Chromosome numbers, cytogenetic analysis and first karyotype descriptions of Doru lineare and D. luteipes (Dermaptera, Forficulidae, Insecta)

Abstract

 Holokinetic chromosomes lack of a primary constriction and they are mainly found in insects including order Dermaptera commonly known as “tijeretas”. Members of the genus Doru are pest predators on corn, sugar cane and cotton crops and they are widely distributed in South America. Two species occur in Argentina: D. lineare (Eschs.) and D. luteipes (Scudder). The material was collected in the province of Tucumán (Argentina). In order to stain the chromosomes, classical staining techniques as well as DAPI fluorescent method were applied. The comparative analysis between D. luteipes and D. lineare reveals that both taxa have a haploid formula n = 10 (9A + XY) and 2n = 20. In addition, numerous meiotic irregularities were found and holokinetic chromosomes that gradually vary in size and lack of primary constrictions were observed. Cytogenetic information of D. luteipes is presented for the first time, the first karyotype descriptions for both species are performed and it is discussed the possible diploid origin for the genus.