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1.
Jingmai K. O'Connor Thomas A. Stidham Jerald D. Harris Matthew C. Lamanna Alida M. Bailleul Han Hu Min Wang Hai‐Lu You 《植物分类学报：英文版》2022,60(5):1172-1198
We describe six specimens consisting of cranial remains and associated partial presacral axial series belonging to ornithuromorph birds from the Changma locality of the Lower Cretacous Xiagou Formation of northwestern Gansu Province, China. Comparison among specimens is limited by the paucity of overlapping elements, their differing exposed views, and, in some specimens, poor preservation. Despite this, three separate taxa are represented, evidenced by differences in their dentary dentitions: one specimen is edentulous, another has sharp, closely spaced, relatively high-crowned and peg-like teeth, and a third preserves blunt, relatively low-crowned teeth placed in a communal groove, a morphology previously reported among adult birds only in Hesperornithiformes. We propose that the high-crowned specimen may be referred to Gansus yumenensis based on shared similarities with the closely related Iteravis huchzermeyeri, including a very similar dentition and an edentulous premaxilla with elongate, unfused frontal processes and no palatal processes. The two other specimens are considered new taxa, for which we erect the names Meemannavis ductrix gen. et sp. nov. and Brevidentavis zhangi gen. et sp. nov. These new specimens confirm that the Changma locality is dominated by ornithuromorph birds and contribute to a better understanding of this important avifauna. The observed variation in dental morphology hints at trophic diversity like that observed in ornithuromorphs from the penecontemporaneous Jehol Group of northeastern China. 相似文献
2.
SHU‐AN JI JESSIE ATTERHOLT JINGMAI K. O'CONNOR MATTHEW C. LAMANNA JERALD D. HARRIS DA‐QING LI HAI‐LU YOU PETER DODSON 《Zoological Journal of the Linnean Society》2011,162(1):201-219
In recent years, the Lower Cretaceous (Aptian) Xiagou Formation has yielded approximately 100 avian partial skeletons, many with soft‐tissue traces, from sites in the Changma Basin of Gansu Province, north‐western China. The most abundant taxon amongst these is the ornithuromorph Gansus yumenensis, but enantiornithines have also been identified in the sample. Here we describe two incomplete, semi‐articulated appendicular skeletons, the first consisting of a partial left pelvic girdle and complete pelvic limb, and the second comprised of a nearly complete right pelvic limb. Both specimens bear characteristics diagnostic of Enantiornithes, and are referred to a new taxon, Qiliania graffini gen. et sp. nov. The exceptional, three‐dimensional preservation of these specimens (compared to the crushed, nearly two‐dimensional condition of most other Early Cretaceous avian fossils) reveals new information regarding enantiornithine anatomy, evolution, and diversity. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 201–219. 相似文献
3.
We report on a new species of basal ornithuromorph bird, Piscivoravis liigen. et sp. nov., based on a well-preserved and nearly complete specimen from the Lower Cretaceous Jiufotang Formation in western Liaoning Province, northeastern China. The new specimen preserves several unique anatomical features previously unreported in Early Cretaceous ornithuromorphs, such as a robust furcula with strongly tapered omal tips, a broad sternum without craniocaudal elongation and large and strongly curved manual unguals. Phylogenetic analysis indicates that Piscivoravis is more derived than Archaeorynchus, but in a basal polytomy with Jianchangornis, Patagopteryx, and the clade including all more derived ornithuromorphs. The preserved wing and tail feathers provide new information on feather diversity and evolution in Early Cretaceous ornithuromorphs. The preservation of fish bones ventral to the dentary and in the stomach provides direct evidence that the new species was piscivorous – previously only reported in Yanornis, and as in some living birds, was capable of moving food bidirectionally through the alimentary canal.http://www.zoobank.org/urn:lsid:zoobank.org:pub:92F23126-9E89-4E51-9700-C6608E0D66EB 相似文献
4.
Ornithuromorpha is the most derived avian group in the Early Cretaceous, advanced members of which encompass all living birds (Neornithes). Here we report on a new basal ornithuromorph bird, Bellulia rectusunguis gen. et sp. nov., represented by a nearly complete skeleton from the Early Cretaceous Jehol Biota in northeastern China. A comprehensive phylogenetic analysis resolved the new taxon in a basal position that is only more derived than Archaeorhynchus and Jianchangornis among ornithuromorphs, increasing the morphological diversity of basal ornithuromorphs. The new specimen has a V‐shaped furcula with a short hypocleidium, a feature otherwise known only in Schizooura among Cretaceous ornithuromorphs. We discuss the implications of the new taxon on the evolution of morphology of primitive ornithuromorphs, particularly of pectoral girdle, sternum and limb proportion pertaining to powered flight. The preserved gastroliths and pedal morphology indicate herbivory and lakeshore adaption for this new species. © 2015 The Linnean Society of London 相似文献
5.
