographic imprint on many recovered bat clades is emphasized.»

«Commerson’s dolphin, Cephalorhynchus commersonii, is one of the smallest species of odontocete cetaceans. We aimed to study the postnatal cranial ontogeny of C. commersonii through geometric morphometric technique, analyzing the postnatal ontogeny of the symmetric and asymmetric components of shape and providing information about sexual dimorphism affecting cranial shape and size. We digitized 57 landmarks in a sample of 139 crania of an ontogenetic series. Our results indicate that C. commersonii presents sexual size dimorphism of cranium in adults, but not shape dimorphism. Major changes between juveniles and adults were associated with lengthening of the rostrum and accentuation of telescoping, as observed in other odontocetes. We found that the degree of asymmetry has a very subtle but still significant change during ontogeny, which may have functional implications. We also observed little general variation in skull shape during postnatal development, supporting the idea of the conservatism of young-like characters in adults of C. commersonii. In accordance with this, we detect a very early attainment of stability of shape and size, being statistically similar in males and females. Differences in overall cranial shape and growth patterns in C. commersonii and Pontoporia blainvillei can be functionally associated to specific modes of feeding, suggesting also differences in the melon morphology.»

«Oreobates Jiménez de la Espada, 1872 is a large group of South American frogs with terrestrial reproduction and direct development, located in the superfamily Brachycephaloidea. About 260 brachycephaloidean species have been cytogenetically studied so far, at least with standard techniques. However, this information represents fewer than 17% species of the family Craugastoridae Hedges, Duellman & Heinicke, 2008, where the genus Oreobates is included. In the present work, using a diversity of standard and molecular techniques, we describe the karyotype of O. barituensis Vaira & Ferrari, 2008, O. berdemenos Pereyra, Cardozo, Baldo & Baldo, 2014 and O. discoidalis (Peracca, 1895), from northwestern Argentina. The three species analyzed showed a diploid karyotype with 2n = 22 biarmed chromosomes, fundamental number (FN) = 44, nucleolus organizer regions (NORs) located pericentromerically on pair 7, and a centromeric and pericentromeric C-banding pattern. We observed variations in the chromosome number in O. barituensis due the presence of two morphs of B chromosomes, one mediumsized telocentric (BT) and another subtelocentric and smaller (Bst). Both B chromosomes are mitotically stable and were recorded in all somatic and germinal cells analyzed. The BT chromosome occurred at a maximum of one per individual (2n = 22+BT), and the other one was observed single (2n = 22 + Bst) or as a pair in two doses (2n = 22 + 2BT). We additionally observed other supernumerary chromosomes in the three species analyzed, all of them euchromatic, small, dot-shaped and with instability during mitoses, showing a frequency of occurrence below 50% in studied specimens. The occurrence of polymorphic and spontaneous chromosomal rearrangements and supernumerary chromosomes is a recurrent feature reported in frogs with terrestrial habits (Brachycephaloidea and Hemiphractidae Peters, 1862), which suggests that Brachycephaloidea may be a promising group for studying the origin and maintenance of B chromosomes in anurans.»

«Oreobates Jiménez de la Espada, 1872 is a large group of South American frogs with terrestrial reproduction and direct development, located in the superfamily Brachycephaloidea. About 260 brachycephaloidean species have been cytogenetically studied so far, at least with standard techniques. However, this information represents fewer than 17% species of the family Craugastoridae Hedges, Duellman & Heinicke, 2008, where the genus Oreobates is included. In the present work, using a diversity of standard and molecular techniques, we describe the karyotype of O. barituensis Vaira & Ferrari, 2008, O. berdemenos Pereyra, Cardozo, Baldo & Baldo, 2014 and O. discoidalis (Peracca, 1895), from northwestern Argentina. The three species analyzed showed a diploid karyotype with 2n = 22 biarmed chromosomes, fundamental number (FN) = 44, nucleolus organizer regions (NORs) located pericentromerically on pair 7, and a centromeric and pericentromeric C-banding pattern. We observed variations in the chromosome number in O. barituensis due the presence of two morphs of B chromosomes, one mediumsized telocentric (BT) and another subtelocentric and smaller (Bst). Both B chromosomes are mitotically stable and were recorded in all somatic and germinal cells analyzed. The BT chromosome occurred at a maximum of one per individual (2n = 22 + BT), and the other one was observed single (2n = 22 + Bst) or as a pair in two doses (2n = 22 + 2BT). We additionally observed other supernumerary chromosomes in the three species analyzed, all of them euchromatic, small, dot-shaped and with instability during mitoses, showing a frequency of occurrence below 50% in studied specimens. The occurrence of polymorphic and spontaneous chromosomal rearrangements and supernumerary chromosomes is a recurrent feature reported in frogs with terrestrial habits (Brachycephaloidea and Hemiphractidae Peters, 1862), which suggests that Brachycephaloidea may be a promising group for studying the origin and maintenance of B chromosomes in anurans.»

