Osteology of the enigmatic threadsnake species Epictia unicolor and Trilepida guayaquilensis (Serpentes, Leptotyphlopidae) with generic insights

Anat Rec (Hoboken). 2021 Oct;304(10):2183-2197. doi: 10.1002/ar.24676. Epub 2021 Jun 8.

Abstract

Since the rearrangement of all leptotyphlopid species previously known as "Leptotyphlops" in Adalsteinsson et al. (2009)'s paper, several taxa have remained untested regarding their generic identity and have been assigned to different genera based on phenotypic data or, in some cases, without any clear justification. Most of the difficulties in assigning some leptotyphlopid taxa are due to their conserved external morphology, summed with a relatively small number of available specimens, which complicate the recognition of a unique combination of characters for their reasonable generic allocation. On the other hand, recent osteological studies-especially those on the skull-provide relevant data combinations for species assignment and even for the recognition of new genera. In this work, we have attempted to determine the generic allocation of Epictia unicolor and Trilepida guayaquilensis-both species currently known only by their holotype-based on a detailed description of cranial and post-cranial osteology. We confirm the assignment of E. unicolor to the genus Epictia despite the divergent configuration of cephalic shields. Based mainly on data from the skull, suspensorium, and cervical vertebrae but supported by external morphology as well as a redescription of the holotype, we propose the assignment of Trilepida guayaquilensis to the genus Epictia. This study provides not only detailed data on the osteology of Epictia, but also a first approach to the putative combination of osteological characters for the genus.

Keywords: HRXRT; burrowing snakes; internal morphology; systematics; taxonomy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Osteology*
  • Snakes*