Baurusuquídeos da Bacia Bauru (Cretáceo Superior, Brasil)

The baurusuchids are medium-sized crocodylomorphs withterrestrial habits, found in the Gondwana Cretaceous basins of SouthAmerica and Paleogene basins of Europe and Africa. Since 1945 manyskeletal remains have been found on Western of São Paulo State, rocks of Adamantina Formation, Bauru Basin (Late Cretaceous). Thevicinities of General Salgado County, São Paulo State, had revealedwell-preserved and articulated fossils of baurusuchids, allowing studieson the their paleoecology and paleobiology

CONDICIONANTE ETOLÓGICO NA TAFONOMIA DE UBERABASUCHUS TERRIFICUS (CROCODYLIFORMES, PEIROSAURIDAE) DA BACIA BAURU (CRETÁCEO SUPERIOR)

Uberabasuchus terrificus Carvalho, Ribeiro & Avilla, 2004 is a Crocodyliformes Peirosauridae from of the Serra da Galga Member – Marília Formation (Maastrichtian-Campanian) of Bauru Basin. The holotype of Uberabasuchus is remarkable for the preservation and articulation of its cranial and post-cranial elements. The preservation of Uberabasuchus specimen differs from the other fossils found at the same outcrop where it was discovered. This fact allows inferring a taphonomic history of Uberabasuchus distinct from the assembly of the same locality. It is observed in extant Crocodyliformes a burrowing behavior near water bodies, followed by a voluntary burial, as a reaction to stressed environmental conditions, as droughts or extreme temperatures. The preferential preservation of Crocodyliformes could result from their ability to build habitations and being (voluntarily) buried before death. The presented data indicates this potential ethological component in the taphonomic history of Uberabasuchus terrificus.Uberabasuchus terrificus Carvalho, Ribeiro & Avilla, 2004 é um Crocodyliformes Peirosauridae proveniente das proximidades de Peirópolis, Minas Gerais, de rochas do Membro Serra da Galga da Formação Marília (Maastrichtiano-Campaniano) da Bacia Bauru. O holótipo de Uberabasuchus é notável por sua preservação e a articulação dos elementos cranianos e pós-cranianos. A preservação e articulação do espécime de Uberabasuchus estão em dissonância com os demais fósseis do mesmo afloramento onde foi encontrado. Partindo deste fato isolado, é possível inferir para o fóssil de Uberabasuchus uma história tafonômica diferenciada da assembléia encontrada na mesma localidade e nível estratigráfico. É observado em Crocodyliformes recentes o comportamento de escavar rasas depressões próximas ou no leito de corpos aquosos, e posteriormente um soterramento voluntário e ativo, como reação à condições ambientais estressantes, como secas e temperaturas extremas. A preservação preferencial dos Crocodyliformes poderia ser devida à capacidade destes de construírem habitações e serem soterrados (voluntariamente) antes da morte ou soterramento final. Os dados apresentados vêm apontar este potencial modificador etológico ao histórico tafonômico de Uberabasuchus terrificus

Falanges ungueais de crocodilomorfos da Bacia Bauru (Cretáceo Superior, Brasil)

