A revision of recent taxonomic changes to the eyelash palm pitviper, Bothriechis schlegelii (Serpentes, Viperidae)

Abstract

The taxonomy of the Bothriechis schlegelii species group has recently been expanded, nearly doubling the number of recognized species within this genus. However, the validity of these new species, defined primarily by mitochondrial DNA and without a robust evaluation of nuclear DNA and morphological data, warrants critical reassessment. This study re-examines the integrative data used in the initial analysis and employs additional visualizations of the genetic and morphological datasets. The results suggest that the genetic differences previously interpreted as species boundaries may instead reflect clinal variation, not independent lineages. Furthermore, DELINEATE species delimitation analysis and morphological assessments challenge the distinction of the proposed taxa. The findings indicate that only three species in the B. schlegelii group should be maintained as valid ( B. nigroadspersus , B. schlegelii , and B. supraciliaris ), while most taxa proposed by Arteaga et al. (2024) should be considered junior synonyms, or at most, as subspecies. This has significant implications for conservation priorities and resource allocation. In highlighting the need for a cautious and thorough approach to species delimitation, this study contributes to the broader discussion of taxonomic practices, the issue of taxonomic inflation, and their impact on biodiversity conservation.