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1.
A jaw bone attributed to the mid-Cretaceous azhdarchid pterosaur Alanqa saharica Ibrahim et al., 2010 is described. The new specimen from the Kem Kem beds of south eastern Morocco is unusual for the presence of expanded rostral bones that protrude above the occlusal surface of the jaws. The function of this unusual osteological modification is uncertain, but it is considered likely that it served a role in food processing, or perhaps jaw stability. 相似文献
2.
Determining the relationships of mid-Late Cretaceous African taxa is central to understanding the timing and resultant palaeobiogeographical patterns of Gondwanan fragmentation. The early Late Cretaceous (Cenomanian) Kem Kem beds of southeastern Morocco preserve a diverse vertebrate fauna, including sauropod dinosaurs. Sauropod material includes the holotype of the rebbachisaurid diplodocoid Rebbachisaurus garasbae and fragmentary remains representing indeterminate titanosauriforms and rebbachisaurids. Here, we describe two new specimens from the Kem Kem beds. A dorsal neural arch with complex internal pneumaticity is tentatively attributed to a somphospondylan titanosauriform. A caudal vertebra possessing several rebbachisaurid synapomorphies is excavated by a large and pervasive lateral pneumatic foramen, a feature undocumented in other rebbachisaurids. However, caudal vertebrae are currently unknown for the sympatric R. garasbae, so this element could be referable to that taxon or a second, previously unknown, rebbachisaurid species. Interestingly, this new caudal vertebra displays a mosaic of features otherwise restricted to limaysaurine or nigersaurine rebbachisaurids, suggesting a placement basal to these clades, which is the position usually recovered for R. garasbae in phylogenetic analyses. A review of the mid-Cretaceous African sauropod fossil record removes the Cretaceous record of dicraeosaurids from Africa, restricting this clade to a single post-Jurassic occurrence in Argentina. All diagnostic sauropod remains can be attributed to titanosauriforms or rebbachisaurids. Whereas rebbachisaurids were seemingly restricted to northwestern Africa and disappeared post-Cenomanian, titanosauriforms were widespread across the African continent and survived until the latest Cretaceous. The development of the mid-Cretaceous Trans-Saharan Seaway might have acted as a dispersal barrier for rebbachisaurids and other vertebrate groups. In contrast, titanosauriforms might have been able to cross this barrier, but it is possible that they were also unable to disperse, and that northwestern African titanosauriforms were not closely related to taxa from the rest of the African continent. New materials and a better understanding of titanosaur interrelationships will be crucial in teasing these scenarios apart. 相似文献
3.
Roy E. Smith David M. Martill David M. Unwin Lorna Steel 《Proceedings of the Geologists' Association. Geologists' Association》2021,132(1):110-126
A re-examination of fossil material from the Late Cretaceous Cambridge Greensand Member (CGM) of the West Melbury Marly Chalk Formation revealed a number of new specimens of edentulous pterosaur jaw fragments previously identified as shark fin spines and fish jaws and accessioned under the epithet ‘cestraciontid finray’ and ‘jaws of fish’. These are now recognised as pterosaurian jaw tips and referred to Ornithostoma sedgwicki Seeley, 1891 and Azhdarchoidea indet. This material increases the diversity of edentulous pterosaurs from the CGM.The edentulous pterosaur Ornithostoma sedgwicki Seeley, 1891 from the Cretaceous Cambridge Greensand of eastern England is reviewed. The holotype specimen is confirmed as a fragment of a premaxilla/maxilla of a non-tapejarid azhdarchoid on account of the conspicuous curvature of the dorsal and occlusal margins posteriorly and the presence of small neural foramina on the lateral margins. Neural foramina are not seen on jaws of members of the Pteranodontia, a group to which O. sedgwicki was included previously. The referral of O. sedgwicki to Azhdarchoidea eliminates the single known Lower Cretaceous occurrence of Pteranodontidae, restricting the temporal range of this taxon to the Upper Cretaceous. Postcranial material referred to O. sedgwicki from the type horizon is regarded as indeterminate Pterosauria. 相似文献
4.
