On a cranial bony nodular protuberance on Mourasuchus pattersoni Cidade et al. 2017 (Crocodylia, Alligatoroidea) from the late Miocene of Venezuela

Author(s)

Cidade, Giovanne M. ^[1] ; Solorzano, Andres ^{[2, 3]} ; Rincon, Ascanio D. ^[3] ; Hsiou, Annie Schmaltz ^[1] ; Barbosa, Fernando Henrique de S. ^[4]

Affiliation

^[1] Univ Sao Paulo, FFCLRP, Dept Biol, Sao Paulo - Brazil

^[2] Univ Concepcion, Fac Ciencias Quim, Concepcion - Chile

^[3] Inst Venezolano Invest Cient, Ctr Ecol, Lab Paleontol, Carretera Panamer, Caracas - Venezuela

^[4] Univ Fed Rio de Janeiro, Dept Geol, Programa Posgrad Geol, Rio de Janeiro, RJ - Brazil

• Document type: Journal article
• Source: HISTORICAL BIOLOGY; v. 31, n. 7, p. 866-871, AUG 9 2019.
• Web of Science Citations: 0

Abstract

Mourasuchus pattersoni, from the late Miocene Urumaco Formation of Venezuela, is the fourth and most recent species described for the genus. The holotype, and only known specimen, is comprised of an almost complete skull with both mandibular rami and several postcranial remains. In ventral view, the right palatine bone has a spherical, nodular bony protuberance located on the anterior portion, near the suture with the maxilla. Unfortunately, we cannot assign a specific diagnosis based only on macroscopic inspection. Its appearance, form and location are compatible with three conditions: torus palatinus, a common benign intraoral bone overgrowth; osteoma, a benign neoplasical overgrowth of the bone; and hamartoma, an overgrowth of normal bone tissue that can only be differed from an osteoma by histological features. While occurrences of torus palatinus or hamartomas are not yet known in the nonhominid vertebrate fossil record, there are previous records of osteomas in fossil vertebrates, including in crocodylians, such as a specimen assigned to `Crocodylus sp.' from the Eocene, aside from several records for living crocodylians. Future studies are needed to uncover an accurate diagnosis of this unusual structure and help increase our knowledge of paleopathology in fossil crocodylomorphs in general, especially in the Caimaninae clade. (AU)

• FAPESP's process: 13/04516-1 - Syatematic Revision of the Mourasuchus genus (Alligatoroidea, Caimaninae), one of the most peculiar crocodiles of the world
• Grantee: Giovanne Mendes Cidade
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 11/14080-0 - Cretaceous and Tertiary (Paleogene/Neogene) Squamates (Reptilia, Lepidosauria) from the Bauru, Aiuruoca and Acre basins: systematics, evolution and palaeoenvironments
• Grantee: Annie Schmaltz Hsiou
• Support Opportunities: Research Grants - Young Investigators Grants