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1.
Background
The ‘Solnhofen Limestone’ beds of the Southern Franconian Alb, Bavaria, southern Germany, have for centuries yielded important pterosaur specimens, most notably of the genera Pterodactylus and Rhamphorhynchus. Here we describe a new genus of non-pterodactyloid pterosaur based on an extremely well preserved fossil of a young juvenile: Bellubrunnus rothgaengeri (gen. et sp. nov.).Methodology/Principal Findings
The specimen was examined firsthand by all authors. Additional investigation and photography under UV light to reveal details of the bones not easily seen under normal lighting regimes was completed.Conclusions/Significance
This taxon heralds from a newly explored locality that is older than the classic Solnhofen beds. While similar to Rhamphorhynchus, the new taxon differs in the number of teeth, shape of the humerus and femur, and limb proportions. Unlike other derived non-pterodacytyloids, Bellubrunnus lacks elongate chevrons and zygapophyses in the tail, and unlike all other known pterosaurs, the wingtips are curved anteriorly, potentially giving it a unique flight profile. 相似文献2.
Detlev Thies 《Pal?ontologische Zeitschrift》1992,66(1-2):137-146
The diagnosis of the fossil neoselachian genusPalaeospinax Egerton 1872 is revised. A new species from the Lower ToarcianPosidonia Shale of Southern Germany is described asPalaeospinax politus n. sp. It differs from all other known members of the genus in having smooth anterior and lateral teeth. 相似文献
3.
New collections of cestodes from the spiral intestines of catsharks (Carcharhiniformes: Scyliorhinidae) off Taiwan have led to the discovery of a new genus and 2 new species of trypanorhynchs. These taxa are relatively unique among trypanorhynchs in their lack of all elements of the rhyncheal apparatus. The new genus, Nakayacestus n. gen., is considered to belong with Aporhynchus in the Aporhynchidae. In addition to lacking the rhyncheal apparatus, these 2 genera share circum-medullary vitelline follicles, post-ovarian testes, and complex terminal genitalia consisting of accessory, external, and internal seminal vesicles. The 2 genera differ conspicuously in spinithrix configuration; whereas both species of Nakayacestus n. gen. bear scolex spinitriches that are bifid, trifid, or pectinate, species of Aporhynchus either lack scolex spinitriches entirely or possess spathulate spinitriches. The configuration of the bothria of the 2 genera also differ conspicuously. Whereas the bothria of Aporhynchus are sessile and generally do not extend beyond the lateral margins of the cephalic peduncle, those of Nakayacestus bear only a tenuous connection with the scolex proper, being conspicuously free both anteriorly and posteriorly and extending conspicuously beyond the cephalic peduncle. Futhermore, the boundary between the scolex and the strobila of members of the new genus is clearly delineated, whereas this distinction is ill-defined in species of Aporhynchus. Nakayacestus takahashii n. sp., the type of the new genus, was collected from the Broadmouth catshark, Apristurus macrostomus, and differs from Nakayacestus tanyderus n. sp., collected from the Blacktip sawtail catshark, Galeus sauteri, in being shorter, bearing a longer pedunculus scolecis, an ovary that is more posterior in the proglottid, and fewer post-ovarian testes. Furthermore, the 2 new species differ conspicuously from one another in the configuration of their scolex spinitriches. 相似文献
4.