甘肃玉门下沟地区早白垩世下沟组介形类 总被引：2，自引：1，他引：2
甘肃玉门下沟地区下沟组介形类化石十分丰富,该地区下沟组介形类化石共计9属4亚属,21种,本文描述了其中4新种,即Cypridea(Cyamocypris)xiagouensissp.nov.,Cypridea(Cypridea)subunicostatasp.nov.,Stenestroemiasubpeculiarissp.nov.和Stenestroemiaxiagouensissp.nov.。该介形类化石组合尤以Cypridea最为繁盛,通过分析介形类属种的形态特征和化石组合特征并结合岩性特征,推断下沟组的地质时代为早白垩世巴列姆期;并认为下沟组为水动力较弱的淡水-微咸水河湖相沉积。 相似文献
6.
本文描述了甘肃玉门红柳峡下沟组的介形类化石共5属4亚属、13种。其中1新属、6个新种、1个比较种。根据介形类特征和地理分布,推测下沟组的时代为早白垩世巴列姆期;同时结合玉门红柳峡下沟组的岩性特征,认为该组为淡水微咸水河湖相沉积。 相似文献
7.
本文报道了甘肃省高台县马营河剖面下沟组上部轮藻化石5属6种、1相似种和1未定种：Clypeator jiuquanensis (S. Wang) L. Grambast, Aclistochara huihuibaoensis S. Wang, A. cf. huihuibaoensis S. Wang,Mesochara stipitata (S. Wang) Z. Wang, Mesochara crassistipitata Zhang et Meng, Peckisphaera paragranulifera(S. Wang) Fu et Lu, Sphaerochara valida (Z. W. Li) comb. nov. , Sphaerochara sp.。讨论相关种的国内外地层分布,将下沟组上部地质时代归为早白垩世巴雷姆期。 相似文献
8.
继1984年首次报道甘肃玉门昌马发现的早白垩世甘肃鸟及2006年记述多件甘肃鸟标本以来,再次对发现于2004～2006年间的9件甘肃鸟标本进行形态的详细观察,补充描述甘肃鸟新的骨骼特征,包括侧面保存的胸骨、有较完整的镰刀形龙骨突及胸骨背侧特征等;部分前肢骨骼上有位于关节位置、呈短长方形的尺腕骨和桡腕骨;指式"2-3-1",小指骨的爪节完全退化消失;后肢各趾中第1趾节最长,趾爪短小且弯曲度小;第Ⅰ趾相对较短、细弱,与其他趾相对握;第Ⅲ趾粗壮,略短于第Ⅳ趾。在胫跗骨和跗跖骨关节处保存有鳞片状的皮肤印痕,趾骨间有蹼的印痕。通过指示性骨骼测量的三元分析,得出甘肃鸟是一类善飞的潜水鸟,其习性接近于部分现生的鸭科成员,与之前有关甘肃鸟生活习性的推测较为接近。 相似文献
9.
The publication of the scientific name Monjurosuchus splendens in 1940 documented the first tetrapod fossil of the later world-renowned Jehol Biota. For more than half a century since this discovery, however, Monjurosuchus has remained as a monotypic genus of the family Monjurosuchidae, and the relationships of the family with choristoderes have not been correctly recognized until quite recently. In this paper, a new monjurosuchid is named and described based on a nearly complete skull and postcranial skeleton from the Early Cretaceous Chiufotang Formation exposed near Chaoyang, western Liaoning Province, China. This new material documents the first occurrence of monjurosuchid choristoderes outside the type Lingyuan area, and extends the geological range of the family from the Yixian Formation to the younger Chiufotang Formation. Cladistic analyses were conducted with inclusion of monjurosuchids, and the results support the placement of the family Monjurosuchidae as a primitive clade outside the Neochoristodera. A new classification scheme is proposed for choristoderes on the basis of the recovered phylogenetic framework of the group. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 427–444. 相似文献
10.
