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1.
记述了在四川自贡大山铺发现的孙氏鳄一新种———蜀南孙氏鳄 (Sunosuchusshunanensissp .nov .)。新种窄长的吻部 ,小的颅顶平台 ,额骨沿中线具一纵嵴 ,一对裂隙状的前腭孔位于眶下孔之前方 ,方骨腹面的嵴B特别发育等 ,与孙氏鳄的其他种很相似 ,但新种的吻部特别窄长 ,为吻后部长度的 3倍 ,上颌凹特别发育 ,颅顶平台短而宽 ,颞间部宽度大于眶间部宽度 ,泪骨在眼眶前缘处隆起成嵴 ,下颞孔小 ,呈裂隙状 ,鳞骨侧缘不增厚 ,也无附着上耳盖的沟嵴状构造 ,基枕骨侧缘和外枕骨内腹缘具一明显的隆嵴等 ,与孙氏鳄的其他种有明显区别  相似文献   

2.
四川自贡大山铺西蜀鳄一新种   总被引:1,自引:1,他引:0  
高玉辉 《古脊椎动物学报》2001,39(3):177-184,T001
记述了西蜀鳄一新种──大山铺西蜀鳄(Hsisosuchus dashanpuensis),新种保存了完好的吻端,填补了西蜀鳄在这方面的缺失。新种的内鼻孔位置靠前,上颌骨和腭骨构成其边缘;眶下孔存在但较小;产于自贡市大山铺下沙溪庙组。  相似文献   

3.
记裂头鳄属(Dibothrosuchus)一新种   总被引:4,自引:4,他引:0  
本文记述的裂头鳄属-新种 (Dibothrosuchus xingsuensis sp. nov.)的标本采自云南禄丰盆地下禄丰组深红层.通过描述,对裂头鳄属属级特征作了补充.新种的头骨中鳞骨缺失降突;方骨极度向前背方伸展,形成大的耳凹,乌喙骨具后腹突,以及具有鳄类式的腕骨等,表明裂头鳄属应改属为楔形鳄科 (Sphenosuchidae).根据该科各属的头骨中方骨与脑颅侧壁的连接关系,可以清楚地看到楔形鳄科在这局部解剖学上存在一连续的发展过程.在形态上,裂头鳄属和南非的 Sphenosuehus (典型属)最为相近.  相似文献   

4.
辽宁下白垩统九佛堂组伊克昭龙一新种   总被引:3,自引:0,他引:3  
伊克昭龙 (Ikechosaurus)是一类长吻的离龙类 ,以前根据内蒙古的材料建立了孙氏种 (I.sunailinaeSigogneau Russell,1 981 )及高氏种 (I.gaoiL櫣etal.,1 999)。根据蒙古的材料建立的TchoiriamagnusEfimov ,1 979也于 1 983年被原作者归入本属。本文记述了辽宁义县皮家沟九佛堂组新发现的一个近于完整保存的骨架 (中国科学院古脊椎动物与古人类研究所标本编号 :IVPPV 1 32 83) ,并建立一新种 :皮家沟伊克昭龙 (Ikechosauruspijiagouensissp .nov .)。新种以下列特征区别于伊克昭龙其他种 :轭骨前伸约至泪骨之半 ;眶间距小于眼眶短径 ;眶后骨与后额骨不愈合 ;髂骨片前突不发育 ,颈区不收缩 ;四肢中桡胫骨与肱股骨之比相对较小。另外其荐前椎数目与孙氏种相同 ,为 2 5枚 ,比鳄龙属 (Champsosaurus)少 1枚 ;坐骨明显比孙氏种短 ;桡肱骨长度之比为 0 .5 8,胫股骨长度之比为 0 .60 ,在所知新离龙类 (Neochoristodera)中属最小 ;前肢腕骨至少 7块 ,后肢跗骨至少 6块 ;指 /趾式均为 2 3 4 4 3。在正型标本中其第二远侧跗骨在左右脚中不对称。提出眶后骨与后额骨的愈合与分离以及轭骨眶后支发育程度不能作为Simoedosaridae和鳄龙科间的鉴别特征 ;股骨内转子与股骨头分离不该作为高氏种的鉴定特征 ;新离龙类?  相似文献   