«Objetivo: Describir por primera vez el desempeño de un collar de telemetría GPS en el seguimiento a un oso andino silvestre en los ecosistemas montañosos de los Andes colombianos (Cundinamarca, Colombia), como un aporte al conocimiento de la efectividad de esta técnica en la especie. Metodología: Se relacionó el número de posiciones GPS obtenidas y esperadas, el número de satélites enlazados, tipo de posición (2D, 3D), valores de dilusión horizontal de precisión, tiempo para la primera posición, estado de actividad-inactividad del oso y horas de día (luz: 05:00-18:00) o noche (oscuridad: 01:00-04:00 y 19:00-24:00) en que fueron obtenidos estos datos. Resultados: Existió diferencia significativa en la actividad del oso marcado, mostrándolo activo durante el día e inactivo en la noche (M-Wt, p=4.456E-38). No existió diferencia en el éxito de posiciones entre día-noche (t test, p=0.50) o entre actividad-inactividad (t test, p=0.73), sin embargo la actividad se correlacionó positivamente con el número de satélites (p=3.781E-5, r=0.22) y negativamente con los valores HDOP (p=1.583E-11, r=-0.35) y TTFF (p=8.911E-12, r=-0.36). Una vez en funcionamiento, el collar asumió una programación diaria de toma de posiciones distinta a la establecida, y dejó de funcionar súbitamente a los 41 días de seguimiento, permitiendo un éxito de posiciones de 5.3% respecto a lo esperado para 12 meses. Conclusiones: Durante el funcionamiento del dispositivo los patrones de actividad de esta especie y las coberturas boscosas/rocosas asociadas con su descanso nocturno, no afectaron negativamente el éxito de toma de posiciones, pero sí la calidad de las mismas. El daño prematuro del collar y el cambio arbitrario que asumió sobre la programación diaria de toma de posiciones, indican que el dispositivo evaluado no mostró un buen desempeño para el seguimiento del oso marcado.»

«Hoffmann's two-toed sloth (Choloepus hoffmanni) has been extensively studied since the 1940s in some countries across its distribution range. However, several aspects of its biology remain unexplored or have been described superficially. This study updated the geographic distribution of this sloth species in Colombia, describing external traits of specimens that inhabit different areas of the country. Additionally, a revision of the current state of knowledge of this species in Colombia was conducted, with a focus on the identification of information gaps and the major threats affecting this species. An updated map of the distribution of C. hoffmanni in Colombia was elaborated, including the distribution reported by IUCN, the records of specimens received in the Xenarthra center for rescue and rehabilitation (CRRX, for its acronym in Spanish; primary information), the wildlife care centers of the Autonomous Regional Corporations (CARs, for its acronym in Spanish), and records of biological collections available online (secondary information). CRRX specimens were examined externally, and the external morphological characteristics (skull and body shape; pelage color, length and density) were described. A comprehensive literature review was performed, compiling studies conducted over the last two decades on this species in Colombia, analyzing their respective contributions to its knowledge. The records obtained provide localities of occurrence for the species not previously recognized by IUCN, in 54 municipalities of 12 departments of Colombia. There are external morphological patterns defining lowland (interandean valleys and Caribbean region), highland (Colombian Andes) and Colombian Pacific populations. The biggest information gaps regard demography, distribution and genetics. The main threats identified are habitat loss (infrastructure construction, forest clearance) and removal of specimen (illegal trade). The localities of occurrence obtained confirm the distribution of this species in areas previously suggested at the north and center of the Cordillera Occidental, Cordillera Central and Cauca River valley, besides the north, center and south of the Cordillera Oriental, Piedemonte Llanero, and the southern Magdalena River valley. The external revision of specimens from the CRRX shows that although it is impossible to derive clear taxonomic inferences from the evidence collected, pelage color, length and density are the most representative external traits that differentiate lowland, highland and Pacific Colombian populations. The prioritization of issues such as the conservation status and threats in the investigation of this species in Colombia during the last twenty years have relegated key aspects such as demography, distribution, taxonomy and genetics, a fact that poses a challenge for the execution of proper management actions in the country.»

«Thyroptera tricolor is a rarely collected bat species that inhabits lowland forests in Central and South America. We review the distribution of T. tricolor in Colombia, using previous and new records deposited in scientific collections of the world, providing a distribution map and a gazetteer with comments on available geographical information. We also provide first records for the Middle Magdalena Valley, with external and cranial measurements. These new records reduce the distributional gap between northern and southern records of the country. Additionally, by comparing dental measurements of our recent specimens with fossil records of thyropterids from the Magdalena Valley (La Venta deposits), we contribute to understanding the evolution and distribution of this group, reinforcing the hypothesis of evolutionary stasis.»

«Intense sampling in the upper Bermejo River basin revealed the presence of specimens of the aspredinid genus Bunocephalus. After detailed morphological and morphometric analyses specimens were identified as Bunocephalus doriae. This is the first record of any member of the Aspredinidae in the upper Bermejo River basin.»

«We present a new record for Austrolebias elongatus from Gualeguaychú, in Entre Ríos Province, Argentina, based on new fieldwork and a revision of material deposited in national ichthyological collections. We also give evidence on the erroneous records of Austrolebias monstrosus and A. vandenbergi from Ituzaingó, Corrientes Province, as well as present additional records from Salta Province for those species. Material previously determined as A. elongatus from Santiago del Estero is attributed to A. monstrosus. We restrict the distribution of these two species to Semi-arid Chaco Region in Argentina, Paraguay and Bolivia.»