The paleobiology of the Cretaceous neoselachian shark,Squalicorax, has largely been based on isolated teeth. We examined partial and nearly complete skeletons of three species ofSqualicorax, S. falcatus (Aoassiz),S. kaupi (Agassiz), andS. pristodontus (Agassiz), that were collected from the U.S.A. These specimens suggest that the total body length (TL) ofS. falcatus typically measured 1.8–2.0 m, and probably did not exceed 3 m. Moderatesized individuals ofS. kaupi andS. pristodontus perhaps measured about 3 m TL. AlthoughS. pristodontus was the largest form among the three species examined, this taxon possessed a set of large jaws (with large but fewer teeth)
relative to its body size compared toS. falcatus orS. kaupi. This suggests that tooth size is not an accurate indicator of the TL if one compares oneSqualicorax species to another. Neurocranial features suggest that the vision ofSqualicorax was not as acute as that of a contemporaneous macrophagous lamniform shark,Cretoxyrhina mantelli (Agassiz) , but olfaction ofSqualicorax may have been better thanC. mantelli. The morphology of placoid scales suggests thatSqualicorax was capable of fast swimming. New skeletal data support the view that the feeding dynamics ofSqualicorax was similar to the modern tiger shark (Galeocerdo
Müller & Henle). The present data do not allow for exact ordinal placement, but, contrary to some previous interpretations,Squalicorax can be excluded from the Hexanchiformes and Orectolobiformes. The taxon should more appropriately be placed within the Lamniformes
or Carcharhiniformes.
相似文献
5.
Oncoid-dwelling foraminifera from Late Jurassic shallow-water carbonates of the Northern Calcareous Alps (Austria and Germany) 总被引:2,自引:0,他引:2
Oncoidal limestones with different oncoid types are ubiquitous in back-reef open-lagoonal and, to a minor amount, in closed-lagoonal facies of the Late Jurassic Plassen Carbonate Platform of the Northern Calcareous Alps. A common feature of the oncoids from moderately to well-agitated open-lagoonal habitats are incorporated small trochospiral benthic foraminifers, tentatively assigned to trochamminids, switched between individual micritic layers. Their life style is discussed concluding a specialized feeding on cyanophytes on the outer side of the oncoids and later becoming biomurated by successive sheet formations due to oncoid growing. 相似文献
6.
A Belonostomus tenuirostris (Agassiz, 1833) from Late Kimmeridgian (Late Jurassic) of Kelheim (Solnhofen area; Bavaria, southern Germany) that was preserved with three prey fishes in its digestive tract is described. Two of the prey fishes can be assigned to cf. Leptolepides (Orthogonikleithridae), whereas the third possibly represents a juvenile Caturus sp. (Caturidae). This is the first record of a Belonostomus with several prey animals, and the first evidence of a caturid predated by an aspidorhynchid. 相似文献
7.
Cryptocleidus ? cuervoi caroliDE LA TORRE & ROJAS, 1949, a partial skull with associated mandible and atlas-axis from the Oxfordian of Cuba, has been completely prepared for the first time. It is here redescribed and assigned to a new cryptoclidid genus, Vinialesaurus, for which the species caroli is retained. Vinialesaurus is mainly diagnosed by palatal characters such as double internal nares, an anteriorly rounded vomer and a lack of anterior interpterygoid vacuities. It shares with other cryptoclidids large orbits and external nares, a small vertical jugal and a reduced tooth ornamentation. The occurrence of Vinialesaurus caroli in association with pliosauroids, ophthalmosaurian ichthyosaurs, metriorhynchid crocodilians and pleurodiran marine turtles, strongly suggests that a marine seaway was present in the Caribbean during the Oxfordian, connecting the western Tethys with the Oriental Pacific. 相似文献
8.
A new Jurassic species of the very rare and incompletely known synechodontiform shark, Welcommia, is described. The new species, Welcommia cappettai, is represented only by a single tooth, precluding reconstruction of its dentition in detail. Nevertheless, this specimen
provides sufficient information and characteristics to establish its taxonomic status. Welcommia cappettai n. sp. occurs in the middle Oxfordian (Upper Jurassic) of south-western Germany. This is the first unambiguous record and
named species of Welcommia from the Late Jurassic, substantially reducing the rather large gap in the fossil record of this synechodontiform taxon.
So far, two Welcommia species from the Lower Jurassic of Belgium and the Lower Cretaceous of southern France have been described. An additional,
still unnamed species seemingly occurs in the Oxfordian of southern France. The new species has plesiomorphic and apomorphic
characteristics and, probably, an intermediate dental pattern that tentatively enables reconstruction of evolutionary trends
in the dentition of this shark from small and compact teeth with broad, almost triangular cusps, to mesio-distally lengthened
teeth with elongated mesial heels resulting in an extremely extended mesial cutting edge in addition to more delicate cusp
and cusplets in advanced forms. These differences might be related to improved feeding mechanisms. It is hypothesized that
Welcommia was predominantly a component of the Mediterranean faunal province. The disappearance of Welcommia in the Early Cretaceous remains ambiguous and might be related to competition by other sharks, for example hexanchiforms,
or might represent a collecting bias and/or taxonomic misidentification of isolated teeth. 相似文献
9.
