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1.
Ammonites bidentosus Quenstedt from theplatynotazone of the Lower Kimmeridgian (Upper Jurassic) belongs to the genusCymaceras. Its peculiarities can be explained by neoteny. Although the species is a microconch, there is no proof of sexual dimorphism. The species is known from southern Germany and northern Switzerland. It is always rare. Most specimens are linked with the sponge-algal facies.  相似文献   

2.
Three species of Palaeoneilo Hall & Whitfield, namely P.belaeensis Cox, P. indicus Cox and P. rajnathi n. sp., are describedfrom the Jurassic rocks of Habo Hill in Kutch. The right, valveof belaeensis has been discovered. Its previous record fromthe Bathonian (Middle Jurassic) appears to be erroneous. Bothbelaeensis and indicus were unknown from the present area. (Received 11 November 1983;  相似文献   

3.
Jurassic strata of late Oxfordian to early Kimmeridgian age are reported from the Cerro Pozo Serna, northwest-central Sonora, Mexico. The presence of these marine strata greatly alters previous paleogeographic reconstructions of the Tethyan embayment in this area. Approximately 60% of the Sonorian molluscan fauna has been previously reported from Jurassic horizons in the Gulf of Mexico and west Texas regions. The remainder of the molluscs have previously been reported from either the western interior United States or Canada. The Pozo Serna faunas seem to be zoogeographically transitional between communities present in the southern North American Tethyan realm and regions within the central North American Tethyan realm. Additionally, the Pozo Serna fauna greatly resembles contemporaneous communities reported from the Jurassic of Morocco. Corals from the Sonorian Jurassic prove to be, in large part, conspecific with well-known central European and Algerian reef-building species. The scleractinian Lepidophylliopsis gen. nov. and Macgeopsis sonorensis sp. nov. are described from central Sonora.  相似文献   

4.
Two species of fossil insects from the Daohugou Formation of Chifeng City in Nei Monggol Autonomous Region, northeastern China are described, and recognized as Psocites pectinatus (Hong, 1983) nov. emend., nov. transl. and P. fossilis nov. sp. They are the oldest representatives of the family Callovian or Axymyiidae, and first described of this family in the Mesozoic. Although early the age of the fly-bearing beds is controversial, it is probably Oxfordian or Kimmeridgian (Late Jurassic) rather than Early Cretaceous or Middle Jurassic.  相似文献   

5.
6.
《Geobios》1988,21(6):741-748
A large ammonite has been found in the predominantly non-marine Lastres Fm. at Villaviciosa, Asturias, Northern Spain. It is identified as Eurasenia sp. aff. manicata (Schneid), indicating an Upper Jurassic age, late Lower Kimmeridgian sensu gallico. This is the earliest record in the Upper Jurassic of the northern margin of the Iberian sub-plate. The sedimentary sequence indicates a regime of small and fluvially-dominated near-shore delta systems subjected to episodic marine ingressions.  相似文献   

7.
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   

8.
9.
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   

10.
Abstract: Astacidean and thalassinidean macrurans (Glyphea sp., ?Eryma sp. and Protaxius sp.) and a new longodromitid crab, Planoprosopon kashimaensis, are recorded from the Upper Jurassic (upper Kimmeridgian to lower Tithonian) of Fukushima Prefecture, northeast Japan. Material was collected from the Tatenosawa Sandstone Member of the Nakanosawa Formation, Somanakamura Group, from which abundant Tethyan‐type marine invertebrates are known. Planoprosopon kashimaensis sp. nov. closely resembles P. heydeni (von Meyer), a common form in the Upper Jurassic of the Tethyan realm in Europe, and represents the oldest record of a brachyuran from the circum‐Pacific region. Similarities to contemporaneous decapod assemblages in southern Germany indicate that closely comparable, parallel decapod faunas in the Tethyan realm, inclusive of brachyurans, had already been established in the western circum‐Pacific region by the Late Jurassic.  相似文献   

11.
The genus Anopaea represents a small but distinctive group ofinoceramid bivalves that apparently remained functionally endobyssate.The somewhat unusual morphology (for an inoceramid) probablyresults from structural modifications tofacilitate sedimentpenetration at a high angle and anchorage by an antero-ventralbyssus. Although never as common as thecontemporary genera Retroceramusand Inoceramus, Anopaea is now known from temperate bivalveassemblages in both the Northern and Southern Hemispheres. Itpersisted from the Late Jurassic (Tithonian) to the Early Cretaceous(Neocomian), and possibly even later. (Received 26 June 1980;  相似文献   

