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Research Articles

Vol. 2 No. 1 (2025)

Revision of ‘Aspidosaurus’ novomexicanus, a Permo-Carboniferous dissorophid from New Mexico

DOI
https://doi.org/10.26034/la.opal.2025.8456
Submitted
10 August 2025
Published
29-10-2025

Abstract

Aspidosaurusnovomexicanus is a poorly known dissorophid represented by the holotype (YPM VP 810), a badly preserved partial skeleton from Permo-Carboniferous deposits of New Mexico. Compared to Paleozoic dissorophid records in other parts of North America like Texas and Oklahoma, the New Mexico record remains relatively sparse and low in taxic diversity. Additionally, ‘A.novomexicanus is likely one of the earliest known records of dissorophids in North America. However, due to poor preservation of the holotype and a convoluted taxonomic history of species- and genus-level referral of specimens to this taxon and to other dissorophids, the concept of ‘A.novomexicanus and whether the holotype is sufficiently diagnostic to merit continued designation as a valid taxon remain unclear. Recent revision of Aspidosaurus demonstrates that this species does not belong in the genus, providing an impetus for a reassessment. Here I redescribe YPM VP 810 and situate it within the contemporary framework of dissorophid anatomy and taxonomy. Based on these findings, I conclude that the holotype is not diagnostic, rendering ‘Aspidosaurus novomexicanus’ to be designated as a nomen dubium, although it is possible that it may be conspecific with ‘Broiliellusreiszi.

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