«At least five different reproductive modes were reported in the neotropical frog genus Leptodactylus, all of them involving the building of foam nests. We analyzed the early ontogeny of five species of the L. fuscus group building terrestrial chambers where eggs are deposited, and of two species of the L. latrans group constructing a floating nest over the surface of lentic waters. The ontogenetic period described herein includes the occurrence of exclusively embryonic structures and the initial stages of development of larval features. In a likely relation to ecological aspects of oviposition and developmental mode, embryos of these two groups differ in several features. Embryos of the L. fuscus group were mainly pigmentless, were large sized with an extensive yolk provision, showed a dorsal kyphosis and lacked adhesive glands. Conversely, embryos of the L. latrans group were darkly pigmented, lacked a dorsal curvature, were comparatively smaller and less yolked, and showed adhesive glands in a peculiar type D morphogenetic pattern. Embryos of the L. latrans group had long, profusely branched, highly ciliated external gills, which were arranged ventrally. The comparative analysis of developmental sequences revealed an early emergence of hind limbs in Leptodactylus species relative to a reference leiuperine trajectory, an earlier differentiation of external gills in the species of the L. fuscus group, and an overall earlier development of mouthparts in embryos of the L. latrans group. Further analyses in a phylogenetic context are needed to evaluate the ancestral reconstructions of the development sequence and detect evolutionary relevant heterochronies in the genus.»

«Most extant New World marsupials belong in the Didelphidae, which comprises ca. 110 currently recognized species of opossums. Didelphids are small mammals with their mean body mass, at species level, ranging from ca. 7 g to 2.2 kg. The largest species belong in a single clade, while substantial variation remains scattered across the remaining groups. We seek out to explore the details of this mass variation in an evolutionary framework. To this end, we first reconstructed the phylogeny of didelphids based on an extensive, although fragmentary sample of sequences from ten genes. We recovered a fully resolved, highly robust phylogeny that tested and confirmed most previously reported groupings, providing a simultaneous depiction of phylogenetic relationships for 81% of currently recognized species and all relevant supra-specific clades. As much as 69% of total body mass variation in didelphids was explained by this phylogenetic hypothesis. Mapped on it, mass variation evolved as much as 6.8 kg of total changes, starting from a reconstructed ancestral body mass range of 22–33 g. No single, family-wide pattern was evident; in fact, the dominant pattern for mass variation was that of increases in body mass along a few successive branches, or phyletic giantism, followed by apomorphic nanism, i.e., decreases localized in single terminal branches. Phyletic trends indicated the persistence of gradual, directional changes along considerable spans of geological time and show that substantial variation of interest resides in this and perhaps most groups of small mammals.»

«This paper examines a recent proposal to calculate supertrees by minimizing the sum of subtree prune-and-regraft distances to the input trees. The supertrees thus calculated may display groups present in a minority of the input trees but contradicted by the majority, or groups that are not supported by any input tree or combination of input trees. The proponents of the method themselves stated that these are serious problems of “matrix representation with parsimony”, but they can in fact occur in their own method. The majority rule supertrees, being explicitly clade-based, cannot have these problems, and seem much more suited to retrieving common clades from a set of trees with different taxon sets. However, it is dubious that so-called majority rule supertrees can always be interpreted as displaying those clades present (or compatible with) with a majority of the trees. The majority rule consensus is always a median tree, in terms of the Robinson–Foulds distances (i.e. it minimizes the sum of Robinson–Foulds distances to the input trees). In contrast, majority rule supertrees may not be median—different, contradictory trees may minimize Robinson–Foulds distances, while their strict consensus does not. If being “majority” results from being median in Robinson–Foulds distances, this means that in the supertree setting a “majority” is ambiguously defined, sometimes achievable only by mutually contradictory trees.»

«In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonidae. These species vary in their ovipositional mode and the type of environments where the embryos and tadpoles develop, including ponds, streams, and axils of leaves of terrestrial or epiphytic plants. Comparative anatomical studies and sequence heterochrony analyses show that primary morphological variations occur in the morphology at the tail-bud stage, the arrangement and development of the external gills, adhesive gland type and division timing, growth of the dorsal hatching gland on the head, configuration of the oral disc, emergence and development of the hind limbs, and presence of the abdominal sucker. Some of these transformations are best explained by phylogeny (e.g., early divergent taxa of bufonids have embryos with kyphotic body curvature, Type C adhesive glands, and a very small third pair of gills). Other traits might be correlated with reproductive modes (e.g., phytotelmata embryos hatch comparatively late and show an accelerated development of hind limbs). Because these actual variations are not well studied (e.g., less than the 10% of the known diversity of bufonids has been studied from this perspective), comprehensive analyses are required to interpret character evolution and the relationship with reproductive modes within the family.»