A New Rhamphorhynchid Pterosaur (Pterosauria) from the Middle Jurassic Tiaojishan Formation of Western Liaoning, China 总被引：1，自引：0，他引：1
A new Sordes-like pterosaur Jianchangopterus zhaoianus gen. et sp. nov. is erected based on a almost complete skeleton with skull preserved. It is characterized by the following characters: seven and six pairs of upper jaw and lower jaw teeth respectively; the development of a recess on maxilla; the evenness of the dental margin in lateral view; a distinct central ridge along dorsal surface of the mandibular symphysis; wing phalanx 4 with strongly curved shaft approximately 96% the length of the wing phalanx 1. The discovery of a Sordes-like pterosaur Jianchangopterus, and other taxa from the same formation indicates that pterosaurs reached great diversities during the Middle to Upper Jurassic period. 相似文献
5.
A new pterosaur, Microtuban altivolans gen. et sp. nov., is described from the Sannine Formation of northern Lebanon. The specimen is the first pterosaur from the Early Cenomanian (Late Cretaceous) locality of Hjoûla and is regarded as the most complete pterosaur fossil discovered from Africa. While postcranial characters indicate a possible relationship with members of the Thalassodromidae or Chaoyangopteridae, the specimen possesses an exceptionally short wing-finger phalanx 4, forming only 1.1% of the total length of the wing-finger. Its appearance along with an unnamed ornithocheiroid from the slightly younger locality of Hâqel suggests that a number of pterosaur taxa existed within the local area, perhaps living on exposed carbonate platforms. 相似文献
6.
Rico Stecher 《Swiss Journal of Geoscience》2008,101(1):185-201
A new basal non-pterodactyloid pterosaur, Raeticodactylus filisurensis gen. et sp. nov., is reported. It has been discovered in shallow marine sediments from the Upper Triassic of the lowest Kössen beds (late Norian/early Rhaetian boundary) in the central Austroalpine of Canton Grisons (Switzerland). The disarticulated specimen is comprised of an almost complete skull and a partial postcranial skeleton. A high and thin bony, sagittal cranial crest characterizes the anterodorsal region of the skull. The large mandible, with an additional keel-like expansion at the front, partly matches the enlarged sagittal cranial crest. A direct and close relationship to Austriadactylus cristatus, the only known Triassic pterosaur with a bony cranial crest so far, cannot be established. The teeth of the premaxilla are monocuspid and exhibit very strongly bowed enamel wrinkles on the lingual side whereas the enamel is smooth on the labial side. These monocuspid teeth are large and fang-like. The numerous smaller teeth of the maxilla show three, four and five cusps. These are very similar to the teeth of the Triassic pterosaur Eudimorphodon ranzii. The humerus shows a thinner construction than that seen in other Triassic pterosaurs. The femur is quite unusual with a caput femoris perpendicular to the shaft. The bones of the extremities are almost twice as long as the ones from the largest Triassic specimen E. ranzii (MCSNB 2888). The newly described pterosaur is an adult, with a wingspan of approximately 135 cm. A morphofunctional analysis suggests that R. filisurensis was a highly specialized piscivore and possibly a skim-feeder. 相似文献
7.
A new anurognathid pterosaur specimen from the Middle Jurassic Tiaojishan Formation of Qinglong, northern Hebie Province is described. The new specimen is referred to Dendrorhynchoides, based on the general morphology of the skeleton, but it represents a new species, named here as Dendrorhynchoides mutoudengensis sp. nov.. It is characterized by the presence of short, robust and straight teeth, and bearing wing metacarpal approximately 40% of the length of humerus. The new specimen provides further osteological information for anurognathid pterosaurs, especially the presence of a relatively elongate tail. 相似文献
8.
