Broiliellus reiszi: A New Dissorophid Temnospondyl From Early Permian New Mexico

A new dissorophid (Temnospondyli, Dissorophoidea) from the Early Permian of New Mexico (United States)

Authors:

1. Robert Holmes (a)
2. David S. Berman (b)
3. Jason S. Anderson (c)

Affiliations:

a. Department of Biological Sciences, University of Alberta, Alberta T6E 1A2, Canada

b. Section of Vertebrate Paleontology, Carnegie Museum of Natural History, 4400 Forbes Avenue, Pittsburgh, Pennsylvania 15213, USA

c. Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive, Calgary, Alberta T2N 4N1, Canada

Abstract:

An amphibian skull and partial skeleton found from the El Cobre Canyon Formation of New Mexico, USA, is identified as a new species of the dissorophoid temnospondyl genus Broiliellus. Significant anatomical features include: a relatively long, narrow preorbital region, with both nasals and vomers no more than half as wide anteriorly than posteriorly; extended ventral projection of the postorbital; a unilaterally retained lateral exposure of the ectopterygoid (in addition to the normally present lateral exposure of the palatine); supratemporal lacking a semilunar flange; highly vaulted vomers forming a median internasal septum; and an angular with a swollen posteroventral keel. Phylogenetic analysis strongly supports a sister group relationship with Broiliellus brevis and clearly distinguishes it from another dissorophoid, ‘B.’ novomexicanus from New Mexico. The medially restricted supraneural osteoderms are more similar to those seen in Cacops than Broiliellus, which reinforces the importance of avoiding using single ‘key features’ to discriminate taxa.