福建禾口盆地早白垩世禾口组的类三角蚌：兼论Trigonioididae的分类 总被引：2，自引：1，他引：1
讨论Trigonioididae的分类和记述产于福建宁化禾口盆地下白垩统禾口组的Trigonioides(s.s.)elegans sp.nov., Trigonioides(s.s.) quadratus Gu et Ma.这两种的主要区别在于Tri-gonioides (s.s.) elegans sp.nov. 的前部壳面放射脊精致且由壳顶延伸至前缘附近,但Trigoni-oides (s.s.) quadratus Gu et Ma的前部壳面放射脊多隐伏或消失.化石产出层位可能与朝鲜南部霞山洞组相当. 相似文献
11.
In this paper, a new species of the genus Phyllocladoxylon on the basis of fossil woods from the Fuxin Formation in Western Liaoning province, Phyllocladoxylon xinqiuensis sp. nov., is reported and its anatomic structures are described. 相似文献
12.
Sha Jin-geng 《古生物学报》1992,(3):309-312
This paper describes three new species of Pisidiidae, Pisidium (P.) zhushutangense, Sphaerium(S.) pyrum and Sphaerium (S.) fujianense, assoeiated with very abundant Plicatounio (P.) naktongensis Kobayashi et Suzuki, Plicatounio (P.) fujianensis Gu et Ma and Trigonioides (T.) quadratus Gu et Ma from the Lower Cretaceous upper Hekou Formation of Zhushutang, Hekou Basin, Ninghhua, Fujian. In Japan, the last two species, Sphaerium (S.) pyrum and Sphaerium (S.) fujianense, or their affinis coexist with each other in the upper Wakino Subgroup, the lower Wakamiya and upper Wakamiya Formations, and the lower Inakura Formation, Yamaji Shale, which very probably can be correlated with the upper Hekou Formation yielding these two species.The distinction between Pisidium and Sphaerium is summarized in Table I. 相似文献
13.
尾羽龙(Caudipteryx)的新材料及其重要骨骼特征的补充和修订 总被引：16，自引：7，他引：16
尾羽龙和原始祖鸟一起被认为是最早发现的带有真正鸟类羽毛的恐龙（Ji et al., 1998）,迄今已发现的尾羽龙包括邹氏尾羽龙（Caudipteryx zoui）和董氏尾羽龙（Caudipteryx dongi）两种（周忠和、汪筱林,2000）,前者包括保存在中国地质博物馆的NGMC 97*4朅和NGMC 97*9朅两件标本,而后者依据的材料仅为保存在中国科学院古脊椎动物与古人类研究所的V 12344。以上标本都不是十分完整。本文依据最近新发现的两件几乎完整的尾羽龙标本,对该属的一些重要形态特征进行补充和修订,以期对其系统关系的讨论及其他相关理论问题的研究提供新的… 相似文献
14.
A new genus with a new species of Saldidae, Brevrimatus pulchalifergen. et sp. n., is described and illustrated. The fossil specimen was found from the Early Cretaceous Yixian Formation of Duolun County, Inner Mongolia, China. Phylogenetic analyses within Saldidae were performed, and the results indicate Brevrimatus pulchalifergen. et sp. n. should be assigned to the subfamily Chiloxanthinae. 相似文献
15.
辽西义县组孢粉植物群指示的古气候条件 总被引：4，自引：0，他引：4
迄今为止,在辽西北票义县地区的下白垩统义县组二段沉积层中,已发现孢粉化石62属,82种,藻类化石3种。本文对产于不同地点沉积层中的孢粉化石进行了系统研究和总结。根据孢粉母体植物形态和生态特征、生长的气候环境和干湿度环境,对义县组二段的孢粉植物群进行了植被类型、气候带类型和干湿度类型的统计和划分,认为义县组二段沉积时期,其孢粉植被类型为针叶林,所处的气候环境为湿润的亚热带一暖温带。由于植被成分中存在落叶阔叶植物和旱生植物,推测气候环境存在季节性变化,间有干旱一半干旱气候条件。 相似文献
16.
冀辽一带的土城子组和大北沟组对中国北方侏罗系-白垩系划分对比具有重要的意义.关于它们的时代目前还存在不同的看法,相关的孢粉地层学研究也比较粗略.本文研究了冀北滦平县井上村三岔子剖面土城子组和大北沟组的孢粉组合,共观察统计到50属28种及若干未定种.土城子组Classopollis-Cooksonites-Ephedri... 相似文献
17.