12.
In the framework of the palaeogeographical reconstruction of the Western Taurus during Jurassic, the study of northern and eastern boundary of the Taurids started. Detailed facies analysis evidenced the position of the Barla Dag ramp between two elevated areas: the southern rimmed shelf extension of the platform system and the northern neritic-beach-land plain. In the basal biostratigraphical and ecological characteristics of the Balcikhisar volcano-sedimentary sequence, correlated with the Fele outcrop, one genus and three new species of foraminifers have been found: Sievoides kocyigiti n. gen., n. sp. and Mesoendothyra altineriana n. sp. from neritic environment, and Kurnubia feleensis n. sp. from rimmed shelf lagoon. Both carbonate sedimentary deposits are intercalated with spilitic-basalt pillow lava flows. The age of the new three species is Kimmeridgian, controlled by some foraminifer golden hooks.  相似文献   

13.
《Geobios》2016,49(5):355-364
A juvenile turtle from the upper Kimmeridgian (Upper Jurassic) of Nusplingen is identified as an eurysternid turtle. It differs in plastral morphology from a juvenile eurysternid turtle from the latest Kimmerdigian of Kelheim described in the 19th century, which represents a comparably early developmental stage. Both juveniles have primordial ribs not yet transformed into costals and lack all other carapacial elements whereas the plastral elements are well developed. The new specimen from Nusplingen has a more robust plastron type when compared to the very gracile, bow- or arc-shaped plastron type of the formerly described juvenile. Both plastron types are also represented by yet undescribed additional juvenile, medium-sized and/or larger eurysternid specimens. The juvenile specimens thus likely document the presence of two morphologically very similar eurysternid taxa in the Upper Jurassic of southern Germany. Both plastron types are different from those described for Idiochelys and Solnhofia but may resemble plastron morphology of Eurysternum, which is, however, only incompletely known.  相似文献   

14.
Klug, C., Schweigert, G., Fuchs, D. & Dietl, G. 2009: First record of a belemnite preserved with beaks, arms and ink sac from the Nusplingen Lithographic Limestone (Kimmeridgian, SW Germany). Lethaia, 10.1111/j.1502‐3931.2009.00203.x A recent discovery of an unusually preserved belemnite from Nusplingen comprises the extraordinarily rare remains of beaks and nearly in situ arm hooks, as well as the ink sac and an incomplete phragmocone. So far, Hibolithes semisulcatus ( Münster, 1830 ) is the only belemnite known from the Nusplingen Lithographic Limestone (Upper Jurassic, Late Kimmeridgian, Beckeri Zone, Ulmense Subzone; SW Germany) that has the same phragmocone shape and size, and thus we assign the new specimen to this taxon. The rostrum was probably lost due to a lethal predation attempt in which the prey was killed but not entirely eaten. For the first time a specimen reveals details of the belemnite beak morphology, which we compare with the beaks of other Jurassic coleoids. This specimen presently represents the only known rostrum‐bearing belemnite of post‐Toarcian age with preserved non‐mineralized body parts. With the new discovery, Nusplingen now represents the only locality which has yielded complete beak apparatuses from all major Jurassic cephalopod groups. □Beaks, Belemnitida, Coleoidea, Germany, Late Jurassic, morphology, taphonomy.  相似文献   

15.
The Kimmeridgian Series situated at the North ofLisbon is included in the Portuguese Lusitanian basin. Its sandy clays pelagic facies with planctonic foraminifera contains a new species of bivalvia: Aulacomyella abadiensis related to A. neogeaeImlay from the Middle Kimmeridgian of Mexico and from the Kimmeridgian of Crimea. This species confirms the Middle Kimmeridgian.  相似文献   

16.
The anatomy of Cornirostra (new genus) pellucida (Laseron),a marine Indo-West Pacific gastropod, is described and is shownto be similar to that of the northern hemisphere, freshwaterValvatidae. There are, however, several differences betweenCornirostra and valvatids, notably in details of the anatomyof the reproductive system, the morphology of the head-foot,the spawn and in radular characters that warrant family-levelseparation for Cornirostra. Tomura bicaudata (Pilsbry and McGinty) from Florida is alsoa member of the family. (Received 9 September 1989; accepted 30 December 1989)  相似文献   

