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An isolated caudal vertebral centrum of a theropod dinosaur was discovered in the Bauru Basin (Late Cretaceous) of Brazil, in the Maastrichtian São José do Rio Preto Formation. The vertebral centrum has pneumatic features that are similar to those in the megaraptoran theropods Aerosteon, Megaraptor, and Orkoraptor. For example, all these taxa share with the caudal centrum here described the presence of true pleurocoels or pneumatic foramina, immersed within a depression or fossa. Thus, the specimen is considered the first record of Megaraptora in Brazil. The present analysis provides new information on the vertebral caudal anatomy of this clade of bizarre Cretaceous theropods.  相似文献   

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First cyclotide from Hybanthus (Violaceae)   总被引:1,自引:0,他引:1  
Hypa A, a novel macrocyclic polypeptide containing 30 amino acid residues, has been isolated from the n-butanol extract of the Argentine plant Hybanthus parviflorus. The sequence, cyclo-(SCVYIPCTITALLGCSCKNKVCYNGIPCAE), was determined by automated Edman degradation, quantitative amino acid analysis and nanospray MS/MS(2). Three intramolecular disulfide bridges stabilize the cyclic peptide backbone of hypa A. Using these structural features to classify the peptide as a cyclotide, we extended the distribution of that substance class to a new genus, and now propose a uniform nomenclature for cyclotides.  相似文献   

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Lasasaurus beltanae nov. gen. nov. sp., a new procolophonid (Reptilia, Parareptilia) from the Lower Triassic of Madagascar, is represented by a single partial skeleton preserved in a ferro-calcareous nodule from the Middle Sakamena Formation, in the North of the island. This new taxon is unique in possessing peculiar, fine and dendritic crests running along the posterolateral side of the squamosal, widely spaced maxillary teeth, subparallel mesiodistal ridges connecting maxillary teeth to the tooth row, and a strongly acute anterior margin of the copula (hyoid bone). This well-preserved specimen belongs to a juvenile individual. The inclusion of L. beltanae nov. gen. nov. sp. in a phylogenetic analysis suggests that it is close to Theledectinae, Procolophoninae, and Leptopleurinae, though their respective relationships are uncertain. This specimen is the first procolophonid described from Madagascar and represents a minor terrestrial component of a coastal vertebrate assemblage dominated by amphibious to fully-aquatic taxa.  相似文献   

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One specimen of the obtuse barracuda Sphyraena chrysotaenia is recorded for the first time from the Adriatic Sea.  相似文献   

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Previously known from Brazil, North Argentina, Paraguay, and Bolivia, Diversitermes diversimiles (Silvestri, 1901) is cited for the first time from French Guiana, on the basis of the soldier and worker castes. The digestive tube of its worker is photographied for the first time.  相似文献   

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<正>Dear Editor,e family Ranidae is one of the largest and most families of amphibians (Che et al., 2007), with 64 recognized genera and429 species (Frost, 2022). However, the systematics and natural history of some ranid groups have not been well-studied. One such example is the taxonomic relationship between Sylvirana,H ylarana and other closely-related taxa (Che et al., 2007; Pyron and Wiens, 2011; Oliver et al., 2015). China has a large diversity of ranid frogs,with 146 speciesbelonging...  相似文献   

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The single extant species of the anuran genus Latonia lives in Israel, but in the fossil record the genus is known mainly from Europe, spanning from the Oligocene to the early Pleistocene. Here we describe new remains of Latonia from the early to late Miocene of the Vallès-Penedès Basin (NE Iberian Peninsula), coming from the following localities: Sant Mamet (MN4), Sant Quirze and Trinxera del Ferrocarril (MN7+8), and Castell de Barberà, Can Poncic 1 and Can Llobateres 1 (MN9). Fossils from the late Aragonian and early Vallesian are attributed to Latonia gigantea mainly because of the morphology of the ornamentation that covers the maxillae. In turn, an ilium from Sant Mamet is not diagnostic at the specific level and is assigned only to the genus Latonia. The newly reported remains represent the first record of L. gigantea in the Iberian Peninsula, where Latonia was previously known by a single report of Latonia cf. ragei from Navarrete del Río (MN2) and remains from other localities unassigned to species. Moreover, the Vallès-Penedès remains represent one of the southernmost records of the species known thus far. The presence of Latonia in these localities confirms the humid and warm environment suggested by the recorded mammal fauna.  相似文献   

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Despite uncontested evidence for fossils belonging to the early hominin genus Australopithecus in East Africa from at least 4.2 million years ago (Ma), and from Chad by 3.5 Ma, thus far there has been no convincing evidence of Australopithecus, Paranthropus or early Homo from the western (Albertine) branch of the Rift Valley. Here we report the discovery of an isolated upper molar (#Ish25) from the Western Rift Valley site of Ishango in Central Africa in a derived context, overlying beds dated to between ca. 2.6 to 2.0 Ma. We used µCT imaging to compare its external and internal macro-morphology to upper molars of australopiths, and fossil and recent Homo. We show that the size and shape of the enamel-dentine junction (EDJ) surface discriminate between Plio-Pleistocene and post-Lower Pleistocene hominins, and that the Ishango molar clusters with australopiths and early Homo from East and southern Africa. A reassessment of the archaeological context of the specimen is consistent with the morphological evidence and suggest that early hominins were occupying this region by at least 2 Ma.  相似文献   

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Cenozoic bird tracks are known largely from North America, Europe, and the Middle East. There have been no reports of Cenozoic bird tracks from East Asia. This paper describes a series of two trackways produced by a galliform-like or gruiform-like bird from the Oligocene to Early Miocene of Tibet. The tracks are represented by tracings collected from a coal mine in Shigatse, Tibet, during the late 1970s. The tracks are comparable to Ornithoformipes and Pavoformipes and likely represent a medium-sized to large cursorial or flightless bird. In relation to modern bird tracks, the tracks bear a striking resemblance to those produced by the North American Wild Turkey (Meleagris gallopavo) except that M. gallopavo tracks often possess a small, elevated hallux impression. Due to the fact that these are tracings, however, a hallux may have been present and simply have been overlooked. The Shigatse trackways were, unfortunately, lost when the mine was closed and then backfilled during the 1980s, and there is little to no likelihood of recovery. Casts can be catalogued as holotype specimens but tracings cannot; however, all the original tracings have been donated to a public institution by their discoverer, Yimin Wu.  相似文献   

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