5.
四川资中侏罗纪一新的半椎鱼类及其生物地层意义   总被引:1,自引:1,他引:0  
本文记述的棘背天府鱼(新属新种)发现于四川资中沙溪庙组.它只有大的顶骨、少的次眶骨及无饰缘棘鳞等特征,与新鳞齿鱼(Neolepidotes)相似;另外具有很发达的棘状背嵴鳞、少的次眶骨及鳞片无杵臼式关节等特征,与半椎鱼(Semionotus)很相似.天府鱼以其长大的顶骨、较居后的颌关节、较短的眶前距、很发达的棘状背嵴鳞及无饰缘棘鳞等特征,有别于半椎鱼科中所有已知属.根据天府鱼和过去记述的鱼化石,仍认为含鱼层的时代可能为中佚罗世.  相似文献   

6.
黄线狭鳕骨骼的研究   总被引:5,自引:0,他引:5  
本文记述黄线狭鳕骨骼系统的结构,有以下特点:鼻骨发达,背面形成一深沟;额骨,翼耳骨,前鳃盖骨和围眶骨有发达的感觉管;额骨上有囟门,泪骨很发达,耳石特大;下鳃盖骨特别肥厚,后匙骨上端亦很肥厚,呈槌状。  相似文献   

7.
本文记述黄线狭鳕骨骼系统的结构。有以下特点:鼻骨发达,背面形成一深沟;额骨、翼耳骨、前鳃盖骨和围眶骨有发达的感觉管;额骨上有囱门;泪骨很发达;耳石特大;下鳃盖骨特别肥厚;后匙骨上端亦很肥厚,呈槌状。  相似文献   

8.
吴肖春  刘俊  李锦玲 《古脊椎动物学报》2001,39(4):251-265,T001
初步研究了山西省永和县桑壁镇铜川组二段产出的两件初龙形类化石标本 (IVPPV1 2 3 78,V 1 2 3 79) ,在此基础上建立了一新属新种———桑壁永和鳄 (Yonghesuchussangbiensisgen .etsp .nov .)。它以下列共存的衍生特征区别于其他初龙形类 (archosauriforms) :1 )吻部前端尖削 ;2 )眶前窝前部具一凹陷 ;3 )眶前窝与外鼻孔间宽 ;4)眶后骨下降突的后 2 / 3宽且深凹 ;5 )基蝶骨腹面有两个凹陷 ;6 )齿骨后背突相当长 ;7)关节骨的反关节区有明显的背脊 ,有穿孔的翼状的内侧突 ,以及指向前内侧向和背向的十分显著的后内侧突。由于缺乏跗骨的形态信息 ,目前很难通过支序分析建立永和鳄的系统发育关系。但可以通过头骨形态来推测永和鳄在初龙形类中的系统位置。永和鳄有翼骨齿 ,这表明它不属于狭义的初龙类 (archosaurians)。其通过内颈动脉脑支的孔位于基蝶骨的前侧面而不是腹面 ,在这点上永和鳄比原鳄龙科 (Proterochampsidae)更进步 ,这表明与后者相比永和鳄和狭义的初龙类的关系可能更近。在中国早期的初龙形类中 ,达坂吐鲁番鳄 (Turfanosuchusdabanensis)与桑壁永和鳄最接近 ,但前者由于内颈动脉脑支的孔腹位而比后者更为原始。根据以上头骨特征以及枢后椎椎体之间间椎体的存在与否 ,推测派克鳄 (Euparkeri  相似文献   

9.
产于宁夏同心地区中中新世红柳沟组的戈壁跳兔 (Alloptoxgobiensis)头骨化石 ,是Al loptox属头骨化石的首次发现。其主要特征是 :个体较大。颅顶平缓 ,额骨有眶上嵴且两侧平行。颞嵴、上枕骨、项嵴和枕外嵴发育。眶裂后的翼蝶骨上排列有 6个孔。有外颈动脉孔 ,颈静脉孔为圆形小孔。下颌骨水平支唇侧上缘前倾 ,垂直支前缘有一深沟 ,冠状突位于垂直支前缘唇侧壁中部 ,呈薄片状。基于头骨性状的支序分析结果表明 ,Alloptox与非洲的Kenyalagomys亲缘关系最近 ,应归入亚科Sinolagomyinae。Alloptox和Kenyalagomys可能起源于亚洲的共同祖先 ,由Sinolagomys或与其相近的属种演化而来 ,在新近纪早期迁入非洲。  相似文献   

