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1.
根据新材料,对始无齿翼龙的特征进行了修订:中部颈椎体没有神经棘;肱骨三角嵴的长度与肱骨长度之比率约为0.25;翼掌骨的长度与第二翼指骨的长度几乎相等;第二翼指骨与第一翼指骨的长度之比率约为0.76.始无齿翼龙的新标本与正型稍微不同,可能由个体发育所引起.  相似文献   

2.
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   

3.
A new baby pterodactyloid pterosaur with soft tissue preserved, Ningchengopterus liuae gen. et sp. nov., is erected based on a nearly complete skeleton with a skull. It was characterized by the skull, slightly longer than the combined length of the dorsal and sacral vertebrae; 50 teeth (including upper and lower jaws); short mid-cervical vertebrae; the humerus and the scapula, equal to that of the wing metacarpal in length; the ulna and the femur, equal to that of the first and third wing phalanx in length, respectively. The similar ratio of the wing phalanx 2 to wing phalanx 1 of Ningchengopterus and Eosipterus implies that Ningchengopterus may be close to the ctenochasmatid pterosaur. However, it may also imply that the isometrically growing of the first two wing phalanges exists among some pterosaurs.  相似文献   

4.
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   

5.
Two new genera and species of fossil Palaeontinidae are described from Daohugou Village, Inner Mongolia, China: Cladocossus undulatus gen. et sp. nov. and Cricocossus paradoxus gen. et sp. nov. Both new genera are described based on well-preserved forewings. This discovery confirms the high diversity of palaeontinids during the Middle Jurassic. Both specimens have interesting modal structures which are new to Palaeontinidae: M five-branched and M3 with two branches. Based on this character, wing structural characteristic is discussed.  相似文献   

6.
A new basal non-pterodactyloid pterosaur,Changchengopterus pani gen.et sp.nov.,is erected,on the basis of a nearly complete postcranial skeleton.The new taxon is distinguished by relatively short extensions of the prezygapophyses,postzygapophyses and haemal arches of the caudal vertebrae;a humerus that has a subtriangular deltopectoral crest;limb elements that decrease in length in the following order:ulna>wing-phalange 2>wing-phalange 3=wing-phalange 1>humerus>tibia>femur>wing-metacarpal.Phylogenetic an...  相似文献   

7.
<正>Juraperla grandis sp.nov.(Grylloblattida:Juraperlidae) is described from the Daohugou locality (Middle Jurassic,China).Its wing venation is very similar to that of Juraperla daohugouensis Huang and Nel,2007 (Grylloblattida:Juraperlidae),in the particular occurrence of a supplementary longitudinal vein in the area between the anterior wing margin and ScP.The larger size of the new specimen,the lower number of CuA1 branches,and the occurrence of two rows of cells between MP and CuA in forewings justify the erection of a new species,J.grandis sp.nov..The material also preserved hind wing and body structures,described for the first time in Juraperlidae.  相似文献   

8.
记辽宁一新翼龙化石（喙嘴龙亚目）   总被引：21，自引：0，他引：21  
姬书安  季强 《江苏地质》1998,22(4):199-206
记述了辽宁北票四合屯炒米甸子组中一新翼龙化石,该翼龙个体极小,两翼展开仅约４０ｃｍ。化石具有同形齿、长尾、极短的翼掌骨和非常发育的后肢第Ⅴ趾等特征,因而无疑可归入喙嘴龙亚目喙嘴龙科（Ｒｈａｍｐｈｏｒｈｙｎｃｈｉｄａｅ）,并代表一新属种弯齿树翼龙（Ｄｅｎｄｒｏｒｈｙｎｃｈｕｓｃｕｒｖｉｄｅｎ－ｔａｔｕｓｇｅｎ．ｅｔｓｐ．ｎｏｖ．）。该化石是我国及东亚晚侏罗世喙嘴龙类翼龙的首次记录,它的发现有力地表明包括中华龙鸟和孔子鸟在内的辽西四合屯化石层的地质时代应为晚侏罗世。  相似文献   

