Out of sight, but not out of mind: a name for the Stefania (Anura: Hemiphractidae) from the summit of Murisipan-tepui (Bolivar State, Venezuela)

Previous molecular analyses of the frog genus Stefania have shown that species boundaries in that group are often difficult to delineate when solely based on morphology. As a consequence, taxonomically cryptic species are not uncommon in the genus. Several highland Stefania species remain to be described, some potentially critically endangered due to their highly restricted geographic ranges. One case is the microendemic Stefania population from the summit of Murisipan-tepui, a poorly explored table-top mountain in the Los Testigos Massif, a small tepui mountain range located north to the much larger Chimanta Massif in southern Venezuela. That population, mistaken as S. satelles for two decades, was later reported as Stefania sp. 2 and belongs to the S. ginesi clade. The new species is phylogenetically distinct but phenotypically similar to S. satelles, a taxon restricted to its type-locality, i.e. the summit of Aprada-tepui in Venezuela. The new species is described based on morphology and cranial osteology. Molecular divergences with S. satelles are high (> 8%) in the barcoding fragment of 16S rRNA. Amended definitions for the two other described species in the S. ginesi clade (S. ginesi and S. satelles) are also provided. The new species should be listed as critically endangered according to IUCN criteria.

Automated summary

Previous molecular analyses have shown that species boundaries are difficult to determine in the frog genus Stefania based solely on morphology. A new species, belonging to the S. ginesi clade, has been discovered in the highlands of Murisipan-tepui in southern Venezuela. This new species is phenotypically similar to S. satelles but phylogenetically distinct, with high molecular divergences (> 8%). The new species should be classified as critically endangered according to IUCN criteria.