10.
道虎沟化石层分布于内蒙古宁城县道虎沟以及毗邻的河北北部和辽宁西部等地,已报道4种有尾类、1个无尾类蝌蚪、1个幼年蜥蜴、3种带原始羽毛的兽脚类恐龙、2种翼龙、3种哺乳动物以及双壳类、叶肢介、昆虫和植物等化石(有学者称之为"前热河生物群")。该层位比热河群义县组低,但地层划分存在争议:中侏罗统九龙山组、上侏罗统道虎沟组和下白垩统热河群均有报道。本文研究的道虎沟蜥蜴是该地点发现的第2个蜥蜴化石,其身体细长,为一幼年个体;前颌骨、顶骨和额骨均成对;上颌骨的面突高;后额骨和后眶骨不愈合;后额骨较大,但可能未进入上颞孔;后眶骨具宽的后突;牙齿小而尖锐,结构简单且可能为侧生;头骨的眶前区较长;具27个荐前椎;虽然未成年但个体较大;未见真皮骨板;手掌和四肢较长。上述特征组合区别于所有现生蜥蜴类,四肢比例也与其他蜥蜴有较大区别。欧美中侏罗世-早白垩世的小盗蜥(Parviraptor)和蒙古早白垩世的一个幼年个体(可能属于壁虎型类)与道虎沟标本比较相似。头骨特征和较大的荐前椎数目显示道虎沟标本可能属于硬舌蜥类(scleroglossan)。但因标本为幼年个体,本文暂将它归入有鳞类属种未定(Squamata gen.et sp.indet.)。测量数据显示,道虎沟标本的手掌和前肢相对较长;该特征常见于适应攀爬的蜥蜴种类,似可显示攀爬习性。但肢体比例可能会随身体增长而发生变化,所以此生活习性并非定论。  相似文献   

11.
Chrysobrycon mojicai sp. nov. is described from forest streams that are part of the Amazon River basin in Colombia. It is distinguished from all congeners by having most of the maxillary teeth with distal tips lateroventrally curved (v. teeth straight along their lengths) and a greater number of dentary teeth (20–27 v. 11–19, except in Chrysobrycon yoliae). The posterior margin of the ventral process of the quadrate does not reach the vertical through the posterior margin of the symplectic and these features differentiate C. mojicai from Chrysobrycon myersi and C. yoliae (v. posterior margin of ventral process of quadrate reaching vertical through posterior margin of symplectic). In species of Chrysobrycon, the frontals are extensively contacting each other along the midline, resulting in an absent frontal fontanel and a reduced parietal fontanel. This extensive contact between the frontals modifying the fontanels is a condition rarely found within the Stevardiinae and hence is proposed as an additional diagnostic characteristic for the genus. An updated identification key for all Chrysobrycon species is provided.  相似文献   

12.
The cranial anatomy of the stem salamander Kokartus honorarius, from the Middle Jurassic of Kyrgyzstan, is redescribed in detail on the basis of all available material using conventional methods and high‐resolution computed microtomography. In contrast to previous interpretations, the skull is characterized by posteriorly positioned external nostrils, the presence of an internarial fenestra between the premaxillae, the maxillae are not shortened, the overlapping of the frontal by the nasal and the parietal by the frontal, a dentate vomer, a dentate pterygoid with a long, strongly arcuate and anteromedially orientated anterior process, the absence of a fontanelle between frontals and pineal pit on the ventral surface of the frontals, and an inferred unique attachment of the adductor mandibulae internus to the lateral border and ventral ridge of the frontals and parietals. Kokartus is closely related to Karaurus and both these taxa constitute the monophyletic taxon Karauridae, which forms the sister group of crown‐group salamanders (Urodela). Karaurids were neotenic forms and neoteny was probably the ancestral life history strategy of salamanders. The morphological analysis of Kokartus supports the current phylogenetic hypothesis that Permian amphibamids (including branchiosaurids) are the closest relatives of salamanders amongst known non‐lissamphibian temnospondyls. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 816–838.  相似文献   

