RESUMEN
Late Jurassic rhynchocephalians from the Solnhofen Archipelago have been known for almost two centuries. The number of specimens and taxa is constantly increasing, but little is known about the ontogeny of these animals. The well-documented marine taxon Pleurosaurus is one of such cases. With over 15 described (and many more undescribed) specimens, there were no unambiguous juveniles so far. Some authors have argued that Acrosaurus, another common component of the Solnhofen Archipelago herpetofauna, might represent an early ontogenetic stage of Pleurosaurus, but the lack of proper descriptions for this taxon makes this assignment tentative, at best. Here, we describe the first unambiguous post-hatchling juvenile of Pleurosaurus and tentatively attribute it to Pleurosaurus cf. P. ginsburgi. The new specimen comes from the Lower Tithonian of the Mörnsheim Formation, Germany. This specimen is small, disarticulated, and incomplete, but preserves several of its craniomandibular bones and presacral vertebrae. It shares with Pleurosaurus a set of diagnostic features, such as an elongated and triangular skull, a low anterior flange in its dentition, and an elongated axial skeleton. It can be identified as a juvenile due to the presence of an unworn dentition, well-spaced posteriormost dentary teeth, a large gap between the last teeth and the coronoid process of the dentary, and poorly ossified vertebrae with unfused neural arches. Acrosaurus shares many anatomical features with both this specimen and Pleurosaurus, which could indicate that the two genera are indeed synonyms. The early ontogenetic stage inferred for the new Pleurosaurus specimen argues for an even earlier ontogenetic placement for specimens referred to Acrosaurus, the latter possibly pertaining to hatchlings.
RESUMEN
Paleopathology, the study of diseases and injuries from the fossil record, allows for a unique view into the life of prehistoric animals. Pathologies have nowadays been described in nearly all groups of fossil vertebrates, especially dinosaurs. Despite the large number of skeletons, pathologies had never been reported in the sauropodomorph Plateosaurus trossingensis. Here we describe the first pathologies of Plateosaurus using two individuals with pathologies in the chevrons of the tail, from the Upper Triassic of Trossingen, SW Germany. The two specimens each contain three consecutive pathological chevrons. Our results show that the pathologies were caused by external trauma in one individual and potentially tendinous trauma in the other. Healing of the lesions allowed survival of both animals. Using additional pathological specimens found in other collections and from multiple localities, we observe that 14.8% of all individuals of Plateosaurus contain pathologies within their chevrons, suggesting it was a vulnerable bone.
Asunto(s)
Dinosaurios , Fósiles , Animales , Dinosaurios/anatomía & histología , Alemania , Paleopatología , Huesos/patología , Huesos/anatomía & histologíaRESUMEN
A new species, Parahephaestion mimicus sp. nov., is described. Two species are newly recorded for the Brazilian state of Minas Gerais: Sphalloeme costipennis Melzer, 1928 (Cerambycinae, Oemini) and Oreodera omissa Melzer, 1932 (Lamiinae, Acrocinini). Six species are new records for the RPPN Sanctuary of Caraa, (Brazil, Minas Gerais): Thalusia atrata (Melzer, 1918) (Cerambycinae, Rhopalophorini), Trachelissa pustulata (Audinet-Serville, 1834) (Cerambycinae, Trachyderini), Ateralphus dejeani (Lane, 1973) (Lamiinae, Acanthoderini), Phacellocera plumicornis (Klug, 1825) (Lamiinae, Anisocerini), Oncideres impluviata (Germar, 1823), and Psyllotoxus griseocinctus Thomson, 1868 (Lamiinae, Onciderini).
Asunto(s)
Escarabajos , Avispas , Animales , BrasilRESUMEN
The osteology, neuroanatomy, and musculature are known for most primary clades of turtles (i.e., "families"), but knowledge is still lacking for one particular clade, the Carettochelyidae. Carettochelyids are represented by only one living taxon, the pig-nosed turtle Carettochelys insculpta. Here, we use micro-computed tomography of osteological and contrast-enhanced stained specimens to describe the cranial osteology, neuroanatomy, circulatory system, and jaw musculature of Carettochelys insculpta. The jaw-related myology is described in detail for the first time for this taxon, including m. zygomaticomandibularis, a muscular unit only found in trionychians. We also document a unique arterial pattern for the internal carotid artery and its subordinate branches and provide an extensive list of osteological ontogenetic differences. The present work provides new insights into the craniomandibular anatomy of turtles and will allow a better understanding of the evolutionary history of the circulatory system of trionychians and intraspecific variation among turtles.
Asunto(s)
Cráneo , Tortugas , Animales , Tortugas/anatomía & histología , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Maxilares/anatomía & histología , Maxilares/diagnóstico por imagen , Microtomografía por Rayos X , OsteologíaRESUMEN
Dihammaphora Chevrolat (Arc Nat 1:50-54, 1859) is one of the most diverse genera of Rhopalophorini, with 46 species. It is characterized mainly by species with antennae short and subserrated, with 10 or 11 antennomeres, prothorax cylindrical, and elytra punctuated. In this study, two new species of Dihammaphora are described and illustrated, new records are provided to 11 species, and taxonomic notes are given to six species of the genus. We examined 55 specimens and identified 16 species of the genus Dihammaphora, including Dihammaphora aurea sp. nov. from Honduras, and Dihammaphora cruzi sp. nov. from Brazil. The number of species of Dihammaphora is increased to 48, two of them in Central America, resulting in seven species for this region. In Brazil, 24 species are now recognized, being the country with the largest number of species of the genus. This study shows that there is still a deficit of knowledge about the diversity and distribution of Dihammaphora.