17.
Sampling of a lenticular concentration of vertebrate debris and associated sediments from the lower Kimmeridgian of southern England has allowed the study of a diverse and abundant assemblage of chondrichthyan remains. A number of previously undescribed species are recorded, of which three new species are named; Squatina? frequens, Synechodus plicatus and Protospinax planus. Additional diagnosis of the genus Paracestracion Koken is given to allow its identification from dental remains. Several nominal batoid species are synonymised with Spathobatis bugesiacus Thiolliere. This assemblage is considered to be typical of Middle–Late Jurassic neritic environments, and is compared to other contemporaneous selachian faunas.  相似文献   

18.
Species of Saccostrea are common oysters on Indo-Pacific rockyshores. The taxonomy of this genus is unclear, however, becauseof morphological plasticity among its constituent species. Oystersamples with distinct morphotypes were collected from shoresexperiencing different degrees of wave exposure in Japan, Taiwan,China, Vietnam, Singapore and Australia. Intraspecific and interspecificvariations in shell characters have been identified. Only S.kegaki could be readily differentiated from S. cucullata-B,S. cucullata-C and S. mordax by multivariate shell allometricanalyses. Phylogenetic analyses using partial mitochondrial16S DNA sequences of approximately 513 base pairs identifiedtwo clades that correspond to superspecies, i.e. putative S.cucullata and putative S. mordax, comprising nine and two lineagesfrom the Indo-West Pacific, respectively. These are S. cucullata-A,B, C, D, E, F, G, S. kegaki and S. glomerata in one clade, andS. mordax-A and B in the other. Interspecific sequence divergence(Kimura-2-parameter values) between lineages ranged from 1.02%to 11.74%. Both S. cucullata-C and S. kegaki are restrictedto the northern hemisphere, whereas S. glomerata seems to bea temperate species from the southern hemisphere. S. cucullata-Doccurs only in Taiwan. Other species, i.e. S. cucullata-A, B,D, E and F and S. mordax-A and B, have a wide range on rockyshores in the tropical and subtropical Western Pacific and inboth northern and southern hemispheres. (Received 7 January 2005; accepted 4 November 2005)  相似文献   

19.
The anatomy of Pachydermia laevis Warén & Bouchet,1989 is investigated. It is a deep-sea gastropod and restrictedto hydrothermal vents of the East Pacific Rise. Its anatomyresembles that of Melanodrymia aurantiaca Hickman, 1984 (Melanodrymiidae)in most respects, except that its gonopericardial duct opensinto the renopericardial duct, not into the peri-cardial chamber,and that it lacks a copulatory organ. Examination of M. aurantiacamain confirms earlier work. The two species have a cerebralbuccal connective fused with the cerebral ganglion (not freefrom it), a synapomorphy that has not been described for anyother archaeogastropod. The investigation suggests that Melanodrymiaand Pachydermia are closely related and together with Cyathermiidaeand Neomphalidae form a monophyletic group within the Neomphalina.No evidence was found to support earlier speculations aboutclose relations of Neomphalina to Viviparoidea. (Received 10 January 1996; accepted 3 April 1997)  相似文献   

20.
Upper Jurassic (Kimmeridgian) limestones of central Poland (southern border of the ?ód? Depression) are in places extremely rich in crinoid remains. These latter are represented by very well preserved columnals/pluri-columnals, isolated brachials and cirrals/pluri-cirrals, assignable to the following species: Isocrinus amblyscalaris (Thurmann, in Thurmann and Éttalon), Isocrinus cf. pendulus (von Meyer), Balanocrinus brachiospina Hess, Balanocrinus pentagonalis (Goldfuss), Balanocrinus subteres (Münster, in Goldfuss), Balanocrinus sp., and Millericrinida indet. The commonest species, Balanocrinus brachiospina, is recorded for the first time from Poland. Critical revision of Polish occurrence of balanocrinids is provided. It is suggested that some of the previous balanocrinid finds from Poland assigned to Balanocrinus subteres should be now addressed as Bbrachiospina. Furthermore, it is probable that the Callovian Bhessi Salamon and Zatoń should be synonymized with Bpentagonalis. Crinoid material at hand is also associated with asteroid and echinoid remains. Among this material, a complete test of Pleurodiadema nudum Cotteau is illustrated for the first time from Poland. Taphonomic observations of echinoderms from the Kimmeridgian limestones of the ?ód? Depression suggest that they did not undergo a long post-mortem transport. The high degree of disarticulation, however, supports their prolonged post-mortem seafloor exposure.  相似文献   

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