Abstract: The exquisitely preserved holotype of the pliosaur ‘Rhomaleosaurus’victor (SMNS 12478) is described from the Toarcian Posidonien‐Schiefer (Upper Lias, Lower Jurassic) of Holzmaden (Baden‐Württemberg), Germany. The specimen presents a novel combination of synapomorphies and unique morphometric proportions separating it from Rhomaleosaurus sensu stricto and warranting the erection of a new genus, Meyerasaurus gen. nov. Historically, the name ‘Thaumatosaurus’ has been interchangeable with Rhomaleosaurus and is frequently associated with SMNS 12478 in the literature. However, this is an invalid taxon and cannot be reinstated. The anatomy of Meyerasaurus victor is compared in detail with other pliosaurs, and its taxonomic affinity is reviewed. M. victor belongs to the family Rhomaleosauridae and shares several anatomical characters with Rhomaleosaurus including a short and robust premaxillary rostrum (length‐to‐width ratio c. 1.0), parallel premaxilla–maxilla sutures anterior to the nares, vomers contacting the maxillae posterior to the internal nares, and c. 28 cervical vertebrae minus the atlas–axis. The known geographical distribution of Rhomaleosaurus, which previously extended across the German and English palaeobiogeographical zones, is reduced to the English zone as a consequence of the referral of SMNS 12478 to a new genus. This is significant because it contributes to an ongoing trend of increasing generic separation between the German and English zones, while increasing the generic diversity within the German zone itself. 相似文献
10.
A low-diversity cockroach assemblage from the Upper Jurassic of the Houtiyn-Hotgor locality in Mongolia is described, comprising Solemnia alexandri gen. et sp. nov. (Caloblattinidae), Blattula choutinensis sp. nov. (Blattulidae) and a presumed Triassic relict Irreblatta relicta gen. et sp. nov. (incertae familiae). The carnivorous Raphidiomimidae supposedly originated directly from the Caloblattinidae. 相似文献
11.
Two new dinosaurs, Kulindapteryx ukureica gen. et sp. nov. (Jeholosauridae) and Daurosaurus olovus gen. et sp. nov. (Hypsilophodontidae) from the Ukureisk Formation (?Tithonian, Upper Jurassic) of the Kulinda locality in Transbaikalia (Russia) are described and assigned to Ornithopoda (Ornithischia). The origin and homology of the so-called obturator process of the ischium of Ornithopoda and Theropoda are discussed. The families Jeholosauridae and Hypsilophodontidae as well as Lesothosauridae are considered to belong to the infraorder Hypsilophodontia (Ornithopoda, Ornithischia). It is shown that hypsilophodontians had skin scales divided into bristles. 相似文献
12.
A new species of an atoposaurid crocodilian, Theriosuchus guimarotae, is described from the Late Jurassic (Kimmeridgian) of Portugal. Theriosuchus guimarotae can be distinguished from other species of Theriosuchus by a lateral surface of squamosal bevelled ventrally; a rounded, caudally projecting and dorsally sculptured caudolateral corner of the squamosal; a premaxillomaxillary suture aligned caudomedially in dorsal aspect; a minimum space between the supratemporal foramina that comprises one third of the total width of the cranial table; a minimum width of the frontal between the orbits that comprises one third of the maximum width of the skull at the orbits; a dentition that comprises only pseudocaniniform and lanceolate-shaped teeth; the presence of an external mandibular fenestra and all vertebral bodies amphicoelous. Its osteology also sheds light on the diagnosis of Theriosuchus within Atoposauridae. The material additionally includes specimens representative of several ontogenetic stages, each of which is discussed here. With its Late Jurassic age, T. guimarotae represents the oldest well-preserved material of Theriosuchus and reveals further knowledge about the palaeobiogeography of the genus in western Europe. 相似文献
13.
