Abstract: The pollen morphology of seven species of the genus Adesmia (Fabaceae, Papilionoideae) that inhabit the mountainous region of northwest argentine was analyzed: A. cordobensis var cordobensis Burkart, A. incana Voguel var. incana, A. muricata var. dentata (Lag.) Benth, A. cytisoides Griseb., A. inflexa Griseb., A. trijuga Gillies ex Hook. & Arn, A. schickendanzii Griseb. Samples were taken from fresh material and were processed according to conventional techniques for acetolyzed and non-acetolyzed pollen. Pictures were taken with an optical microscope and a scanning electron microscope. These grains are isopolar, radially symmetric, tricolporate, microreticulate and heterobrochate. In acetolyzed material they are of medium size, prolate to prolate-spheroidal. In non-acetolyzed material they are small, oblate spheroidal with wide colpi in the equatorial plane, and sharp ends. Only in the case of A. schickendanzii the non-acetolyzed grain is medium size, prolate, with narrow colpi (4-5 μm) in relation to other species, and the endoapertures are lolongate, but not as prominent as in the others. With scanning electron microscope the presence of smooth margin or with few microperforations in A. cordobensis, var. cordobensis, A. muricata var. dentata, A. cytisoides y A. incana var. incana, A. cytisoides and A. incana is confirmed. In A. trijuga margin is densely microperforated, while A. inflexa lacks of margin and the irregular border of the colpi is observed. On the basis of the observations made, a key was developed to identify the species studied. The statistical analysis allowed to establish the differences that support their taxonomic classification.
Adesmia; Fabaceae; northwest of Argentina; pollen morphology; taxonomy