In this study, we erect Sauroniops pachytholus gen. et sp. nov., a large-bodied theropod dinosaur from the Cenomanian (Upper Cretaceous) of Morocco, on the basis of an almost complete frontal showing a unique combination of features including a naso–frontal suture extended along 40% of the frontal length, a thick dome in the anterolateral corner of the dorsal surface, a trapezoidal prefrontal facet that is restricted to the anterodorsal margin of the lateral surface of the frontal with no participation in the orbital roof and separated from the lacrimal facet by a narrow vertical lamina, a hypertrophied ‘D-shaped’ lacrimal facet that is four times the anterior depth of the postorbital facet, and a raised posteromedial margin of the dorsal surface describing a saddle with the anterolateral dome and confluent with a series of anteromedial rugosities. Phylogenetic analysis found robust support for placing Sauroniops among the basal carcharodontosaurids and related to Eocarcharia, showed that some of the unusual features of the new theropod were convergently acquired by abelisaurids, and revealed a mosaic pattern in the evolution of the carcharodontosaurid skull table. The frontals of Sauroniops and Carcharodontosaurus, both from the ‘Kem Kem compound assemblage’ of Morocco, show comparable size but differ in the extent of the naso–frontal articulation, the shape and disposition of the prefrontal and lacrimal articulations, the development of dorsal ornamentation and the morphology of the supratemporal fossa. Among carcharodontosaurids, the skull table developed unique configurations among each lineage and appears diagnostic at the species-level. The dome-like frontal in Sauroniops may indicate head-butting behaviour in this taxon or evolved for visual display. 相似文献
9.
A new specimen of pterosaurian metacarpal IV from the Early Cretaceous (Berriasian) Durlston Formation of Dorset, southern England, closely resembles those of the Chinese dsungaripterid Dsungaripterus weii Young, 1964 and the Central Asian azhdarchid Azhdarcho lancicollis Nessov, 1984. However, the new specimen lacks the thickened bony wall typical of Dsungaripteridae and is therefore regarded as azhdarchoid. An mcIV with a markedly offset distal condyle with well-developed diaphyseal constriction behind the distal condyle and asymmetrical condylar margins may be an autapomorphy of Dsungaripteridae + Azhdarchoidea, while the same condition with bone thickening may typify Dsungaripteridae. The new specimen also provides osteological evidence supporting claims for large wing-spanned pterosaurs in the Berriasian of southern England based previously only on ichnological finds. The new specimen suggests a wingspan of between 2.9 and 3.7 m and represents the largest pterosaur from the Berriasian. 相似文献
10.
中国辽宁西部早白垩世翼龙类化石非常丰富,其上部的九佛堂组翼龙类组合以含有丰富的无齿的古神翼龙科、朝阳翼龙科等进步类型而与下部的义县组翼龙类组合相区别。本文描述了辽宁西部建昌盆地九佛堂组一新的大型翼龙类化石,其以上下颌无齿、吻端指数为3.7、前颌骨背支细长且封闭鼻眶前孔背缘、很大的鼻眶前孔后端超过上下颌关节位置、轭骨的上颌骨突基部宽大而应被归入朝阳翼龙科(Chaoyangopteridae)神州翼龙属(Shenzhoupterus)。其以较大的体形(翼展2.05 m)、平直的上下颌咬合面、轭骨的眶后骨突较泪骨突长且基部略宽、第4～7颈椎长度依次减小等特征,区别于朝阳神州翼龙(Shenzhoupterus chaoyangensis),而被命名为三亚神州翼龙(新种)(Shenzhoupterus sanyainus sp. nov.)。这是辽宁西部早白垩世翼展最大且不具牙齿的翼龙类属种,它的发现丰富了九佛堂组翼龙类组合内容,对认识朝阳翼龙科的骨骼形态与生态习性亦具有积极意义。 相似文献
11.