The ungual phalanxes of recent crocodylomorphs are modified into queratin covered claws. They are conical, ventrally curved with a sharp distal end. They are used during locomotion, digging and female sizing on copula. Nevertheless, fossil crocodylomorphs claws present a wider morphological and functional diversity. It was analysed fossil claws from the Late Cretaceous rocks of Adamantina (General Salgado County) and Marília (Uberaba County) Formations of the Bauru Basin. The claws found in the Adamantina Formation were associated with skeletal remains of a baurusuchid. They are laterally compressed, more ventrally curved and stronger than those of recent crocodylomorphs. They also present, at their base, many furrows related to muscle attachment. The claws found in the Marília Formation were associated to the remains of a peirosaurid. They show a great lateral compression and a blade-like ventral edge. They also present a slight ventral curvature and strong furrows in their base for muscle attachment. The morphological data obtained from these claws allow the investigation of the autoecology of these Cretaceous crocodylomorphs.As falanges ungueais dos crocodilomorfos atuais são modificadas em garras cônicas, curvas ventralmente, com extremidade distal pontiaguda, recoberta por camadas de queratina. São utilizadas comoauxílio para tração durante o deslocamento, escavação e apreensão da fêmea durante a cópula. Entretanto, os crocodilomorfos fósseis apresentam maior diversidade morfológica e possivelmente funcional destas garras. Foram analisadas garras fósseis oriundas de rochas do Cretáceo Superior da Bacia Bauru, nas formações Adamantina (Município de General Salgado) e Marília (Município de Uberaba). As garras encontradas na Formação Adamantina estavam associadas a restos esqueléticos de um baurussuquídeo. Apresentam achatamento lateral, curvatura ventral intensa e robustez maior que a observada entre crocodilomorfos recentes, e várias estrias relacionadas aos ligamentos musculares na base da garra. As garras encontradas na Formação Marília estão associadas aos ossos de um peirossaurídeo. São robustas e intensamente comprimidas lateralmente; sua face ventral é comprimida e possui aspecto laminado. Apresentam pequena curvatura ventral e fortes estrias de fixação muscular em sua base. As características morfológicas destas garras podem auxiliar na investigação dos hábitos de vida destes crocodilomorfos cretácicos

Mariliasuchus robustus, um novo Crocodylomorpha (Mesoeucrocodylia) da Bacia Bauru, Brasil

Herein is described a new species of a Crocodylomorpha Mesoeucrcodylia belonging to the genus Mariliasuchus from the Adamantina Formation (Upper Cretaceous, Turonian-Santonian), Bauru Basin, Brazil. The diagnostic features of the new species of Mariliasuchus are related to increased stoutness of the skull, wich is high, short and posteriorlly wide; the posterior region of the skull is almost as high as wide. The rostrum is straight, high, and rectangular in cross-section, with a convex dorsal surface, bearing no signs of a antorbital fenestrae. The orbits are large and laterally positioned in the skull. The external nares are forward oriented. The dentition presents pointed anterior teeth (incisiform), a hypertrophied caniniform and a low and globular post-caniniform teeth. The mandible is robust and display a strong vertical bending in its anterior and posterior ends.É descrita uma nova espécie de Crocodylomorpha Mesoeucrocodylia pertencente ao gênero Mariliasuchus, proveniente da Formação Adamantina (Cretáceo Superior, Turoniano-Santoniano), Bacia Bauru, município de Marília, Estado de São Paulo. As características diagnósticas da nova espécie de Mariliasuchus estão relacionadas à robustez acentuada do crânio, que apresenta-se alto, curto e largo posteriormente; na porção posterior do crânio a altura e comprimento são quase equivalentes. O rostro é estreito, alto e de forma retangular em seção transversal, com a face dorsal abaulada, não havendo sinais da presença de fenestra antero-orbital. As órbitas são grandes e ocupam uma posição lateral em relação ao crânio. As aberturas das narinas externas são orientadas frontalmente. A dentição é morfologicamente diferenciada, com dentes anteriores (incisiformes) pontiagudos, um caniniforme hipertrofiado e dentes pós-caniniformes de forma globosa. A mandíbula é robusta, apresentando um forte arqueamento vertical em sua porção anterior e posterior

Descrição do pós-crânio de Uberabasuchus terrificus Carvalho, Ribeiro e Avilla 2004 (Crocodyliformes, Peirosauridae) do Cretáceo Superior da bacia Bauru: inferências morfofuncionais e paleoautoecológicas

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Estágios de desenvolvimento de Mariliasuchus amarali, Crocodyliformes Mesoeucrocodylia da Formação Adamantina, Cretáceo Superior da Bacia Bauru, Brasil

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

Montealtosuchus arrudacamposi Carvalho, Vasconcellos & Tavares, 2007, gen. nov.

