Hemipenial morphology of Epictiavellardi (Laurent, 1984) (Leptotyphlopidae, Serpentes) with the proposition and discussion of two general hemipenial patterns within the genus Epictia

Scolecophidia (Squamata, Serpentes), commonly known as blindsnakes, wormsnakes or threadsnakes comprises a group of small snakes, with relatively few systematic and morphological studies when compared to Alethinophidia. Since the external morphology is very conserved amongst scolecophidians, internal morphological studies—such as the hemipenial morphology—are useful to unravel several systematic issues within the group. We aimed to describe the hemipenial morphology of Epictiavellardi (Epictinae, Leptotyphlopidae) based on 16 organs belonging to eight specimens. The organ is unilobed, with the body conspicuously narrower than the base and with the apex slightly expanded, without any macroscopic ornamentation. The comparison of the hemipenial morphology of E.vellardi with other hemipenes of Epictia spp. allowed us to identify two general morphological patterns for the genus, which are proposed and discussed in detail in the present study. The results found herein may be extremely relevant for future hemipenial descriptions. In addition, independent characters found in Types I and II (such as ornamentation, shape of base, body and apex) should be regarded for future systematic and evolutionary morphology studies within Leptotyphlopidae, in addition to assisting in the taxonomy and identification of species of the genus.