9.
The family Mesopsychidae Tillyard,1917 presently consists of ten described genera from the Early Permian to the Early Cretaceous of Australia,China,Kyrgyzstan,Russia,South Africa,Tajikistan,and Ukraine.Herein,a new genus and a new species of fossil mesopsychid,Epicharmesopsyche pentavenulosa gen.et sp.nov.,is described from the Middle Jurassic Jiulongshan Formation of Inner Mongolia,China,supplementing the family-level diversity.The well-preserved,new material reveals many characters,including antennae,wing venation,shape and genitalia that increase our morphological understanding of the family,although unfortunately the mouthparts and most of the legs are not preserved.Diagnosis of the Mesopsychidae is emended to include a four-or five-branched MP in both the fore-and hind wings.This is the first documentation of a wing coupling structure in the Mesopsychidae,consisting of three to four frenula bristles on the humeral lobe at the base of the costal margin of both hind wings.Asymmetrical shape and size of the left and right wings on a specimen of E.pentavenulosa gen.et sp.nov.,seems to be a common condition for mesopsychid taxa from northeastern China.  相似文献   

10.
A New Family of Moths from the Middle Jurassic (Insecta: Lepidoptera)   总被引：1，自引：1，他引：0  
<正>Three lepidopteran species,from the Middle Jurassic Daohugou beds(inner Mongolia,China),are described in a new family,Mesokristenseniidae,and new genus,Mesokristensenia,which could represent the sister group of the Micropterigidae.Mesokristensenia differs from all extant Lepidoptera,but one genus(Agathiphaga, Agathiphagidae),in retaining four median veins in the forewing,a plesiomorphy also present in many Trichoptera. Evidence for placing Mesokristensenia in the Lepidoptera includes four traits,notably a previously unrecorded autapomorphy of this insect order:beyond stem M1+2,vein M1 is bent and connected to cross-vein r-m(in both wing pairs).Among 24 characters taken into account to assess the systematic position of Mesokristensenia,12 are considered informative for a cladistic analysis involving this fossil taxon and the four suborders recognized in present-day Lepidoptera(Zeugloptera,Aglossata,Heterobathmiina,and Glossata).  相似文献   

11.
Cretornis hlavaci Frič, 1881 from the Upper Cretaceous (Turonian) of Czech Republic is a valid taxon referred to Azhdarchoidea based on having a saddle-shaped humeral head, pneumatic foramen on proximal humerus present on anterior side and absent on posterior side, elongate deltopectoral crest with subparallel proximal and distal margins, pneumatic foramen absent on distal side of humerus, metacarpals I–III not articulated with carpus and displaced on anterodorsal side of wing metacarpal, and wing metacarpal much longer than humerus. Absence of a pneumatic foramen on posterior side of proximal humerus suggests attribution of Cretornis hlavaci to Neoazhdarchia. It has a unique construction of the distal ulna with a dorsal articulation surface placed distinctly proximal to the tuberculum shared only with the non-azhdarchid azhdarchoid Montanazhdarcho minor from the Campanian of North America. Cretornis hlavaci differs from the latter taxon by the structure of its humerus and distinctly longer wing metacarpal. It is more derived than “Tapejaridae” but shares with Azhdarchidae the deltopectoral crest of the humerus displaced distally from humeral head. Cretornis cannot be assigned to Azhdarchidae because of the oval cross section of the second wing phalanx. A unique rhombic outline of the distal humerus of Cretornis hlavaci is a possible autapomorphy for this taxon. Its wing span estimated as 1.5–1.6 m. This is the first taxon of non-azhdarchid pterosaurs known from the Upper Cretaceous of the Eastern Hemisphere.  相似文献   

12.
The Bittacidae (hangingflies) were abundant and widespread during the Mesozoic, but much of their diversity falls within the Jurassic whereas in the Cretaceous they are less common. A new bittacid, Burmobittacus jarzembowskii gen. et. sp. nov., is described from mid-Cretaceous amber from northern Myanmar. This new find is the first bittacid from Burmese amber and also the first Mesozoic bittacid preserved in amber. The new genus is distinguished from all known bittacids in having a long and narrow wing with Rs arising from R and forking very early (in the basal one-fourth of the wing), resulting in the stem of Rs being very short (about 1/8th of the length of Rs1+2), and stems of the main branches of Rs (Rs1+2 and Rs3+4) being unusually long.  相似文献   

13.
While pterosaurs occur in the Lower Jurassic strata of Britain and Germany, only the family Rhamphorhynchidae is currently known found in both. A newly discovered humerus from the Whitby Mudstone Formation of Lincolnshire challenges this and is distinguished from all other Lower Jurassic British pterosaurs by its possession of a quadrangular deltopectoral crest. This is a rare morphotype which only occurs in Eudimorphodon, Austriadraco, Raeticodactylus, Carniadactylus and Campylognathoides. The Lincolnshire humerus compares well with these taxa but is identified as a cf. Campylognathoides sp. based on its age and palaeobiogeography. The genus Campylognathoides is a common pterosaur in the Toarcian Posidonia Shale of Germany and the new humerus supports continuity of pterosaur populations across central Laurasia.  相似文献   