Gerald Grellet-Tinner Michael B.Thompson Lucas E.Fiorelli Eloísa Argaaraz Laura Codorniú E.Martín Hechenleitner 《地学前缘(英文版)》2014,5(6):759-765
The increasing number of fossil pterosaur eggs sheds light on nesting environments and breeding be- haviors of these extinct flying reptiles. Here we report the first partial three-dimensional egg of the pterosaur, Pteroduustro guinazui, from central Argentina. The specimen was discovered from the same Albian deposits as the exceptional R guinazui embryo described in 2004. Microscopic characterizations indicate a pristine preservation of the 50 Bm thick calcium carbonate, which differs significantly from the soft shell of Chinese pterosaur eggs. Estimate of the eggshell conductance implies that the nest had a minimum moisture content of 75%. This moisture estimate, combined with geological and taphonomical data, suggests that P. guinazui may have adopted a nesting strategy similar to those of grebes and flamingos rather than being buried on land, as previously hypothesized. Moreover, our results demon- strate that the nesting paleoenvironment of this pterosaur species was closely linked to a mesohaline lacustrine ecosystem in a basin governed by regional tectonic subsidence, a setting characteristic for the feeding and reproduction of modern flamingos. 相似文献
12.
13.
Fossil snakes are relatively well represented in the Upper Cretaceous of northern Africa, with material known from Morocco, Sudan, Egypt, Libya, Algeria, and Niger. The Moroccan Kem Kem beds have yielded a particularly diverse snake assemblage, with Simoliophiidae, Madtsoiidae, ?Nigerophiidae and several unnamed taxa co-occurring. These fossils are important for our understanding of the early evolutionary history of snakes, and may shed light on the ecology and initial diversification of basal snakes. We describe a new taxon, Norisophis begaa gen. et sp. nov., from the Kem Kem beds of Begaa, in southeast Morocco. It is characterised by a marked interzygapophyseal constriction, parazygantral foramina, an incipient prezygapophyseal process, and an anterio-posteriorly short centrum. Several characteristics shared with Najash, Seismophis, Madtsoiidae, and Coniophis suggest that Norisophis is a stem ophidian. N. begaa further increases the diversity and disparity of snakes within the Kem Kem beds, supporting the hypothesis that Africa was a mid-Cretaceous hotspot for snake diversity. 相似文献
14.
《China Geology》2020,3(1):1-7
A new dsungaripterid pterosaur, Ordosipterus planignathus gen. et sp. nov., is established on the incomplete articulated lower jaws from the Lower Cretaceous Luohandong Formation in Otog Qi, Ordos Region, Inner Mongolia, China. It differs from other dsungaripterids mainly by having broad and low dentary at and just behind the mandibular symphysis, flat dentary dorsal plane forming the distinct lateral ridge with the curved dentary lateral side, and lower alveoli arranged along the dentary dorsolateral margin with wide spacing that increases from rostral to caudal. It represents the first diagnostic pterosaur from the Ordos Region in Inner Mongolia, and further enlarges the geographical distribution of the family Dsungaripteridae from northwestern China (together with western Mongolia) to central North China. 相似文献
15.
Laura Codorniú Zulma Gasparini Ariana Paulina-Carabajal 《Journal of South American Earth Sciences》2006,20(4):383-389
A small to medium-sized pterodactyloid pterosaur (wingspan approximately 1.10 m) from the Upper Jurassic (middle-late Tithonian) marine deposits of the Vaca Muerta Formation of Patagonia (Los Catutos area, central Neuquén Province, Argentina) is reported. The specimen lacks the skull but constitutes a nearly complete postcranial skeleton, which includes cervical and dorsal vertebrae; a few thoracic ribs; both pectoral girdles; the left pelvic girdle; a proximal right wing (humerus, ulna, and radius) and metacarpal IV; a left wing that lacks only wing phalanx four; and both hindlimbs, the right one without the foot. Ontogenetic features suggest that the new fossil corresponds to a relatively mature individual, probably a subadult. Observed characters support its assignment to the Archaeopteroactyloidea, a basal clade within the Pterodactyloidea. This specimen is the second pterosaur from Los Catutos and the most complete Jurassic pterosaur so far known from South America. 相似文献
16.
