Comparative Osteology of Montane Climbing Salamanders (Plethodontidae: Bolitoglossa Subgenus Magnadigita) from Nuclear Central America

Abstract

The skeletal features of six species of salamanders in the genus Bolitoglossa (subgenus: Magnadigita) were described and compared. Many osteological features of the Magnadigita subgenus were found to be highly conserved, such as the presence of bifurcated first caudal vertebrae and distal expansions on the terminal phalanges. Key traits were identified that were distinct among the species in this study, including the prefrontals and frontoparietal fenestrae; we suggest these traits may be useful in future taxonomic studies of Bolitoglossa. We also discuss the evolution of paedomorphosis and webbed feet in relation to Magnadigita. Bolitoglossa diaphora has highly webbed feet but lacks the osteological features typically associated with this paedomorphic trait, such as fused or accentuated elements, but rather has the osteological features typical of other Magnadigita.