SVP 2021 abstracts – 21: Barbourofelis is ‘a unique cat’ because it’s not a cat

Naples and Haji-Sheikh 2021 report:
“The sabertooth adaptation has appeared at least five times (twice in true felids, twice in pseudofelids and once in synapsids) in the evolution of carnivorans.”

What is a pseudofelid? A keyword search in Google comes back to this paragraph, the only time in the history of paleontology that it was used.

The family Barbourofelidae (= false saber-tooth cats).

“Many hypotheses have been advanced to explain the iterative appearance of this extremely specialized adaptation. Each sabertooth taxon that is discovered in the fossil record shows unique aspects of morphology that reflect different biomechanical considerations for the use of these canines.”

By contrast the large reptile tree (LRT, 1991 taxa) nests Barbourofelis (Fig. 1) with the South American marsupial sabertooth, Thylacosmilus (Fig. 2). Not sure why this interrelationhship has been overlooked until now. Barbourofelis entered the LRT a week ago.

“Our work is focused on explaining these anatomical differences and why they are important. This lion-sized sabertooth had the longest upper canines in absolute and relative terms among all taxa so far discovered with exaggerated upper canines. Barbourofelis fricki is distinguished by its elongated canines that are the most slender and highly recurved upper canines among
sabertooths.”

Similar to those in Thylacosmilus, though.

“Although strong and sharp-edged, the narrow shape and tapering anterior and poster edges of these canines renders them brittle, therefore requiring the highest possible precision in biting behavior to avoid breakage. This priority is reflected in many other cranial anatomical features, including a foreshortened rostrum, increased skull depth, in combination with a vertical occiput and a mandible with a reduced coronoid process and robust dependent flange.

Similar to those in Thylacosmilus, though.

“Concomitant with these cranial features is a reorientation of the masticatory muscles reflecting an increase in the dorsoventral component and the reduction of mediolateral mandibular movements.”

Similar to those in Thylacosmilus, though.

“Reconstruction of the cranium of this predator demonstrated that this animal had a larger head than would have been predicted, and that modifications of the anterior cervical vertebrae also contribute to enhanced dorsoventral movements of the head on the neck in B. fricki. Our work demonstrates that this animal probably showed body proportions that differed significantly from previous reconstructions as well as from other sabertooths.”

Funny how Naples and Hajii-Sheikh failed to mention Thylacosmilus.

References
Naples V and Haji-Sheikh MH 2021. Barbourofelis fricki — The head bone is connected to the neck bone or hoe to rebuild a unique cat.

htwiki/Barbourofelis

https://pterosaurheresies.wordpress.com/2021/10/28/barbourofelis-enters-the-lrt-as-a-sabertoothed-marsupial-not-a-big-cat/