本文报道的Pagiophyllum属4新种,是在对它们的角质层构造进行了研究的基础上建立的,标本产自浙东新昌县苏秦村附近的馆头组,共生的植物化石尚有Ruffordia goepperti, Zamiophyllum buchianum, Pseudofrenelopsis parceTflogoso, P. papillosa, Cupressinocladus elegans等;另在苏秦村南面镜岭的相当层位中还找到双壳类化石Plicotounio(P.)zheijiangensts。这些化石都表明馆头组的地质时代为早白垩世。 相似文献
18.
?Paralycoptera wui Chang & Chou, 1977 from the Early Cretaceous of China is redescribed herein through a re‐examination of the original materials, as well as observations on some newly collected specimens. The use of the peeling method has revealed much of the new or revised information on its osteology, e.g. aspects of the nasal, infraorbitals, retroarticular, preopercle, extrascapular, basihyal toothplate, epineural, pelvic fin, caudal skeleton and scales. The phylogenetic relationships of ?Paralycoptera and other osteoglossomorphs are re‐evaluated. The cladistic analysis largely agrees with the previous hypothesis that ?Paralycoptera is not a ?lycopterid, but rather a stem osteoglossoid. ?Paralycoptera is excluded from notopteroids and exhibits the following derived characters of the Osteoglossoidei: (1) palatal area behind and below orbit completely covered by infraorbitals; (2) jaw articulation under posterior portion of orbit; (3) opercle depth twice or more its width; (4) first pectoral fin ray much enlarged and long, extending posteriorly beyond origin of pelvic fin. ?Singida and ?Phareodus are regarded as different levels of osteoglossoids above ?Paralycoptera. ?Singida shares the following derived characters with ?Phareodus plus extant osteoglossoids: (1) jaw articulation posterior to orbit; (2) anterior process of hyomandibula in contact with entopterygoid; (3) subopercle small and anterior to opercle. ?Phareodus shares the following derived characters with extant osteoglossoids: (1) supraorbital and otic sensory canals connected; (2) one uroneural; (3) reticulate furrows present over entire scale. 相似文献
19.
记述了辽宁西部九佛堂组和义县组中华弓鳍鱼一新种:辽宁中华弓鳍鱼Sinamia liaoningensis,并与该属的其他种进行了比较.新材料具有中华弓鳍鱼科的3个定义特征:单一的顶骨,三对额外肩胛骨和膜质翼耳骨短并与顶骨等长,无疑应归入该科.新种的后眶下骨较小,背鳍长大,鳞片菱形,因此,归入中华弓鳍鱼属.辽宁中华弓鳍鱼在以下几个方面不同于中华弓鳍鱼的5个已知种:体型短粗,吻骨较短,鼻骨近四方形,围眶骨较多(6),前鳃盖骨强烈弯曲,背鳍条较少(18),尾鳍条较多(16),臀鳍鳍基起点到鱼体背缘的鳞列较多(32),鳞片后缘不具锯齿,尾鳍具有纤维状的角质鳍条. 相似文献
20.
辽宁早白垩世义县组一新的三尖齿兽类 总被引：1，自引：1，他引：1
描述了戈壁锥齿兽科 (Gobiconodontidae)一个新的属种———陆家屯弥曼齿兽 (Meeman nodonlujiatunensisgen .etsp .nov.)。标本产于辽宁西部朝阳市上园镇陆家屯下白垩统义县组一段的凝灰质砂岩层中 ,为一具完整齿列的左下颌骨。新属与戈壁锥齿兽 (Gobiconodon)共有以下区别于其他三尖齿兽类的特征 :2颗下门齿 ,i1增大 ,后部门齿、犬齿和前部前臼齿尖锥形 ,前臼齿具有高的中央尖和小的附尖 ,i～p1向前平伏。因此 ,新属被归入戈壁锥齿兽科。弥曼齿兽与戈壁锥齿兽及其相近属的区别在于 :下门齿和下犬齿更加平伏 ,i1在比例上更大 ,而i2则更小 ;最后一枚下前臼齿与第一枚下臼齿之间没有齿隙 ;前臼齿退化 ;下臼齿长度大于高度 ,主尖向后倾斜 ,与b尖和c尖相比 ,a尖较低 ,m1显著小于m2～ 4。新属下臼齿没有齿带 ,与爬兽 (Repenomamus)相似 ,而与戈壁锥齿兽不同。基于与爬兽齿列的对比 ,讨论了戈壁锥齿兽类的齿式 ,认为其应具有两颗门齿 ,而不是以前认为的 1颗门齿 ,从而将戈壁锥齿兽类下齿列齿式修订为 :2·1·2～ 3·5。 相似文献