14.
<正>A new dinosaur Chuxiongosaurus lufengensis gen.et sp.nov.is erected based on a nearly complete skull.The taxon is characterized by the lacrimal perpendicular to the ventral margin of the upper jaw,which is similar to that of Thecodontosaurus;a depression present on the dorsal profile of the snout behind the naris;the rostral profile of the maxilla slopes continuously towards the rostral tip;and the presence of 25 dentary teeth.It also displays prosauropod characters such as a relatively long skull,the slope of the maxillary rostral profile,and teeth that do not have basically constricted crowns.The new specimen is more basal than Anchisaurus and represents the first basal sauropod dinosaur from the Early Jurassic of China.  相似文献   

15.
<正>A new boreopterid pterosaur:Zhenyuanopterus longirostris gen.et sp.nov.from the Yixian Formation of western Liaoning is erected,based on the complete skeleton with a skull and lower jaws preserved.It is characterized by:a large boreopterid pterosaur with a high number of teeth,where the anterior teeth are much larger than posterior ones;the length of the dorsal + sacral vertebrae is nearly half the length of the skull;ratio of the length of the humerus to metacarpal IV is approximately 91%and the,humerus,femur and third wing phalanx are all equal in length and the feet are specially small.It represents the largest boroepterid pterosaur discovered from western Liaoning and its surrounding areas so far  相似文献   

16.
The neuroanatomy of the mid-sized theropod Sinosaurus triassicus from the Lower Jurassic Lufeng Formation, Lufeng Basin in Yunnan Province, China was studied using X-ray computed tomography. The braincase is characterized by a large supraoccipital knob that is capped by a posterior projection of the parietal and two external foramina for the caudal middle cerebral vein, which is completely enclosed by the supraoccipital. The basicranium has well defined, short basipterygoid processes that project ventral to the basal tubera. The basisphenoid is expanded, projects posteroventrally, and is pierced by four pneumatic recesses. The endocranial morphology resembles that observed in other basal theropods—in particular some allosauroids—and has a strongly marked pontine flexure and a large dorsal expansion. The inner ear morphology is also similar to that observed in other basal theropods, with slender semicircular canals. The anterior semicircular canal is 20% larger than the posterior semicircular canal, and the angle formed between them is less than 90° when seen in dorsal view.  相似文献   

17.
Based on an almost complete three-dimensionally preserved skeleton, a new genus and species of an azhdarchoid pterosaur Aurorazhdarcho primordius n.gen. n.sp. from the Late Jurassic Solnhofen limestone (Early Tithonian) of the Eichstätt area (Bavaria, Germany) is described. Furthermore, a new family the Protazhdarchidae is proposed. The specimen is attributed to the Azhdarchoidea based on its glenoid fossa level with the sternum, the shovel-like shape of the sternal plate, the wide furca of the coracoid, the metacarpus being longer than radius and ulna, the femur being 1/3 longer than the humerus, the femorotibial ratio, and the hammer-shaped humerus among other diagnostic features. Under UV-light, soft tissue preservation around the external mould of the head is visible. It consists of tiny flakes possibly remnants of skin. The dorsally curved outline of the external mould of the head suggests the presence of a cranial crest. The new species is the oldest record of the azhdarchoid pterosaurs. It supports the Eurasian origin of this group that includes the largest flying animal ever.  相似文献   

18.
Abstract

The Gangdese batholith, Tibet, records the opening and closing of the Neo-Tethyan ocean and the resultant collision between the Indian and Eurasian plates. The Mesozoic magmatic rocks play a crucial role in understanding the formation and evolution of the Neo-Tethyan tectonic realm. This study focuses on Jurassic intrusive rocks in the Xietongmen area of the southern margin of the Lhasa terrane adjacent to the Yarlung–Tsangpo suture. Zircon U–Pb dating yielded Middle Jurassic dates for ca 170?Ma hornblende gabbro and ca 173?Ma granodiorite intrusions. All of the samples are medium- to high-K calc-alkaline, and the majority are metaluminous and enriched in the large ion lithophile elements and depleted in the high-field-strength elements. This indicates the magma was generated in a subduction-related tectonic setting. The intrusive rocks have high and positive εHf(t) values (hornblende gabbro: 13.3–18.7; granodiorite: 14.2–17.6) that yield Hf model ages younger than 312?Ma. These new data, combined with the results of previous research, suggest that the Jurassic igneous rocks were derived from a metasomatised region of an asthenospheric mantle wedge. Extremely depleted Sr–Nd–Pb–Hf isotope compositions are similar to the Yarlung ophiolite and igneous rocks within other intra-oceanic island arcs. Together with the existence of sandstone that is identified as the product of the oceanic island arc environment, we suggest formation in an intra-oceanic island arc.