«In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonidae. These species vary in their ovipositional mode and the type of environments where the embryos and tadpoles develop, including ponds, streams, and axils of leaves of terrestrial or epiphytic plants. Comparative anatomical studies and sequence heterochrony analyses show that primary morphological variations occur in the morphology at the tail-bud stage, the arrangement and development of the external gills, adhesive gland type and division timing, growth of the dorsal hatching gland on the head, configuration of the oral disc, emergence and development of the hind limbs, and presence of the abdominal sucker. Some of these transformations are best explained by phylogeny (e.g., early divergent taxa of bufonids have embryos with kyphotic body curvature, Type C adhesive glands, and a very small third pair of gills). Other traits might be correlated with reproductive modes (e.g., phytotelmata embryos hatch comparatively late and show an accelerated development of hind limbs). Because these actual variations are not well studied (e.g., less than the 10% of the known diversity of bufonids has been studied from this perspective), comprehensive analyses are required to interpret character evolution and the relationship with reproductive modes within the family.»

«In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonidae. These species vary in their ovipositional mode and the type of environments where the embryos and tadpoles develop, including ponds, streams, and axils of leaves of terrestrial or epiphytic plants. Comparative anatomical studies and sequence heterochrony analyses show that primary morphological variations occur in the morphology at the tail-bud stage, the arrangement and development of the external gills, adhesive gland type and division timing, growth of the dorsal hatching gland on the head, configuration of the oral disc, emergence and development of the hind limbs, and presence of the abdominal sucker. Some of these transformations are best explained by phylogeny (e.g., early divergent taxa of bufonids have embryos with kyphotic body curvature, Type C adhesive glands, and a very small third pair of gills). Other traits might be correlated with reproductive modes (e.g., phytotelmata embryos hatch comparatively late and show an accelerated development of hind limbs). Because these actual variations are not well studied (e.g., less than the 10% of the known diversity of bufonids has been studied from this perspective), comprehensive analyses are required to interpret character evolution and the relationship with reproductive modes within the family.»

«Poco se conoce sobre la diversidad y morfología del género neotropical Actinopus Perty, 1833.En el presente trabajo se centra la atención en la variación intraespecífica de caracteres somáticos (cefalotórax y esternón) y genitales (bulbos copuladores) en una muestra de machos de Actinopus sp. Con el fin de cuantificar el cambio en la forma del esternón se aplicaron técnicas de morfometría geométrica. El análisis de una sub-muestra mostró bajos niveles de variación en ambos grupos de caracteres. El resultado sugiere un alto grado de conservación de los caracteres genitales y somáticos de estos machos.»

«We evaluated the directional asymmetry between right and left wings and quantified the intraspecific and interspecific variation of the wing shape of 601 specimens of the genus Diachlorus to determine to what extent the geometrical variation discriminates six species distributed in six protected areas of Colombia. Geometric analyses were performed, integrating Procrustes methods, principal component analyses, cluster analyses, linear and quadratic discriminant analyses, and evaluations of shape changes. In Diachlorus, left and right wings did not present significant asymmetry but a geometrical analysis was allowed for species identification and, in some cases, the origin of the specimens using the variation of wing shape; the best-assigned species was Diachlorus leticia Wilkerson & Fairchild, while the worst was Diachlorus jobbinsi Fairchild, which also had the highest intraspecific variation, while Diachlorus fuscistigma Lutz had the lowest variation. Diachlorus fuscistigma and Diachlorus leucotibialis Wilkerson & Fairchild were the most similar species, while D. leucotibialis and Diachlorus nuneztovari Fairchild & Ortiz were the most disimilar. The specimens with the most different wing shape belonged to Chocó (especially those of D. jobbinsi), the geographically farthest area from the others in the study; however, no correlation was observed between geometric and geographical distances. Linear discriminants were better than nonlinear (quadratic) discriminant analyses in predicting species membership, but the opposite was true for predicting area membership. Based on our data, we hypothesized that other species of Diachlorus could also be discriminated using geometric morphometry of the wing shape.»

«The maturation of mammalian carnivores from a lactating juvenile to a predatory adult requires a suite of changes in both morphology and behaviour. Bobcats (Lynx rufus (Schreber, 1777)) are medium-sized cats with well-developed skulls to process large prey that can exceed their body mass. An integrated view of the skull ontogeny in the bobcat was developed to detect the relationship between shape, size (on the basis of three-dimensional geometric morphometric analysis), and life history. Dietary changes from juvenile to adults were taken into account and compared with other carnivores. Newborns were different from the remaining age stages in the behavioral and morphological characters examined, which allows us to relate them to the terminal morphology reached during the prenatal period. All findings were related to the reinforcement of the skull and the enhancement of predatory skills in adult bobcats. The final cranial shape is reached in A2 age class, after 2 years of age, and once sexual maturity has been reached. This is a pattern not followed for the rest of carnivores previously studied, which might be related to the capacity of subduing prey that exceed them in size, a behavior not common in felids of the body size of bobcats.»

«In recent years, several publications in computer science journals have proposed new heuristic methods for parsimony analysis. This contribution discusses those papers, including methods highly praised by their authors, such as Hydra, Sampars and GA + PR + LS. Trees of comparable or better scores can be obtained using the program TNT, but from one to three orders of magnitude faster. In some cases, the search methods are very similar to others long in use in phylogenetics, but the enormous speed differences seem to correspond more to poor implementations than to actual differences in the methods themselves.»