A new species of Aspidorhynchidae is described for the first time from the Late Jurassic of Ettling, some 50 km E-SE of Solnhofen, Bavaria, Germany. This new material is attributed to a new species, Aspidorhynchus sanzenbacheri, and is diagnosed by the abbreviated premaxillae, the form and disposition of teeth in the predentary, and the number of principal rays in the caudal fin. 相似文献
14.
DETLEV THIES 《Journal of Zoological Systematics and Evolutionary Research》1987,25(3):188-204
The Hexanchiformes (Cow Sharks) are regarded as a monophyletic taxon. Cladistic analysis shows that among the various neoselachian taxa proposed so far as the sister group of the Hexanchiformes a sister group relationship between the Hexanchiformes and a (still unnamed) taxon comprising the Squaliformes and Pristiophoriformes appears as the most probable hypothesis. In addition, MAISEY and WOLFRAM'S (1984) concept of hexanchiform interrelationships is critically reviewed. An alternative cladogram of hexanchiform interrelationships is developed which includes Recent as well as fossil hexanchiform taxa. In this cladogram the living genera Hexancbus and Notorynchus are sister groups and both taxa together form the sister group of the Recent Heptranchias. The fossil taxa +Notidanoides, +“Hexanchus” gracilis, +Notidanodon and +Weltonia are arranged in the stem lineage of recent Hexanchiformes. 相似文献
15.
Dr. Thomas C. Brachert 《Facies》1992,27(1):191-216
Summary The Late Jurassic epicontinental sea of South Germany protruded far to the North forming a wide bay which was rimmed by shallow-water platforms (Swiss and French Jura). This wide shelf is characterized by extensive downslope mud accumulations including siliceous sponge buildups. The bioherms are aligned along the more pericontinental parts of this shelf, which graded to the South into the Helvetic Basin of the Tethys Ocean. Five sedimentary cycles of Oxfordian to Middle Kimmeridgian age (ox. 2–ox. 3, ki.1.–ki.1.2, ki.3, ki.1.3–ki.2.1, ki. 2.1–ki. 2.2) were used for interregional correlation. Each cycle is characterized by a vertical suite from marl to pure limestone. The bases of the marls are characterized by abundant open-marine fossils, glauconite and phosphate (fish teeth and pellets) and interpreted as condensed sections. Deepening is indicated by bioherms changing their growth form before demise from large structures into small isolated buildups, which commonly occur within deeper water. Sequence boundaries, are present at the transition from marl into limestone. Two phases (middle ki. 1.3 and ki. 1/2) of debris-flow deposition, one accompanied by the sudden spreadout of biostromes and basinward shift of bioherms, are interpreted as lowstand phases associated with sequence boundaries. The remaining sedimentary cycles described here lack such lowstand deposits. Instead, corresponding positions in the cycles are characterized by omission features. This problem is still unresolved. It may either be due to sediment trapping on the ramp or to a changing origin of the cycles compared. It is proposed here that highstand sediments, having higher contents of fine-grained siliciclastics than lowstand deposits, formed during a humid and warm climate with high rates of continued runoff and sediment transport. Lowstand deposits consist of pure offbank carbonates, because the associated drier climate reduced fluvial input of terrigenous material. Corresponding patterns of climatic change are also seen in platform sediments from the Swiss Jura Range; however, climatic cycles correlate with eustatic sea level fluctuations in only about 50% of the cases. This misfit may partially result from problems with biostratigraphic correlation (boreal— Tethyan). Small-scale sedimentary cycles with an average duration of 66’000 years (Mutabilis chron, ki. 2) to 95’000 years (Planula chron, ox. 3) provide a tool for detailed stratigraphic correlation in biostromes, small scale lenticular bioherms (1–2 m thickness) and large bedded bioherms (many tens of metres thickness). Interruptions of bioherm growth are due to temporal oxygen deficiency related to plankton blooms. The bathymetrically deepest bioherms-small and lenticular in shape—therefore suffered the highest number of ecological break-downs, whereas massive bioherms continuously remained above the critical level. 相似文献
16.