  1. The new zircon U–Pb dating has yielded Middle Jurassic ages for the ca 170?Ma hornblende gabbro and ca 173?Ma granodiorite phases of the Xietongmen intrusion.

  2. Jurassic igneous rocks formed from a metasomatised asthenospheric mantle wedge by northward subduction of the Neo-Tethys oceanic crust beneath the southern margin of the Lhasa terrane.

  3. Late Triassic–Jurassic igneous rocks, which are characterised by highly depleted isotopic compositions within the Southern Lhasa sub-terrane, record residual intra-oceanic island arcs in the eastern Tethyan belt.

  相似文献   

19.
More than 30 forewings of Mesoblattina vitimica n. sp. were examined for variation in number and distribution of veins. Considerable variation in the R system between the number of simple branches running towards the anterior margin of the wing, and the number of apical branches is present, but the total number of branches in the system is relatively constant. The number of stems into which the principal vein of the M 'system divides is more constant than the number of branches of this system emerging at the wing margin. The least variable characters are therefore the most reliable for systematics. Comparisons are made with other Jurassic and Cretaceous species of Mesoblattina. — C. R. Palmer.  相似文献   

20.
<正>The classification and phytogeny of the basal Vespina(=Orussoidea+Apocrita)are reconsidered based primarily on rich and well preserved material from the Middle Jurassic of Daohugou in Inner Mongolia,China. Comparatively smooth morphological transitions are traced from a Xiphydriidae-like ancestor toward Orussoidea via the Jurassic family Karatavitidae,and through Karatavitidae and the Jurassic and Early Cretaceous family Ephialtitidae independently to Stephanidae,to Evanioidea,and,via the extinct Jurassic Kuafuidae fam.nov.to the remaining Apocrita.New hypothesis is proposed concerning development of the characteristic wasp-waist of Apocrita,which is supposed to appear independently and in different ways in Evanioidea and in the rest of Apocrita.As a result,six infraorders are proposed for the suborder Vespina with the following taxonomic structure:infraorder Orussomorpha including the only superfamily Orussoidea(Karatavitidae+Paroryssidae + Orussidae),infraorder Stephanomorpha with the only superfamily Stephanoidea(Ephialtitidae+Stephanidae), infraorder Evaniomorpha with the only superfamily Evanioidea of traditional composition,infraorder Ceraphronomorpha with the superfamilies Ceraphronoidea s.str.and monotypical Megalyroidea and Trigonaloidea,and the infraorders Proctotrupomorpha,Ichneumonomorpha,and Vespomorpha of traditional composition.The family Kuafuidae is unplaced to infraorder because it is putatively paraphyletic with respect to Ceraphronomorpha,Proctotrupomorpha,Ichneumonomorpha and Vespomorpha.Described as new are Karatavites junfengi sp.nov,Praeratavites wuhuaensis sp.nov.,P.perspicuus sp.nov.,Postxiphydria daohugouensis gen.et sp.nov.,P.ningchengensis gen.et sp.nov.,Postxiphydroides strenuus gen.et sp.nov.,Praeratavitoides amabilis gen.et sp.nov.,Proapocrtius densipediculus sp.nov.,P.sculptus sp.nov.,P.longantennatus sp.nov., P.formosus sp.nov.,P.atropus sp.nov.,P.elegans sp.nov.,Stephanogaster pristinus sp.nov.,Asiephialtites lini sp. nov.,Praeproapocritus vulgatus gen.et sp.nov.,Sinaulacogastrinus solidus gen.et sp.nov.,Sinevania speciosa gen. et sp.nov.,Eonevania robusta gen.et sp.nov.,Kuafua polyneura gen.et sp.nov.(all from the Middle Jurassic of Daohugou),as well as Kuafuidae fam.nov.including Kuafua gen.nov.as well as Arthrogaster Rasnitsyn,1975,and Leptogastrella Rasnitsyn,1975 from the Upper Jurassic of Karatau in Kazakhstan.  相似文献   

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