«Los programas de conservación de especies amenazadas constituyen una herramienta útil para la planeación y ejecución de acciones coordinadas que influyan en el mejoramiento de la salud de las poblaciones de estas especies. Sin embargo, en Colombia es desconocido el impacto real que estos programas tienen al interior de las instituciones encargadas de ejecutarlos. Objetivo: Realizar una evaluación del estado de aplicación del Programa Nacional para la Conservación en Colombia del Oso Andino (PNOA) al interior de 26 corporaciones autónomas regionales (CAR) y la Oficina de Planeación de Parques Nacionales Naturales, Unidad Administrativa Especial de Parques Nacionales Naturales (UAESPNN). Metodología: Se realizó una revisión cuantitativa mediante los criterios de semáforo, sobre la información obtenida de 42 documentos institucionales de planeación y de las respuestas al requerimiento 2100-2-91674 de 2009 del Ministerio de Ambiente, Vivienda y Desarrollo Territorial (MAVDT), así como también de entrevistas con funcionarios. Resultados: Con excepción de una, la totalidad de las CARs presentaron información sobre la ejecución del programa en sus jurisdicciones (96,2%). La oficina de UAESPNN no presentó información física o virtual de sus jurisdicciones, impidiendo su inclusión integral en el análisis cuantitativo. En total, la línea de acción del PNOA con mayor porcentaje de aplicación directa fue la línea I (conservación in situ: 30,8%), la de mayor porcentaje de aplicación indirecta fue la línea V (fortalecimiento institucional: 88,5%) y la de mayor porcentaje de no aplicación fue la línea II (conservación ex situ: 42,3%). Conclusiones: El PNOA presenta una ejecución mayoritariamente indirecta donde 61,5% de las CARs evaluadas sólo habían desarrollado actividades indirectas, asociadas con la ejecución de otros programas nacionales de conservación. Se evidencia un vacío administrativo al interior de las CARs en relación con la ejecución del PNOA, en donde las acciones ejecutadas por las mismas en relación con este provienen más de acciones coyunturales que de la planeación institucional, reflejando que este programa no ha sido asimilado aún de forma estructural.»

«El orden Carnivora constituye uno de los grupos de fauna que más ha llamado la atención del hombre. A través de la historia, las comunidades humanas se han beneficiado de estos mamíferos en varios sentidos. Muchas especies han sido cazadas con fines medicinales, de consumo, de vestido, o para ser mantenidas como mascotas. Ecológicamente, los carnívoros ocupan los niveles más altos de las cadenas tróficas y juegan un papel importante en el control de poblaciones de vertebrados. Además, al ser considerados especies carismáticas, los carnívoros juegan un papel importante como objetivo central de programas de conservación de vida silvestre. Sin embargo, a pesar de su gran importancia económica, ecológica y cultural, y a que ocupan todos los ecosistemas del país, el conocimiento sobre la ecología y taxonomía de este grupo de fauna es escaso y en algunos casos no confiable o verificable. Adicionalmente, en muchas ocasiones el acceso a la información es limitado o se presenta en un lenguaje complejo para la comunidad en general. Esta situación dificulta la integración de datos que favorezcan la implementación de planes de manejo y conservación en proyectos de investigación y consultoría. Ante esta problemática, uno de los primeros pasos consiste en recopilar información que permita sentar bases para el diseño de investigaciones, planes de manejo o programas educativos pertinentes con las necesidades del campo y el manejo de la biodiversidad. La guía Los carnívoros terrestres y semiacuáticos continentales de Colombia quiere postularse como una herramienta que pueda ser utilizada por todos aquellos involucrados en el uso, el manejo y la conservación de estos mamíferos. A través de un formato de fichas técnicas, la publicación incluye información sobre las características morfológicas, ecológicas y de distribución para 28 especies del orden registradas en el país. Además, se sintetizan algunos datos de los ejemplares depositados en la colección de mastozoología del Instituto de Ciencias Naturales de la Universidad Nacional de Colombia (ICN), un patrimonio científico de incalculable valor para el entendimiento de la diversidad biológica y cultural nacional. Este ejercicio de investigación y divulgación contó con el apoyo de la Dirección de Bienestar Universitario de la Universidad Nacional de Colombia, la cual incentiva la realización de proyectos que promuevan la difusión de actividades estudiantiles de carácter social, académico y cultural. Cada día se incrementa el número de personas que se vinculan al mundo de la mastozoología a través de investigaciones, actividades de consultoría, espacios académicos o por interés personal. En este sentido, la guía constituye una herramienta no solo para los mastozoólogos del país, sino para todos aquellos involucrados en el uso, el manejo y la conservación de este grupo de fauna en el Neotrópico. Esperamos que este trabajo sirva de ejemplo no solo sobre la importancia de las colecciones biológicas como fuente de información, sino también como puente entre la academia, los grupos estudiantiles y los actores involucrados en el uso y manejo de nuestra biodiversidad.»

«The presence of a gill-derived gland is herein reported for the first time in males of species of Astyanax and related genera; they are described through histological cuts and SEM. The gill-derived glands described for the Characidae, when fully developed, present a similar structure in different species. The main external feature of gill-derived glands is the fusion of anteriormost gill filaments on the ventral branch of first gill arch. This fusion is caused by squamous stratified epithelial tissue that covers adjacent filaments, forming a series of chambers. In the region where the gill-derived gland develops, the secondary lamellae of the gill filaments are much reduced or completely atrophied being characterized by the presence of glandular cells forming nests.»

