We report a new pleurodiran turtle from the Barremian Morro do Chaves Formation, Sergipe-Alagoas Basin, Brazil. We tested the phylogenetic position of Atolchelys lepida gen. et sp. nov. by including it in a comprehensive cladistic analysis of pleurodires. The new species is a basal member of Bothremydidae and simultaneously the oldest unambiguous crown Pleurodira. The biogeographic and chronostratigraphic significance of the finding has implications for the calibration of molecular clocks studies by pushing back the minimum age of crown Pleurodira by more than 12 Ma (ca 125 Ma). The reanalysis of Pelomedusoides relationships provides evidence that the early evolution and relationships among the main lineages of side-necked turtles can be explained, at least partially, by a sequence of vicariance events.

Enchodontoidei are extinct marine teleost fishes with a long temporal range and a wide geographic distribution. As there has been no comprehensive phylogenetic study of this taxon, we performed a parsimony analysis using a data matrix with 87 characters, 31 terminal taxa for ingroup, and three taxa for outgroup. The analysis produced 93 equally parsimonious trees (

This paper describes a possible fossil egg proceeding from the Bauru Group, Late Cretaceous of Paraná Basin, Brazil. External morphology, dimensions, texture and shell ornamentation examined under electron microscopy show close resemblance to the Recent podocnemidid chelonian eggs. Association with bony material in the outcrop suggests that it is related to a species of Podocnemis. Computerized tomography reveals a high density outer region corresponding to the shell component layers, and successive layers with decreasing density towards the nucleus. An area of high density in the central region may represent remains of an embryo.

Brazilichthys macrognathus is the only named actinopterygian from the Permain (Cisuralian) Pedra de Fogo Formation of northeastern Brazil, where it is represented by a single three-dimensionally preserved but incompletely described skull of unclear systematic placement. We used X-ray computed microtomography (µ-CT) to better document its anatomy and phylogenetic affinities. µ-CT reveals parts of the internal skeleton. We correct errors in original description, including the number of infraorbital bones and the misidentification of the dermosphenotic as sclerotic ossifications. These reinterpretations of external anatomy are joined by new data on internal structure, including the palate, parasphenoid, and branchial and hyoid arches. A maximum parsimony analysis of anatomical data resolves Brazilichthys as a stem actinopterygian, crownward of all Devonian species. This placement is supported by the absence of a dermosphenotic posterior ramus and the presence of opercular process of the hyomandibula. A similar placement is suggested by a Bayesian analysis of this same dataset, although relationships throughout the tree are less resolved. Our results reject previous interpretations of Brazilichthys as a relative of Birgeriidae, a Triassic group consistently placed within the actinopterygian crown. Although Acrolepis is too poorly known to be included in our analysis, we also reject a close relationship between this taxon and Brazilichthys, as their only shared similarities appear to be broadly distributed among early actinopterygians.

Brazilichthys macrognathus is the only named actinopterygian from the Permain (Cisuralian) Pedra de Fogo Formation of northeastern Brazil, where it is represented by a single three-dimensionally preserved but incompletely described skull of unclear systematic placement. We used X-ray computed microtomography (µ-CT) to better document its anatomy and phylogenetic affinities. µ-CT reveals parts of the internal skeleton. We correct errors in original description, including the number of infraorbital bones and the misidentification of the dermosphenotic as sclerotic ossifications. These reinterpretations of external anatomy are joined by new data on internal structure, including the palate, parasphenoid, and branchial and hyoid arches. A maximum parsimony analysis of anatomical data resolves Brazilichthys as a stem actinopterygian, crownward of all Devonian species. This placement is supported by the absence of a dermosphenotic posterior ramus and the presence of opercular process of the hyomandibula. A similar placement is suggested by a Bayesian analysis of this same dataset, although relationships throughout the tree are less resolved. Our results reject previous interpretations of Brazilichthys as a relative of Birgeriidae, a Triassic group consistently placed within the actinopterygian crown. Although Acrolepis is too poorly known to be included in our analysis, we also reject a close relationship between this taxon and Brazilichthys, as their only shared similarities appear to be broadly distributed among early actinopterygians. 1969) or detailed descriptions of only single constituent taxa (e.g. Ebenaqua from Rangal Coal Measures of Blackwater, Australia; Campbell and Phuoc, 1983). Brazilian deposits yield the vast majority of Permo-Carboniferous actinopterygians known from South America (Cione et al., 2010), with only a handful of examples known from elsewhere, mostly based on poorly preserved specimens (e.g. Beltan, 1978; this material is now considered lost, pers. comm. Piñeiro, G., April 18, 2017). Despite the relative neglect of the South American record of Paleozoic fishes, sporadic research efforts reveal substantial assortment of Permian actinopterygians from Brazil. These span the Permian and overwhelmingly derive from deposits in the Paraná Basin of southern Brazil: the Rio do Sul (Cisuralian in age and yielding Elonichthys gondwanus; Richter et al., 1985), Campo Mourão (Cisuralian in age and yielding Roslerichthys riomafrensis and Santosichthys mafrensis; Hamel, 2005; Malabarba, 1988), Rio Bonito Formation (Guadalupian-Lopingian in age yielding Tholonosteon santacatarinae; Richter et al., 1985) Rio do Rasto (Guadalupian-Lopingian in age and yielding Rubidus pascoalensis and Paranaichthys longianalis; Richter, 2002; Dias, 2012), and Corumbataí (Lopingian in age and yeilding Tholonotus brasiliensis and Angatubichthys mendesi; Dunkle and Schaeffer, 1956;Figueiredo and Carvalho, 2004) formations. By contrast, Brazilichthys macrognathus is the only Permian actinopterygian known from the Parnaíba Basin in...