17.
E. D. Lukashevich 《Paleontological Journal》2011,45(6):620-628
New nematoceran taxa are described based on isolated wings from the Late Jurassic Shar Teg locality (Mongolia): ?Nannotanyderus incertus sp. nov. (Tanyderidae), Crenoptychoptera liturata sp. nov. (Ptychopteridae), Chaoburmus amphilogos sp. nov., Mesocorethra cincta sp. nov. (Chaoboridae), Rasnicynomma additum gen. et sp. nov., and Palaeoperissomma ornatum sp. nov. (Perissommatidae). 相似文献
18.
V. R. Alifanov S. V. Saveliev E. Yu. Tereshchenko V. V. Artemov A. Yu. Seregin 《Paleontological Journal》2014,48(5):523-533
Integumentary structures of ornithischain dinosaurs of the taxon Hypsilophodontia (Ornithopoda) from the Ukureiskaya Formation (Upper Jurassic) of the Kulinda locality (Transbaikal Region, Russia) are described in detail. It is shown that members of this group had so-called bristle scales, integumentary appendages previously unknown in ornithischian dinosaurs. These are relatively small horn plates embedded in the skin, the distal margin of which has several long, flat, and probably constantly growing bristles. The monobristle variant of bristle scale is probably homologous to the protofeather of theropods; if this is the case, it is possible to reconstruct the protofeather as an elongated and constantly growing scale. 相似文献
19.
Thomas Martin 《Journal of Mammalian Evolution》1997,4(1):1-18
The discovery of juvenile dentitions of late Jurassic (Kimmeridgian) Dryolestidae (Eupantotheria, Mammalia) from Guimarota, Portugal, yields for the first time information on the mode of tooth replacement in therian mammals prior to the dichotomy of placentals and marsupials. As in extant placentals, tooth replacement occurs at all antemolar positions [incisors (I1–I4), canine (C), premolars (P1–P4)]. P1 and P2 have premolariform milk predecessors, whereas the large premolariform third (P3) and fourth premolars (P4) are preceded by molariform deciduous premolars (dP3, dP4). Tooth replacement takes place in two waves, at least in the lower jaw, with I2, I4, P1, and P3 in the first series and I1, I3, C, P2, and P4 in the second. P4 is the last premolar to erupt, and it is present when the sixth molar (M6) starts to break through. The reduced tooth replacement pattern of marsupials (with only dP3 being replaced postnatally) evolved secondarily from the primitive or plesiomorphic mammalian condition, which was retained in Dryolestidae and Eutheria. 相似文献
20.
The fishes of the genus Aspidorhynchus (Aspidorhynchidae) are among the most abundant predators in the palaeolagoons of the Solnhofen archipelago (Late Jurassic, southern Germany). They have been known since the end to the nineteenth century and the last revision of the genus was published more than 20 years ago. During these last two decades, numerous complete and excellently preserved specimens have been collected. The high morphological diversity shown by the new material made a new revision of these fishes necessary. This new taxonomic revision led us to revalidate the species A. ornatissimus Agassiz, 1834, which has hitherto been considered a junior synonym of the type species of the genus, A. acutirostris (Blainville, 1818), as well as to recognize high intraspecific variation in the latter species. These results helped to improve the distinction and, thus, the diagnoses of A. acutirostris, A. ornatissimus, and A. sanzenbacheri Brito and Ebert, 2009, which are the three valid species of this genus in the Solnhofen archipelago. We have been able to explain most of the intraspecific diversity of A. acutirostris by means of patterns of ontogenetic variation that encompass most of the other nominal species, thus largely reflecting early taxonomic hypotheses. Furthermore, the detailed morphological study led us to the recognition of some important anatomical structures previously unknown for aspidorhynchids: a connection between the temporal, infraorbital and supraorbital sensory canals in the frontal bone, the presence of an Y-shaped antorbital bone, and the presence of an interoperculum. 相似文献