The identity of Apostolepis pymi and placement of A. quinquelineata in the synonymy of A. nigrolineata (Serpentes, Xenodontinae)

Abstract

The correct application of the names Apostolepis nigrolineata, A. quinquelineata, and A. pymi has been subject of considerable controversy. Based upon review of the literature and the characteristics used to distinguish these species from each other, we conclude that A. pymi is a valid species and that A. quinquelineata is a junior synonym of A. nigrolineata. They differ from each other in hemipenial morphology and coloration. The background color of A. nigrolineata is reddish brown (vs. brown in A. pymi). In addition, only the dorsal region of end of tail is covered by a black band in A. nigrolineata (vs. end of tail completely surrounded by a black band in A. pymi). Both species are sympatrically distributed along the lowlands of Amazonia but A. nigrolineata occurs in both western and eastern regions whereas A. pymi is restricted to eastern regions with additional records from the States of Amazonas, Rondônia, Mato Grosso and an endemic population in the state of Ceará, northeastern Brazil.