«Quantitative analyses of areas of endemism have rarely considered higher taxa. This paper discusses aspects related to the use of higher taxa in the analysis of areas of endemism, and computer implementations. An example of the application of the method is provided, with a data set for Nearctic mammals, showing that some of the areas recognized by species-level taxa also adjust well to the distribution of other taxa of higher level (genera, monophyletic groups).»

«Bats possess a series of patagial tracts that together act as an aerofoil for powered flight. Here we discuss the homology of a small portion of the patagium, the brevis section, traditionally assigned as a part of the handwing (dactilopatagium). Using dissected specimens and literature references we show that the muscle occipitopollicalis, a morphological marker of the propatagium, extends into the brevis section in a variety of bats. This led us to conclude that the brevis section is in fact a part of the propatagium, which is also supported by developmental evidence.»

«This paper describes an efficient implementation of triplet-based measures of stability, in the program TNT. The only available implementations of such measures are much slower than the present one, either because of an inefficient implementation (Phyutility, Thor) or because the stability is evaluated with quartets (RogueNaRok, requiring O(t4), instead of the O(t3) possible for triplets). The method to quickly calculate triplets is applied to solving IterPCR (Pol and Escapa, 2009). It is shown that, in some cases, IterPCR or other algorithms in the program TNT (e.g. commands prunnelsen, prunmajor, or chkmoves) produce more informative results than analysis with RogueNaRok.»

«Durante cinco meses (febrero–junio 2014) se rescató y reubicó fauna como parte de las labores de adecuación del vaso del embalse del Proyecto Hidroeléctrico Sogamoso (Santander-Colombia). Se realizaron 71 capturas de especies del orden Pilosa, que correspondieron a densidades de 0.4, 0.35 y 0.06 (ind/ha) para Bradypus variegatus, Choloepus hofmanni y Cyclopes didactylus, respectivamente. La proporción de sexos fue 1?:1? para B. variegatus y 1?:2.2? para C. hofmanni. El cuidado de crías se observó entre marzo y junio para B. variegatus y C. hofmanni, mientras que la gestación solo en mayo para C. hofmanni. Se recomienda documentar los rescates de fauna, minimizando la pérdida de datos biológicos valiosos de las especies afectadas.»

«In this paper I summarize the morphology of the Leptodactylus plaumanni tadpoles, describing the external morphology, buccal cavity, and cranial skeleton and associated muscles. A distinctive combination of traits include the truncated snout in dorsal view, dorsal fin originated anterior to the body-tail junction, submarginal papillae present in some specimens, two slight indentations in the lower lip, ceratobranchial III free from the hypobranchial plate, small ventrolateral projections of the corpus of the suprarostral cartilage, m. subarcualis rectus I with three heads, and m. subarcualis rectus II–IV inserting in ceratobranchial I and connective tissue between branchial processes II and III. The buccal cavity shares the typical features in species of the group, namely four lingual papillae, two pairs of infralabial papillae, two postnarial papillae, and one pair of not branched lateral ridge papillae. Attending to the increasing role of larval characters in phylogenetic analyses, further research is needed to understand the evolution of tadpole morphology in this genus.»

«Although the use of landmark data to study shape changes along a phylogenetic tree has become a common practice in evolutionary studies, the role of this sort of data for the inference of phylogenetic relationships remains under debate. Theoretical issues aside, the very existence of historical information in landmark data has been challenged, since phylogenetic analyses have often shown little congruence with alternative sources of evidence. However, most analyses conducted in the past were based upon a single landmark configuration, leaving it unsettled whether the incorporation of multiple configurations may improve the rather poor performance of this data source in most previous phylogenetic analyses. In the present study, we present a phylogenetic analysis of landmark data that combines information derived from several skeletal structures to derive a phylogenetic tree for musteloids. The analysis includes nine configurations representing different skeletal structures for 24 species. The resulting tree presents several notable concordances with phylogenetic hypotheses derived from molecular data. In particular, Mephitidae, Procyonidae, and Lutrinae plus the genera Martes, Mustela, Galictis, and Procyon were retrieved as monophyletic. In addition, other groupings were in agreement with molecular phylogenies or presented only minor discordances. Complementary analyses have also indicated that the results improve substantially when an increasing number of landmark configurations are included in the analysis. The results presented here thus highlight the importance of combining information from multiple structures to derive phylogenetic hypotheses from landmark data.»

«Oblong, a program with very low memory requirements, is presented. It is designed for parsimony analysis of data sets comprising many characters for moderate numbers of taxa (the order of up to a few hundred). The program can avoid using vast amounts of RAM by temporarily saving data to disk buffers, only parts of which are periodically read back in by the program. In this way, the entire data set is never held in RAM by the program—only small parts of it. While using disk files to store the data slows down searches, it does so only by a relatively small factor (4× to 5×), because the program minimizes the number of times the data must be accessed (i.e. read back in) during tree searches. Thus, even if the program is not designed primarily for speed, runtimes are within an order of magnitude of those of the fastest existing parsimony programs.»