Montealtosuchus arrudacamposi gen. nov. et sp. nov. (Plate 1, 2) Etymology: The species name, arrudacamposi, is in honor of Antonio Celso de Arruda Campos, eminent Brazilian paleontologist and professor. Holotype: MPMA- 16 -0007-04 (Museu de Paleontologia de Monte de Alto). Skull, mandible and almost complete axial and appendicular skeleton, and articulated dorsal and ventral exoskeleton (osteoderms). Locality: 14 km of Monte Alto, near the border between Monte Alto and Taiaçu counties, São Paulo State, Southeast of Brazil. Stratigraphic context: Bauru Basin, Adamantina Formation, Upper Cretaceous (Turonian-Santonian). PLATE 1. Holotype of Montealtosuchus arrudacamposi gen. nov. et sp. nov. (MPMA- 16 -0007-04) in 1 dorsal view of skull and mandible; 2 lateral view of the skull; 3 lateral view of mandible; 4 palatal view; 5 dorsal view of mandible; 6 occipital view. Diagnosis (skull): Snout moderately narrow, tubular in cross-section. Skull triangular in dorsal view. Anterior nasal process at the tip of snout, hanging over the external naris. Continuously sloping surface connecting the rostrum and skull table. A small slit-shaped notch for the 4 th mandibular tooth at the contact between maxilla and premaxilla. Five premaxillary conical teeth progressively increase in size posteriorly, all evenly spaced. Wedge-like maxillary process of the premaxilla present. Foramen incisivum with maxillary marginal contribution. Fourteen maxillary teeth in sinuous outline, with moderate heterodonty, displaying anterior sharp conical teeth and posterior low, laterally compressed globular teeth. Anterolateral external nares in vertical position. Nasals participating in a non-septate external nares. Orbits subsquare. Antorbital fenestrae present. Two triangular supraorbitals bordering dorsally the orbit. Postorbital bar ascending from the mesial border of the jugal. Supratemporal fenestrae elliptical, smaller than orbits, and set in a non-sculptured depression, bordered by the parietal, postorbital, squamosal and small contribution of the frontal. Supratemporal with minimal participation in skull table. Quadratojugal participates with the quadrate in skull-mandible articulation. Deep, square choanae, evenly composed by palatines and pterygoids. Palatine fenestrae elliptical, bordered by maxillae, palatines, ectopterygoids and pterygoids. Basioccipitals inclined toward the palatal surface. Exoccipitals wide and bend anteriorly and half of its height. Eustachian foramina closely disposed in “v” pattern, in the palatal view. Splenials participating in 1 / 3 of the symphysis. Symphysis extending to the 10 th tooth. Mandible arched upward at anterior and posterior ends. Articular presents deep concave articular surface, with contribution from the surangular. Retroarticular process paddle-shaped and inclined dorsally and mesially. Mandibular fenestrae elliptical, aligned with the laterotemporal fenestrae. Eighteen dentary teeth show two morphotypes: anterior ones conical and sharp, with hypertrophied 4 th tooth; posterior teeth globular, low, and laterally compressed. All premaxillary, except the first, maxillary and dentary teeth bear constricted basal crown and fine serrated carinae.Published as part of Carvalho, Ismar De Souza, Vasconcellos, Felipe Mesquita De & Tavares, Sandra Apare- Cida Simionato, 2007, Montealtosuchus arrudacamposi, a new peirosaurid crocodile (Mesoeucrocodylia) from the Late Cretaceous Adamantina Formation of Brazil, pp. 35-46 in Zootaxa 1607 on page 38, DOI: 10.5281/zenodo.17883

Montealtosuchus Carvalho, Vasconcellos & Tavares, 2007, gen. nov.

Montealtosuchus gen. nov. Etymology: The generic name Montealtosuchus, is derived from Monte Alto County Diagnosis: The same as for speciesPublished as part of Carvalho, Ismar De Souza, Vasconcellos, Felipe Mesquita De & Tavares, Sandra Apare- Cida Simionato, 2007, Montealtosuchus arrudacamposi, a new peirosaurid crocodile (Mesoeucrocodylia) from the Late Cretaceous Adamantina Formation of Brazil, pp. 35-46 in Zootaxa 1607 on page 37, DOI: 10.5281/zenodo.17883

FIGURE 1 in Montealtosuchus arrudacamposi, a new peirosaurid crocodile (Mesoeucrocodylia) from the Late Cretaceous Adamantina Formation of Brazil

FIGURE 1. Bauru Basin (modified from Fernandes & Coimbra, 1996