Leonardo dos Santos Avilla

Uberabasuchus terrificus sp. nov., a New Crocodylomorpha from the Bauru Basin (Upper Cretaceous), Brazil

Abstract A new fairly complete and articulated skull of a Peirosauridae crocodylomorph from Bauru Basin (Late Cretaceous), Brazil, is described. The fossil is from a level of clayish sandstone within Serra do Veadinho sequence, Peiropolis, Uberaba County, Minas Gerais State. The sedimentary strata of Serra do Veadinho belong to the Marilia Formation (Serra da Galga Member), Bauru Group, considered to be Campanian-Maastrichtian in age. The species -Uberabasuchus terrificus sp. nov. - is a peirosaurid with moderately narrow snout, large round orbits protected by supraorbital bones of triangular shape and an antorbital fenestra bounded posteriorly by a deep groove. This fossil resembles Peirosaurus tormini Price, 1955 in the size pattern of premaxillary teeth and by showing a similar wedge-like maxillary process in the premaxilla. It also shares some morphological features with the other species of the Peirosauridae, namely the crocodylomorph Lomasuchus palpebrosus Gasparini, Chiappe and Fernandez, 1991 from Argentina. Their common features comprise a moderately narrow snout and the deep lateral groove at the premaxilla and maxilla articulation for the reception of a large mandibular tooth. However, the nasal participates in the external nares and does not divide the nasal aperture, producing a “beak-like” structure at the extremity of the snout which is unique among peirosaurids. The stratigraphic setting suggests that the specimen was buried when a flash flood overflowed the shallow channels of a braided fluvial system. Parsimony analysis of 183 morphological characters is performed for 23 crocodylomorphs. Analysis of the morphological data matrix resulted in three most parsimonious trees (374 steps, CI = 0.679; RI = 0.826). The new species is closely related to Mahajangasuchus and both, in addition to Peirosaurus and Lomasuchus, compose the Peirosauridae.

BITE MARKS ON A CROCODYLOMORPH FROM THE UPPER CRETACEOUS OF BRAZIL: EVIDENCE OF SOCIAL BEHAVIOR?

Fossil bones that bear marks from activities of other organisms can provide insight into the ecology, behavior, and functional morphology of the taxa that produced them (Evans, 1983; Bell and Martin, 1995; Erickson and Olson, 1996; Tanke and Currie, 1998). However, most studies on such marks concern invertebrate bioturbation or bioerosion (Carvalho and Fernandes, 2000). Studies on bone marks produced by vertebrates are less common (Abel, 1922; Buffetaut, 1983; Evans, 1983; Fiorillo, 1991; Erickson and Olson, 1996; Tanke and Currie, 1998; Frey et al., 2002). Bite marks are usually interpreted as the result of predator or scavenger habit, although determination between these two habits is controversial, at best. In other words, it is uncertain if the teeth marks presented on a fossil are record of the use of a lethal “weapon” or the record of a post-mortem alimentary association. In the austral spring of 2001, the Laboratório de Macrofósseis/IGEO Universidade Federal do Rio de Janeiro organized a paleontological expedition to some fossil localities at the Adamatina Formation in the state of São Paulo. The Adamantina Formation is a very fossiliferous unit of the Bauru Basin, Brazil. The most important fossil localities of this basin are located in the states of São Paulo, Mato Grosso, and Minas Gerais (Kellner and Campos, 2000), where a rich fauna of fishes, amphibians, crocodiles, lizards, turtles, dinosaurs and a mammal have been recovered (Bertini et al., 1993). The Adamantina Formation is dominated by reddish clays and sands of fluvial-lacustrine origin, deposited during times of warm and humid climates (Suguio and Barcelos, 1983). Judging from its vertebrate fossil contents, the Adamantina deposits were likely deposited sometime between the Santonian and Maastrichtian (Fernandes and Coimbra, 1996). The 2001 expedition produced a collection of ichnofossils and fossil remains including, mollusks, fishes, turtles, crocodylomorphs, and dinosaurs. Among these fossils, we found a tail of an adult crocodylomorph (Fig. 1) on which we found evidence of bite injuries. In the present paper, we describe those marks and argue that members of the same species made those injuries, probably in intermale combat.

Diversity and paleoenviromental significance of Brazilian fossil Galictis (Carnivora: Mustelidae)

The evolutionary history of the genus Galictis in South America probably begins after the Great American Biotic Interchange. Two species are recognised: Galictis vittata and Galictis cuja. The latter are more frequently found in open areas in southern South America and the first occurs in humid forests from northern South America to Central America. Apparently, they do not occur in sympatry. Both are differentiate by the presence of a metaconid in the first inferior molar of G. vittata and for its bigger size when compared to G. cuja. The fossil record of Galictis is scarce, G. cuja is known by few specimens from Argentina, Chile and Brazil; G. vittata have only one record from Southern Brazil. The specimens related to this record were collected by Peter Lund and are housed at the Statens Naturhistoriske Museum. However, the specimens published by Lund are not fossils. Thus, it is presented here other unpublished specimens collected by Lund and housed at the same museum that we recognise as the first G. vittata fossils. Additionally, it is described here the first fossil record for G. cuja from the late Pleistocene of Brazil – an almost complete mandible recovered from sedimentary deposits from Central Brazil.

Redescrição de Litomosoides brasiliensis Almeida, 1936 (Nematoda: Filariidae) Parasito de Anoura caudifera (Chiroptera: Phyllostomidae)

The study of the surface topography added details regarding the disposition of male caudal papillae, spicules and area rugosa apart from vulva and oral aperture. The occurrence of this nematode in the state of Amapa represents a new geographical distribution.