«A new species of the spider genus Actinopus Perty 1833 from Northwestern Argentina is described—Actinopus goloboffi sp. nov. This is the second species described from the genus in the country. Detailed morphological descriptions of both sexes, illustrations and geographic distribution of the new species are presented.»

«When doing a bootstrap analysis with a single tree saved per pseudoreplicate, biased search algorithms may influence support values more than actual properties of the data set. Two methods commonly used for finding phylogenetic trees consist of randomizing the input order of species in multiple addition sequences followed by branch swapping, or using random trees as the starting point for branch swapping. The randomness inherent to such methods is assumed to eliminate any consistent preferences for some trees or unsupported groups of taxa, but both methods can be significantly biased. In the case of trees created by sequentially adding taxa, a bias may occur even if every addition sequence is equiprobable, and if one of the equally optimal positions for each terminal to add to the tree is selected equiprobably. In the case of branch swapping, the bias can happen even when branch swapping equiprobably selects any of the trees of better score in the subtree-pruning-regrafting-neighborhood or tree-bisection-reconnection-neighborhood. Consequently, when the data set is ambiguous, both random-addition sequences and branch swapping from random trees may (i) find some of the optimal trees much more frequently than others and (ii) find some groups with a frequency that differs from their frequency among all optimal trees. When the data set defines a single optimal tree, the groups present in that tree may have a different probability of being found by a search, even if supported by equal amounts of evidence. This may happen in both parsimony and maximum-likelihood analyses, and even in small data sets without incongruence.»

«We re-analyzed 10 sparse supermatrices wherein the original authors relied primarily or entirely upon maximum likelihood phylogenetic analyses implemented in RAxML and quantified branch support using the bootstrap. We compared the RAxML-based topologies and bootstrap values with both superficial- and relatively thorough-tree-search parsimony topologies and bootstrap values. We tested for clades that were resolved by RAxML but properly unsupported by checking if the SH-like aLRT equals zero and/or if the parsimony-optimized minimum branch length equals zero. Four of our conclusions are as follows. (1) Despite sampling nearly 50,000 characters, highly supported branches in a RAxML tree may be entirely unsupported because of missing data. (2) One should not rely entirely upon RAxML SH-like aLRT, RAxML bootstrap, or superficial parsimony bootstrap methods to rigorously quantify branch support for sparse supermatrices. (3) A fundamental factor that favors thorough parsimony analyses of sparse supermatrices is being able to distinguish between clades that are unequivocally supported by the data from those that are not; superficial likelihood analyses that quantify branch support using the bootstrap cannot be relied upon to always make this distinction. (4) The SH-like aLRT and parsimony-optimized minimum-branch-length tests generally identify the same properly unsupported clades; the latter is a more severe test. »

«Several extensions to implied weighting, recently implemented in TNT, allow a better treatment of data sets combining morphological and molecular data sets, as well as those comprising large numbers of missing entries (e.g. palaeontological matrices, or combined matrices with some genes sequenced for few taxa). As there have been recent suggestions that molecular matrices may be better analysed using equal weights (rather than implied weighting), a simple way to apply implied weighting to only some characters (e.g. morphology), leaving other characters with a constant weight (e.g. molecules), is proposed. The new methods also allow weighting entire partitions according to their average homoplasy, giving each of the characters in the partition the same weight (this can be used for dynamically weighting, e.g. entire genes, or first, second, and third positions collectively). Such an approach is easily implemented in schemes like successive weighting, but in the case of implied weighting poses some particular problems. The approach has the peculiar implication that the inclusion of uninformative characters influences the results (by influencing the implied weights for the partitions). Last, the concern that characters with many missing entries may receive artificially inflated weights (because they necessarily display less homoplasy) can be solved by allowing the use of different weighting functions for different characters, in such a way that the cost of additional transformations decreases more rapidly for characters with more missing entries (thus effectively assuming that the unobserved entries are likely to also display some unobserved homoplasy). The conceptual and practical aspects of all these problems, as well as details of the implementation in TNT, are discussed.»

«Three different types of data sets, for which the uniquely most parsimonious tree can be known exactly but is hard to find with heuristic tree search methods, are studied. Tree searches are complicated more by the shape of the tree landscape (i.e. the distribution of homoplasy on different trees) than by the sheer abundance of homoplasy or character conflict. Data sets of Type 1 are those constructed by Radel et al. (2013). Data sets of Type 2 present a very rugged landscape, with narrow peaks and valleys, but relatively low amounts of homoplasy. For such a tree landscape, subjecting the trees to TBR and saving suboptimal trees produces much better results when the sequence of clipping for the tree branches is randomized instead of fixed. An unexpected finding for data sets of Types 1 and 2 is that starting a search from a random tree instead of a random addition sequence Wagner tree may increase the probability that the search finds the most parsimonious tree; a small artificial example where these probabilities can be calculated exactly is presented. Data sets of Type 3, the most difficult data sets studied here, comprise only congruent characters, and a single island with only one most parsimonious tree. Even if there is a single island, missing entries create a very flat landscape which is difficult to traverse with tree search algorithms because the number of equally parsimonious trees that need to be saved and swapped to effectively move around the plateaus is too large. Minor modifications of the parameters of tree drifting, ratchet, and sectorial searches allow travelling around these plateaus much more efficiently than saving and swapping large numbers of equally parsimonious trees with TBR. For these data sets, two new related criteria for selecting taxon addition sequences in Wagner trees (the ‘‘selected’’ and ‘‘informative’’ addition sequences) produce much better results than the standard random or closest addition sequences. These new methods for Wagner trees and for moving around plateaus can be useful when analyzing phylogenomic data sets formed by concatenation of genes with uneven taxon representation (‘‘sparse’’ supermatrices), which are likely to present a tree landscape with extensive plateaus.»

