Open AccessEstágios de desenvolvimento de Mariliasuchus amarali, Crocodyliformes Mesoeucrocodylia da formação Adamantina, cretáceo superior da bacia Bauru, Brasil
Author(s) -
Felipe Mesquita de Vasconcellos,
Ismar de Souza Carvalho
Publication year - 2005
Publication title -
anuário do instituto de geociências
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.202
H-Index - 12
eISSN - 1982-3908
pISSN - 0101-9759
DOI - 10.11137/2005_1_49-69
Subject(s) - skull , juvenile , ontogeny , biology , anatomy , adductor muscles , holotype , cretaceous , zoology , paleontology , taxonomy (biology) , ecology , genetics
Mariliasuchus amarali Carvalho & Bertini, 1999 , a Mesoeucrocodylia from the Adamantina Formation (Bauru Basin, Upper Cretaceous) shows some adaptative features to terrestrial environments: short and high skull, lateral orbits, frontal external nares and reduction of the dental formula with specialization of the tooth crown morphology in incisiform, caniniform and molariform teeth. It has been included in the infraorder Notosuchia Gasparini, 1971. Three specimens of Mariliasuchus amarali, found near the municipality of Marília, São Paulo State were analysed. One of them, holotype of Mariliasuchus amarali (UFRJ DG 50-R), is a juvenile crocodylifom whereas the other two (UFRJ DG 105-R and UFRJ DG 106-R) are adult animals. These fossils allowed an analysis of the ontogenetic development patterns of this species. It was performed a comparison betweeen the mandibular, laterotemporal and supratemporal fenestrae and the skull sculpturing in the three specimens. The results show that Mariliasuchus acquire in the course of its ontogeny a thicker and stronger skull. The caudal migration of the laterotemporal fenestra and the size increase of the supratemporal fenestra probably indicate a wider use or strength of the adductor muscles during seizing and food processing.