A large-sized mesoeucrocodylian from the Late Cretaceous of Brazil with possible neosuchian affinities

ABSTRACT

Most crocodyliforms of the Bauru Group were found in rocks of the Adamantina Formation, whereas the younger Marília Formation is almost devoid of such fossils. Here, we provide a detailed comparative description of MPMA 02–0005/87, a large skull roof found in Marília Formation deposits of the Monte Alto area, assigning it to a new crocodyliform. Despite its fragmentary nature and puzzling suit of characters, the new taxon possesses enough characters to reject its placement within Notosuchia, which is so far the only crocodyliform clade known from the Bauru Group. We tested its phylogenetic position with twodata matrices, both of which recovered the new taxon within Neosuchia and Eusuchia. Although the material does not preserve any eusuchian synapomorphy, a neosuchian affinity is supported by: anterior extension of the meatal chamber covered by the squamosal; constricted flange of the posterior process of the postorbital; poorly developed posterolateral process of squamosal. Finally, the large size estimated for the specimen, ranging from 2.98 to 5.88 metres, coupled with its possible neosuchian affinity, suggests a possible semiaquatic behaviour, an ecology rarely explored by the predominantly terrestrial crocodyliforms of the Bauru Group.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:3C7C9499-FFE3-4D5A-A90B-DE2E3572EF16

http://www.zoobank.org/urn:lsid:zoobank.org:pub:98FFC142-674F-464D-BCFD-721C608A2635

KEYWORDS:

• Notosuchia
• Neosuchia
• Eusuchia
• Crocodyliformes
• Bauru Group
• Marília Formation

Acknowledgments

We thank both Dr. Sandra Tavares, curator of the “Museu de Paleontologia Prof. Antonio Celso de Arruda Campos”, and Dr. Fabiano Iori for the loan of the specimen. TSF was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq grant number 165031/2018-2). PLG was supported by the National Science Foundation (NSF DEB 1754596). JCAM and PLG were supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES grant numbers 8887.572782/2020-00 and 88887.583087/2020-00). JCAM and MCL were supported by the São Paulo Research Foundation (FAPESP grant numbers 2021/1456-4 and 2020/07997-4). FCM was supported by Program 162 (Projetos De Cooperação em Pesquisa Entre o Brasil e a Alemanha - CAPES/DAAD -PROBRAL). TNT is made freely available through the Willi Henning Society.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/08912963.2022.2122822

Additional information

Funding

This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq 165031/2018-2), National Science Foundation (NSF DEB 1754596), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES 8887.572782/2020-00 and 88887.583087/2020-00), and São Paulo Research Foundation (FAPESP 2021/1456-4 and 2020/07997-4).