13.
根据一保存完整的骨骼(包括头骨、下颌和全部头后骨骼)建立了鳍龙类的一新属新种——利齿滇东龙(Diandongosaurus acutidentatus gen.et sp.nov.)。标本采自云南省罗平县中三叠世安尼期关岭组上段。新属种既具有肿肋龙类(包括Dactylosaurus,Anarosaurus,Serpianosaurus和Neusticosaurus)吻部两侧不收缩、眶前区域长于眶后区域、眼眶大于上颞孔等典型特征,同时又具有幻龙类(包括Simosaurus和nothosaurians)前颌和下颌前部犬齿型齿发育、上颌具1或2个犬齿型齿等典型特征。新种的额骨和顶骨均愈合,额骨两后外侧支的末端后延超过上颞孔前缘,轭骨和鳞骨相交将眶后骨排除于下颞孔之外,方轭骨发育,锁骨前外侧缘具一突起,3对荐肋以及最前部尾肋的外侧端均未见明显收缩。这些特征也多表现出肿肋龙类和幻龙类的混合特征。此外,新种还具有一些较为独特的特征,包括前额骨和后额骨沿眼眶背缘相交,第3至第8对尾肋的长度超过荐肋,后肢末端发育异常膨大的爪趾骨。系统关系分析表明,滇东龙既不是肿肋龙类也不是幻龙类;它可能与由乌蒙龙、幻龙类和传统的肿肋龙类所构成的分支亲缘关系最近,为始鳍龙类基干类群。  相似文献   

14.
印象初  郑方强  印展 《昆虫学报》2014,57(9):1075-1083
记述了采自中国台湾斑腿蝗科秃蝗亚科1新属台秃蝗属Taipoodisma gen. nov. 和4新种:红股台秃蝗Taipodisma rufifemora sp. nov., 谢氏台秃蝗Taipodisma hsiehi sp. nov., 周氏台秃蝗Taipodisma chowi sp. nov., 黑胫台秃蝗Taipodisma nigritibia sp. nov.。新属台秃蝗属Taipoodisma gen. nov.同蹦蝗属Sinopodisma Chang, 1940近似,不同之处为前胸背板后缘中央缺凹口,中隆线在沟前区不显,在沟后区留有痕迹。新属同辽秃蝗属Liaopodisma Zheng, 1990也近似,不同之处为雄性后胸腹板两侧叶分开,不毗连。新种红股台秃蝗T. rufifemora sp. nov. 后足股节内侧和下方红色可与同属其他种相区别。新种谢氏台秃蝗T. hsiehi sp. nov. 缺黑色眼后带可与同属其他种相区别。新种周氏台秃蝗T. chowi sp. nov. 同红股台秃蝗T. rufifemora sp. nov.近似,不同之处为后足股节内侧和下方非红色。新种黑胫台秃蝗T. nigritibia sp. nov. 同周氏台秃蝗T. chowi sp. nov.近似,不同之处为前胸背板沿中隆线缺黑色纵带和前翅黄褐色,缺黑色带纹。列出了该属的种检索表。  相似文献   

