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A paleoparasitological investigation was carried out on Crocodyliformes coprolites discovered in the Municipality of Santo Anastacio, in the southwestern region of the State of Sao Paulo. Individual samples were extracted from the surface and internal portion of each coprolite which revealed the presence of thick-shelled parasite eggs in three of them. The morphological characteristics of the specimens, i.e., rounded or oval shape, thick-shelled with mammillated surface, as well as their size, suggest that these eggs belong to the superfamily Ascaridoidea, which are gastrointestinal parasite nematodes of vertebrates, popularly known as “roundworms”. This is the first record of Ascaridoidea eggs discovered in Crocodyliformes hosts from the Upper Cretaceous of Brazil.

Made available in DSpace on 2019-10-06T16:49:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01. Added 1 bitstream(s) on 2019-10-09T18:35:38Z : No. of bitstreams: 1 S0001-37652019000400508.pdf: 2788820 bytes, checksum: 62cf24a2ab93abbe5b24a0dc6073b2e3 (MD5) This study presents the oldest record of Acanthocephala parasite eggs in coprolites preliminary assigned to Crocodyliformes, recovered in the region of Santo Anastácio Municipality, Southwestern São Paulo State. For this, a paleoparasitological investigation was carried out on 53 mineralized coprolites ( complete or fragmented), with round shape or cylindrical shape of rounded or pointed ends, 0.2 - 3.9 cm in length x 0.1 - 2.4 cm in diameter, 3.7 grams in weight, and absence of food remains. Individual samples of the surface and internal portions of each coprolite were extracted by electric drill, dissociated with Cloridic Acid 10% solution, washed with Distilled Water, and filtered in granulometric screen Mesh / Tyler 325. After laboratory processing, the sediments retained on the granulometric screen was studied with Glycerin under optical microscopy, and the presence of four Acanthocephala eggs could be observed in sample of only one of these ichnofossils. All specimens were well preserved and showed 72.5 - 85 µm in length x 27.5 - 50 µm in width, elliptical shape, three concentric and thick shells, and embryos in their interior. This study inaugurates investigations and knowledge about Paleoparasitology in Crocodyliformes coprolites from the Bauru Group, Upper Cretaceous from the Paraná Basin. Núcleo de Evolução e Paleobiologia de Vertebrados, Departamento de Geologia Aplicada, Instituto de Geociências e Ciências Exatas, UNESP, Campus Rio Claro. Av. 24 A, 1515, 13506-900 Rio Claro, SP, Brazil

Made available in DSpace on 2019-10-04T12:37:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The Bauru Group has three crocodyliform taxa: Itasuchus, Pepesuchus and Barreirosuchus. Within these taxa, the skulls of Itasuchus jesuinoi and Barreirosuchus franciscoi are fragmentary and have no described postcranial material, hindering the comparison with other specimens with known taxonomic positions. Thus, the taxonomic placement of I. jesuinoi and B. franciscoi remains unsolved. Additionally, although the Marilia Formation has been dated to the Maastrichtian Age, the chronology of the Adamantina Formation is up for debate. New material found in the Adamantina Formation, referred to Pepesuchus, is described. Phylogenetic analysis returned a supported clade composed of Itasuchus, Pepesuchus and Barreirosuchus, here named Pepesuchinae. Pepesuchinae is a sister clade to Peirosaurinae, a clade grouping Peirosaurus, Uberabasuchus, Montealtosuchus and Hamadasuchus. The calibrated cladogram dates the origin of the Bauru Group to the early Santonian, and the morphological similarity between the taxa from the Adamantina and Marilia formations makes it possible to infer a Campanian-Maastrichtian age for the Adamantina Formation. Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, Posgrad Geol Reg, Nucleo Evolucao & Paleobiol Vertebrados, Campus Rio Claro,Av 24 A-1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, Posgrad Geol Reg, Nucleo Evolucao & Paleobiol Vertebrados, Campus Rio Claro,Av 24 A-1515, BR-13506900 Rio Claro, SP, Brazil CNPq: 141177/2011-0