Asunto(s)
Escarabajos , Animales , América Central , Geografía , BrasilRESUMEN
Metabolism, mainly driven by oxygen consumption, plays a key role in life, as it is one of the main ways to respond to extreme temperatures through internal processes. Theba pisana, a widespread Mediterranean land snail, is exposed to a wide range of ambient temperature. In this species the oxygen consumption was tested as a response variable by multiple regression modelling on the "explanatory" variables shell-free mass, temperature, and relative humidity. Our results show that the oxygen consumption of T. pisana can be well described (73.1%) by these three parameters. In the temperature range from 23 °C to 35 °C the oxygen consumption decreased with increasing temperature. Relative humidity, in the range of 67% to 100%, had the opposite effect: if it increases, oxygen consumption will increase as well. Metabolism is proportional to an individual's mass to the power of the allometric scaling exponent α, which is between 0.62 and 0.77 in the mentioned temperature range. CT scans of shells and gravimetry revealed the shell-free mass to be calculated by multiplying the shell diameter to the third power by 0.2105. Data were compared to metabolic scaling exponents for other snails reported in the literature.
RESUMEN
Abstract Information regarding species occurrence is fundamental to understanding biodiversity distribution. However, the biodiversity from the west of the state of Paraná has been historically less studied, especially amphibians and reptiles. For this reason, we present the first reptile list of species from the west of the state of Paraná and extend the current list of anurans for the municipality of Foz do Iguaçu. The species list was based on a systematic field study conducted at Refúgio Biológico Bela Vista (RBV) a conservation area within the Hydroelectric Power Itaipu Binacional. We integrated the species list with previous species observations available in the literature for the same place where our sampling was conducted. A total of 41 species of amphibians and reptiles are presented. All amphibians species found were recorded in the field; however, from the 22 species of reptiles recorded, three were historical records obtained before this study. Species were all classified as Least Concern and/or had stable populational status according to the IUCN. Sampling sufficiency was achieved for anurans but not for reptiles, probably due to low abundance of several snake species. The most abundant species of anuran was Dendropsophus nanus, from the Hylidae family, whereas Leptodactylus plaumanni and Scinax squalirostris were represented by only one individual each. The lizard Salvator merianae was the most abundant reptile, and seven species were represented by only one individual each. The most successful sampling method for adult anurans was active search in water bodies whereas most of reptile species were observed by accidental encounters and not through a systematic sampling method. We found that herpetofauna composition from RBV was similar to other communities from Paraná state that also occur within the Semideciduous Seasonal Forest. Finally, as additional information to the species list, we offer species identification keys and discuss the importance of Refúgio Biológico Bela Vista to harbor the anuran and reptile diversity of the region.
Resumo Informações sobre a ocorrência de espécies são fundamentais para a compreensão da distribuição da biodiversidade. Porém, a biodiversidade do oeste do Estado do Paraná tem sido historicamente menos estudada, especialmente a de anfíbios e répteis. Por esse motivo, apresentamos a primeira lista de espécies de répteis do oeste do Estado do Paraná e ampliamos a lista atual de anuros para o município de Foz do Iguaçu. A lista de espécies foi baseada em um estudo sistemático de campo realizado em uma área de conservação dentro da Usina Hidrelétrica Itaipu Binacional. Integramos a lista de espécies com observações de espécies anteriores disponíveis na literatura para o mesmo local onde nossa amostragem foi realizada. Um total de 41 espécies são apresentadas. Todas as espécies de anuros encontradas foram registradas em campo; entretanto, das 22 espécies de répteis registradas, três foram registros obtidos antes deste estudo. Todas as espécies foram classificadas como "Pouco Preocupante" e/ou tinham status de "População Estável" de acordo com a IUCN. A suficiência amostral foi alcançada para anuros, mas não para répteis, provavelmente devido à baixa abundância de diversas espécies de serpentes. A espécie de anuro mais abundante foi Dendropsophus nanus, da família Hylidae, enquanto Leptodactylus plaumanni e Scinax squalirostris foram representados por apenas um indivíduo cada. O lagarto Salvator merianae foi o réptil mais abundante, e sete espécies foram representadas por um indivíduo cada. O método de amostragem mais bem sucedido para anuros adultos foi a busca ativa em corpos d'água, enquanto a maioria das espécies de répteis foi observada por encontros acidentais e não através de um método de amostragem sistematizado. Descobrimos que a composição da herpetofauna do Refúgio Biológico Bela Vista foi semelhante à de outras comunidades do estado do Paraná que também ocorrem dentro da Floresta Estacional Semidecidual. Por fim, como informações adicionais à lista de espécies, oferecemos chaves de identificação das espécies e discutimos sobre a importância da área de Itaipu para abrigar a diversidade de anuros e répteis da região.