«Tinamous, one of the earliest diverging living avian lineages, consists of a Neotropical clade of palaeognathous birds with a fossil record limited to the early Miocene–Quaternary of southern South America. Here, we conduct a comprehensive, morphology-based phylogenetic study of the interrelationships among extinct and living species of tinamous. Morphological data of fossil species are included in a matrix of 157 osteological and myological characters of 56 terminal taxa. The monophyly of most recognized genera is supported by the results of the analysis. The cladistic analysis also recovers the traditional subdivision between those tinamous specialized for open areas (Nothurinae) and those inhabiting forested environments (Tinaminae). Temporal calibration of the resultant phylogeny indicates that such a basal divergence had already taken place in the early Miocene, some 17 million years ago. The placement of the fossil species within the open-area (Nothurinae) and the forest-dwelling (Tinaminae) tinamous is also consistent with the palaeoenvironmental conditions inferred from the associated fauna.»

«Empirical and simulated examples are used to demonstrate an artifact caused by undersampling optimal trees in data matrices that consist mostly or entirely of locally sampled (as opposed to globally, for most or all terminals) characters. The artifact is that unsupported clades consisting entirely of terminals scored for the same locally sampled partition may be resolved and assigned high resampling support—despite their being properly unsupported (i.e., not resolved in the strict consensus of all optimal trees). This artifact occurs despite application of random-addition sequences for stepwise terminal addition. The artifact is not necessarily obviated with thorough conventional branch swapping methods (even tree-bisectionreconnection) when just a single tree is held, as is sometimes implemented in parsimony bootstrap pseudoreplicates, and in every GARLI, PhyML, and RAxML pseudoreplicate and search for the most likely tree for the matrix as a whole. Hence GARLI, RAxML, and PhyML-based likelihood results require extra scrutiny, particularly when they provide high resolution and support for clades that are entirely unsupported by methods that perform more thorough searches, as in most parsimony analyses.»

«We describe an exceptionally well-preserved partial skeleton of a new bird from the early Eocene Fur Formation of Denmark. Like other fossils from these marine deposits, the partial skeleton is three-dimensionally preserved and articulated. This new Danish specimen consists of a skull, vertebral column, ribs, pelvis, and hindlimbs. Concerning characters of the pelvis, tibiotarsus and tarsometatarsus, the new fossil bears morphological affinities to charadriiform birds (shorebirds and relatives). A phylogenetic analysis of higher neomithine (modern birds) taxa also supports a close relationship between the new specimen and modern Charadriiformes. The morphologies of the skull and vertebrae, however, distinguish the new fossil from all recent charadriiform families.»

«For ambiguous data sets, methods to determine areas of endemism based on an optimality criterion may result in large numbers of candidate areas, and thus some kind of consensus technique is required to summarize those results. This paper presents a formal description of two possible algorithms or rules for area consensus, which merge candidate areas if they share a user-defined percentage of the species that define each candidate area. The two consensus rules summarize ambiguity in different ways. Applying the ‘tight’ rule will result in consensus areas defined by species present in nearly all cells, but in cases where there is significant conflict the result may be a high number of distinct consensus areas. The ‘loose’ consensus rule is more agglomerative and will result in fewer consensus areas, combining areas when overlapping distribution patterns exist. Depending on the aim and scale of the analysis, the two consensus rules can be used either to delimit areas of endemism with sharp boundaries or to identify diffuse and gradually replacing biogeographical patterns. These two different approaches are discussed and demonstrated using real data. »

«The Puma lineage is a monophyletic group that includes three living species: Puma concolor, Herpailurus yagouaroundi, and Acinonyx jubatus. It has been analysed from ecological and taxonomic perspectives, but their cranial ontogeny has been poorly studied. In this study, we assessed the cranial shape and size variation through three-dimensional geometric morphometric techniques, and explored the acquisition of definitive shape and size in relation to key life-history events. Each species occupied different locations in the shape morphospace: A. jubatus and P. concolor showed shorter and wider skulls, with more expanded zygomatic arches, than H. yagouaroundi, which presented the most divergent pattern of change. Ontogeny was more similar between P. concolor and A. jubatus than between the closely related P. concolor and H. yagouaroundi. The evolution of ontogenetic change in the lineage seems to be more influenced by size. Changes detected between juvenile and adult skulls enhanced predatory skills, coincident with the change from a diet of milk to a carnivorous diet. Change patterns suggest that the skull is not morphologically conservative in the lineage, in contrast with other carnivores such as canids and hyaenids. The enlargement of the rostrum observed in some canids and the reinforcement of the bite mechanism of hyaenids were not detected in this group.»