A giant humerus (450 mm total length) belonging to one of the largest pterosaur recorded in South America is described. The specimen (UNCUYO-LD 350) was discovered in the Upper Cretaceous (upper Coniacian – lower Santonian) Plottier Formation of the Mendoza Province, northern Neuquén Basin, Argentina. It was found associated with a smaller pterosaur specimen represented by around thirty postcranial bones. The specimen is assigned to Tapejaroidea and show characters of both Tapejaridae and Azhdarchidae. Based on comparisions with other Azdharchidae species, a wingspan of 9.1 m is estimated for UNCUYO-LD 350, showing that giant pterosaurs were present in South America during the Upper Cretaceous. 相似文献
17.
David W. E. HONE 《《地质学报》英文版》2012,86(6):1366-1376
18.
DONG Zhiming lv Junchang Research Center of Paleontology Stratigraphy Jijin University Changchun Institute of Paleontology Paleoanthropology Chinese Academy Sciences Beijing Institute of Geology Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2005,79(2):164-167
Based on a nearly complete lower jaw from the Early Cretaceous of Liaoning Province, a new ctenochasmatid pterosaur: Liaoxipterus brachyognathus gen, et sp. nov. is erected. Liaoxipterus brachyognathus is different from any known pterosaurs with skulls preserved from western Liaoning Province and its peripheral areas in that the anterior part of the mandibular symphysis is expanded, being widest between the fourth alveolus of each side. Liaoxipterus brachyognathus is assigned to Ctenochasmatidae based on the following characters: the rounded anterior end of the lower jaw is spatulated and dorsoventrally flattened and marked heterodonty in the dentition is absent. It differs from other ctenochasmatid pterosaurs in having relatively small number of teeth. Liaoxipterus is distinguished from some ornithocheirids, which have expanded anterior parts of the mandibular symphyses, such as Anhanguera piscator,Coloborhynchus robustus in which the teeth of the new pterosaur are not as variable. 相似文献
19.
Company Julio Ruiz-Omeñaca José Ignacio Pereda Suberbiola Xabier 《Geologie en Mijnbouw》1999,78(3-4):319-333
Fragmentary remains, including cervical vertebrae and limb bones, of a large pterosaur from the Upper Cretaceous of Tous, province of Valencia (Spain), are described. The material was recovered from lacustrine beds in the upper part of the Calizas y Margas de Sierra Perenchiza Formation, which is probably Maastrichtian in age. Six fragments of vertebrae allow a reconstruction of the anatomy of the mid-series cervicals of the animal. The general morphology of the cervical vertebrae is closely similar to that of the long-necked Azhdarchidae. Compared to other azhdarchids, the Valencia pterosaur shows minor differences from the genera Azhdarcho and Quetzalcoatlus, and is here provisionally referred to as Azhdarchidae indet. A wingspan of about 5.5 m is calculated by comparison with other known azhdarchids. This is the second azhdarchid pterosaur described from the Iberian peninsula. It confirms the wide distribution of this group of large pterosaurs at the end of the Cretaceous. 相似文献
20.
The Late Cretaceous (Santonian) continental vertebrate locality of Iharkút, western Hungary has provided numerous azhdarchid pterosaur remains including the recently described, Bakonydraco galaczi. Since the first report of these fossils, additional remains have been discovered that improve considerably our knowledge of some aspects of the anatomy of azhdarchid pterosaurs. New cranial material described here indicates an edentulous, non-crested premaxillary rostrum in Bakonydraco similar to that of Quetzalcoatlus and reveals that this rostrum was considerably thinner and more lightly built than the relatively massive, pointed mandibular symphysis. In addition, the contact surface of the upper and lower jaws of Bakonydraco at least in the symphyseal region was more similar to Tapejara wellnhoferi than to other azdarchids: the contact is irregular and the premaxilla does not fit closely the rostral part of the mandible. Among the postcranial material the atlas-axis complex possessing lateral pneumatic foramina is of great importance because it further supports the notion of interspecific variability of vertebral pneumaticity among pterosaurs. 相似文献