Made available in DSpace on 2019-10-06T16:36:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-10-01 Two new ascaridoid species, Bauruascaris cretacicus n. gen. et n. sp., and Bauruascaris adamantinensis n. gen. et n. sp., are described based on the fossils of eggs preserved in 80–70 million year old phosphatized coprolites of Crocodyliformes, chronologically assigned to the Upper Cretaceous (Campanian/Maastrichtian age), collected from sedimentary rocks of the Bauru Group, Adamantina Formation in the municipality of Santo Anastácio, in the southwestern region of the state of São Paulo, Brazil, South America. This paper describes the oldest ascaridoid species ever recorded in Crocodylomorpha. Hence, this article contributes to the body of knowledge about the evolutionary history of this nematode group. It also offers a clue about the composition of the parasite fauna of these reptiles from the Late Cretaceous, which is still unknown despite numerous studies about various aspects of their biology and the pioneering paleoparasitological analysis of animal coprolites by South American researchers. Núcleo de Evolução e Paleobiologia de Vertebrados Departamento de Geologia Aplicada Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista UNESP, Campus Rio Claro, Avenida 24 A/1515, Jardim Bela Vista Núcleo de Evolução e Paleobiologia de Vertebrados Departamento de Geologia Aplicada Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista UNESP, Campus Rio Claro, Avenida 24 A/1515, Jardim Bela Vista

The Adamantina Formation (Bauru Group), between Lucelia and Irapuru municipalities (northwestern Sao Paulo State, southeastern Brazil), has been in the last years a very important area for collecting Upper Cretaceous fossil vertebrates. So far, the main groups recovered include Testudines, Crocodyliformes and Dinosauria (Theropoda and Titanosauria). The fossil material is usually disarticulated and fragmented and was collected from very fine-grained sandstones, with muddy matrix and cross-stratification and lamination. Testudines are represented by fragments of carapaces and plastrons. Crocodyliformes are composed only of fragmented osteological remains and isolated teeth. Maniraptora is especially represented by isolated teeth, allowing the identification of the Dromaeosaurinae, Velociraptorinae and Troodontidae clades, in addition to some probable endemic groups. Titanosauria is the most representative and abundant group in these fossil localities, however materials are mainly fragments of ribs and some appendicular bones, without diagnostic osteological elements, like caudal vertebrae. The lithological characteristics of the outcrops suggest a paleoenvironment of braided rivers, in an arid climate, with few vegetation cover.

Among taxons of Crocodyliformes from the Bauru Group (Late Cretaceous), a large number of morphotypes, including cranial and post-cranial materials, have been described associated with Baurusuchus pachecoi. However, the lack of ontogenetic studies, similar to what has been done with Mariliasuchus amarali, has led to the allocation of new genera and species to the few complete skulls found. The present contribution provides the description of a juvenile specimen of Baurusuchidae, housed in the collection of the "Museu de Ciencias da Terra", Rio de Janeiro, under the number MCT 1724 - R. It is composed of rostrum and mandible, associated and in occlusion, with the left side better preserved than the right one, with extremely reduced ziphodont dentition. The fossil is 125.3 mm in preserved length from the anterior edge of the premaxilla to the posterior end of the dentary; 117.5 mm in preserved length from premaxilla to palatines; and 51.4 mm in lateral height. Among the ontogenetic aspects observed are faint ornamentation, consisting of very separated, large vermiform grooves, a straighter maxillary ventral line, dentary slightly dorsally inclined, mandibular symphysis less vertical than in other Baurusuchidae of large size. The greater part of the diagnostic characters of Baurusuchus pachecoi were identified in MCT 1724 - R: high rostrum and compressed lateral, and ziphodont dentition with strong dental reduction, culminating in four premaxillary and five maxillary teeth. In conclusion, as the morphotype cannot be separated morphologically from the type species of the genus and because it has been found in outcrops of the Adamantina Formation, it is possible to identify it as a juvenile Baurusuchus cf. pachecoi. Changes which can be observed gradually from smaller to larger morphotypes, thus being of ontogenetic nature include: an increase in skull ornamentation; the median/posterior portion of the ventral edge of the maxilla passing from straight to concave; and the verticalization of the mandibular symphysis line to close to 45o.