On the Discovery of Bisexual Populations of the Parthenogenetic Lizard Leposoma percarinatum (Gymnophthalmidae), with Insights into the Origin of Parthenogenesis in Leposoma

Leposoma percarinatum is one of the two recognized parthenogenetic species in the lizard family Gymnophthalmidae, and only females have been reported to date. Here we report and describe the first known males attributed to the species from two localities of northwestern Amazonia. We compare the morphological variation (15 meristic and 10 discrete characters, all relevant to species identification in Leposoma) of males and females from these populations with that of specimens from unisexual populations to test the hypothesis that they belong to the same species. We did not find significant morphological differences between unisexual and bisexual populations, except for those associated with sexual dimorphism. Additionally, we reviewed literature dealing with the origin of parthenogenesis in L. percarinatum and we provide some insights into this subject, in view of the discovery of males in this species.