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二○一○年七月 地 球 学 报 Jul. 2010 第三十一卷 增刊 1: 38-39 Acta Geoscientica Sinica Vol.31 Supp.1: 38-39 www.cagsbulletin.com www.地球学报.com

中国新疆北部早白垩世魏氏准噶尔翼龙 (Dsungaripterus weii)化石新材料

厉大亮 1), 姬书安 2) 1)中国地质大学,北京 100083; 2)中国地质科学院地质研究所,北京 100037

摘 要: 魏氏准噶尔翼龙( weii)是一类翼展可达 5 米的大型翼龙类化石,已知的化石材料均产 自新疆准噶尔盆地西北缘乌尔禾–德仑山一带早白垩世吐谷鲁群地层中。最近,一件新的保存完整的头骨化 石发现于准噶尔盆地东缘五彩城附近,进一步扩大了魏氏准噶尔翼龙的地理分布范围。同时新材料还显示 出该翼龙头骨的一些新特征:鼻骨具有长的较细的腹突、鼻骨后突上存在前后排列的一小窝及一小孔,丰 富了我们对该翼龙头骨形态的认识。

New Material of the Early Cretaceous Dsungaripterus Weii from Northern , Northwest

LI Da-liang1) and JI Shu-an2) 1) China University of Geosciences, Beijing 100083, China; 2) Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China

Dsungaripterus weii was a large crested pterosaur The oval orbit is comparatively small, with its long with a wingspan of up to 5 m in adults. It is the repre- diameter less than one third the longitudinal length of sentative genus and species of the Family Dsungarip- the nasoantorbital fenestra. It is positioned high up on teridae. Diagnostic remains are known only from the the skull, as shown by its ventral border which lies Early Cretaceous Tugulu Group of Urho–Delunshan above the mid-point level of the caudal margin of the region, at the northwestern margin of the Junggar Ba- nasoantorbital fenestra. The anterior portion of pre- sin, northern Xinjiang Uygur AutonomousCAGS Region. Recently, a new specimen including a nearly complete skull and mandibles was excavated near Wucaicheng, at the eastern margin of the Junggar Basin. This find is the first definite occurrence of Dsungaripterus weii outside the Urho–Delunshan region, and thus provides us with new information about the paleogeographical distribution of this pterosaur. The newly discovered skull and mandibles (Col- lection no. 05-01-09, housed in the China University of Geosciences Museum in Beijing) are nearly com- plete (Fig. 1), only the posterior processes of the pa- rietals are missing. The skull is 423 mm long as pre- served, falling within the size range of other reported adult individuals. The cranial lateral view appears longitudinally triangular in outline with the occipital margin inclining antero-ventrally. The large nasoan- torbital fenestra is 146 mm long, occupying 1/3 of the Fig. 1 New specimen of Dsungaripterus weii (05-01-09), total skull length. This fenestra appears sub-triangular skull and mandibles in the left (top) and right (bottom) lat- in lateral view, with its caudal margin almost vertical. eral views

Supp.1 LI Da-liang et al.: New Material of the Early Cretaceous Pterosaur Dsungaripterus Weii from Northern Xinjiang,… 39

maxilla is narrow, pointed, and slightly curved dor- anatomy of Dsungaripterus weii. sally. There is a well-developed sagittal crest, 33 mm Dsungaripterids are reported from northwestern in height and 179 mm in preserved length. This crest China (northern Xinjiang), western Mongolia, Japan, starts above the position of the fifth rostral tooth. The and Chile. Northern Xinjiang is the main distribution mandibular symphysis is long, occupying about 40% area for dsungaripterids, where three genera and spe- of total mandibular length. The tallest point of the cies have been identified: Dsungaripterus weii, symphysis is at its posterior end. Anteriorly, the sym- Noripterus complicidens, and Lonchognathosaurus physis becomes gradually narrower, and ends in a acutirostris. Dsungaripterus weii was described on the pointed tip. Its anterior portion is also curved dorsally, basis of more than 30 individuals, all from the coinciding with the anterior portion of the premaxilla. Urho–Delunshan region, at the northwestern margin of There are 14 rostral teeth extending from the the Junggar Basin. The new specimen was collected mid-point of the rostrum to a point about one third the from Wucaicheng near the eastern margin of the basin, length from the anterior end of the nasoantorbital roughly 250 km from the northwestern margin of the fenestra. The posterior teeth are more robust than basin. It is the first characteristic material of Dsun- those at the anterior end of the tooth row. The tooth garipterus weii from outside the Urho–Delunshan re- crowns are short and blunt and widely spaced. Each gion, enlarging the geographical distribution of this ramus of the mandibles bears 11 teeth. Most of these genus and species. In northern Xinjiang, all the dsun- are characteristic of dsungaripterids; moreover, the garipterid remains have been recorded from the Tu- upwardly curved and pointed rostrum and anterior gulu Group (upper Lower Cretaceous). Sedimentary mandibles further indicate that the new specimen strata near Wucaicheng, have yielded other reptiles should be assigned to Dsungaripterus weii. including turtles and theropods. This indicates that Two new features are also present on this speci- similar paleoenvironments existed between the north- men. Firstly, the left nasal bears a long and slender western and eastern margins of the Junggar Basin ventral process that is directed subventrally and during the late Early Cretaceous. slightly less than half the height of the nasoantorbital This study was funded by the Geological Survey fenestra. Such a process is not observed on the right of China (grant no. 1212010911038) to JI Shu-an, and nasal, and is likely not preserved. This long ventral the China University of Geosciences (Beijing) to LI process of the nasal was not confirmed in Dsungarip- Da-liang. terus weii before. Compared with that in some cteno- chasmatids, the ventral process of nasal in the new specimen is positioned more anteriorly. Secondly, there is a small fossa and a small foramen on the pos- terior process of nasal, at the corner of the dorsal and caudal margins of the nasoantorbital fenestra. Both are somewhat oval in shape, and the fossa is anterior to the foramen. Both of them are evidently exposed on the left side of the skull although their partial borders are overlapped (Fig. 2). Unfortunately, the foramenCAGS on the right nasal is completely covered by the right lac- rimal. An elliptical foramen on the nasal was also re- ported in Gegepterus changi, a member of the Cteno- chasmatidae from the Lower Cretaceous in western Liaoning. These features, such as the long ventral Fig. 2 Left nasal in lateral view, showing the ventral proc- process, and oval fossa and foramen of the nasal fur- ess, fossa and foramen in the new specimen of Dsungarip- ther enrich our knowledge concerning the cranial terus weii (05-01-09)