15.
16.
Abstract:  A new pliosaurid, Gallardosaurus iturraldei gen nov. et sp. nov., was found in the Viñales area, western Cuba, in sediments of the Jagua Formation, middle–late Oxfordian. This new taxon is characterized by: wide participation of the premaxilla in the outer margin of the external naris; frontal not participating in the orbital margin; postorbital in contact with the jugal and squamosal; presence of anterior pterygoid vacuity; cultriform process of parasphenoid convex and exposed in palatal view; pterygoid flanges high; jaw articulation low relative to tooth row; trihedral teeth in cross-section and with smooth ridges at least in the labial face. A phylogenetic analysis suggests that Gallardosaurus forms a clade with Peloneustes , the most common pliosaurid genus occurring in the Oxford Clay. The Caribbean Seaway was, at least since the Oxfordian, a corridor that permitted the interchange for marine biota between Western Tethys and Eastern Pacific realms. Among vertebrates, bony fish and long-necked plesiosaurs prevailed. However, marine pleurodiran turtles, metriorhynchid crocodilians, ophthalmosaurian ichthyosaurs, and pliosaurids ( G. iturraldei gen. nov. et sp. nov.) have also been found, as well as at least two species of pterosaurs, and one camarasaurian dinosaur. Among these reptiles there were off-shore pelagic forms such as the ichthyosaurs and metriorhynchids, together with the pliosaurid G. iturraldei gen. nov. et sp. nov.; other taxa were presumably less pelagic, such as the pleurodiran turtles and the cryptoclidid plesiosauroids. Gallardosaurus iturraldei gen. nov. et sp. nov. would have played the role of an active predator taking advantage of nectonic fish recorded in the area.  相似文献   

17.
The new goniopholidid crocodile Goniopholis baryglyphaeus sp. nov. from the Kimmeridgian of Guimarota/Leiria, Portugal is based on the oldest known relatively complete skeleton of Goniopholis from Europe and consists of a nearly complete skull together with a mandible and various postcranial remains. G. baryglyphaeus shows characters that hitherto have only been described for Goniopholis simus : a caudal expansion of the prefrontal that excludes the frontal from the medial margin of the orbit; and the loss of contact between the paroccipital process and the lateral surface of the squamosal and the quadrate, which exposes the cranioquadrate canal laterally. This new species can be distinguished from other European Goniopholis species by an articular facet placed ventral to the retroarticular process, and directed slightly medioventrally; a caudal margin of the mandible forming almost a right angle at its caudoventral corner; an almost square rostrolateral corner of the cranial table; a straight transverse suture between the parietal and the frontal with a median rostral process; a rostrally tapering wedge-like lacrimal, and a regular heavy skull-sculpturing. The new find of Goniopholis in Portugal shows that this genus was distributed in a larger area, and was present much earlier, than hitherto reported in south-western Europe.  相似文献   

18.
本文记述采自新疆南部的裸蝗属Conophyma Zub.二新种.新种“友谊裸蝗”Conophyma amica近似于昭苏裸蝗C.zhaosuensis Huang,以下列特征区别于后者:1)雄性肛上板两后角明显突出,后缘中央锐角形突出;2)后足胫节红褐色.新种“红胫裸蝗”C.rufitibia与C.alajense Misth.相似,其区别为:1)新种雄性尾片显著较大;2)雄性尾须较长,明显长过肛上板后缘中央的突起,3)雌性下产卵瓣下外缘缺一明显的大齿.红胫裸蝗亦近似于C.alamasyi(Kuthy),但可以下述特征区别之:1)雄性肛上板近方形,侧缘中部具一钝瘤状突起;2)雄性腹部背面具二条淡色纵带.模式标本均保存在新疆八一农学院植保系.  相似文献   

19.
Abstract:  The cranial remains of a new Lower Miocene anguimorph, Merkurosaurus ornatus gen. et sp. nov., are described from north-west Bohemia (Czech Republic). The animal is morphologically very similar to the Recent Shinisaurus crocodilurus , but it differs in several ways. The distinctive features of Merkurosaurus are: the nasal process of premaxilla is long and slender with a bilaterally constricted shaft and bilaterally broadened dorsal portion; the dorsal portion of the nasal process divides into three processes of which the median one is the longest; the ornamented surface of the parietal is subdivided into five pustule-like mounds on both right and left sides, with one further mound around the posterior and lateral margins of the parietal foramen. A close phylogenetic affinity to the anguimorph genera Shinisaurus , Bahndwivici , Dalinghosaurus and Carusia , and partially to Xenosaurus , is indicated by characters such as: frontal fused with deep cristae cranii; lateral border of frontals strongly constricted between orbits; double interorbital row of large mounds diverge posteriorly along orbital margin; sculptured postorbital ramus of jugal; small mounds on frontal and parietal with ornamented vermiculate structures; and parietal foramen within parietal but close to anterior margin. Merkurosaurus is the only taxon of this affinity known from the Cenozoic of Eurasia.  相似文献   

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