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1.
The upper and uppermost Famennian succession (Upper Devonian) of the Band-e Bayan Domain (also known as the Axial Zone), a Cimmerian terrane of western Afghanistan (northern margin of Gondwana), yielded diverse brachiopod faunas that are dominated by the spiriferides. Among the latter, six species belonging to four genera, previously erected by D. Brice in the seventies and also known from Iran, are reappraised on the basis of their type material and re-illustrated. The genera Enchondrospirifer and Eobrachythyris are transferred to the subfamilies Cyrtospiriferinae (Cyrtospiriferoidea) and Prospirinae (Spiriferoidea), respectively, whereas the ornament and micro-ornament of both Afghan species of Dichospirifer are documented. The genus Ghorispirifer nov. gen. (Cyrtiopsinae) is erected with Cyrtiopsis graciosa chakhaensis Brice as type species, and includes a second species, namely Cyrtiopsis lapparenti Brice. The new genus is characterized notably by the strong development of ventral apical callosities. Upper Devonian (Frasnian?) brachiopods from the Band-e Bayan Domain described by Maillieux in the first half of the 20th century are revised and photographically illustrated for the first time. The brachiopod generic diversity recognized in Afghanistan (Band-e Bayan Domain, Central Mountains) prior to the Hangenberg Crisis is very high in some sections of the Band-e Bayan Domain (Rhuk pass section, and to a lesser extent at Robat-e-Pai), as also observed in contemporaneous successions of South China and contrary to what is reported in Western Europe (Franco-Belgian Basin for instance).  相似文献   

2.
Two new strophomenid species, Leptagonia barunkhuraica sp. nov. (Famennian) and Floweria mongolica sp. nov. (Frasnian), from the Upper Devonian of the Barunkhurai Depression of southern Mongolia are described.  相似文献   

3.
A bryozoan fauna containing seven species is described from the Upper Frasnian (Upper Devonian) rocks in the Khoshyeilagh Section, Alborz Mountains (northern Iran). The studied bryozoan assemblage includes one new trepostome species, Eridotrypella alborzensis sp. nov., an additional four species identified at species level: two trepostomes, Minussina akkayaensis Volkova, 1974 and Leptotrypella inaudita Morozova, 1961, and two rhabdomesine cryptostomes, Bigeyella mariae (Morozova, 1961) and Saffordotaxis multispinata (Morozova, 1955). Furthermore, two species are described in open nomenclature: the trepostome Schulgina sp. and the rhabdomesine cryptostome Nicklesopora sp. The studied fauna shows a close similarity at the species level between northern Iran and the Altai-Sayan Folded Belt (Russia), south China, and Transcaucasia.  相似文献   

4.
New bryozoans Saffordotaxis altaicus sp. nov. from the Givetian Stage (Middle Devonian) and Cyphotrypa olgae sp. nov. and Crustopora aliena sp. nov. from the Famennian Stage (Upper Devonian) are described from the Devonian of Gorny Altai.  相似文献   

5.
Svalbardia banksii sp. nov., is described from the Upper Devonian (Frasnian) Fish Cabin Creek locality near Pond Eddy, New York. The compression consists of ultimate branches bearing spirally arranged, unwebbed leaves. The unwebbed leaves are up to 3.2 cm long, are somewhat flexuous, and dichotomize in more than one plane. The new species is similar to the reconstruction of Actinoxylon banksii from the Middle Devonian (Givetian) of New York and strengthens the supposed relationship between Svalbardia polymorpha and Actinopodium nathorstii from Mimerdalen, Spitzbergen.  相似文献   

6.
The placoderm Plourdosteus livonicus (Eastman) (Euarthrodira, Coccosteina) from the Upper Timanian Mikhailovskii Fish Assemblage of the Central Devonian Field is described. The composition and structure of the assemblage are discussed and compared with later Frasnian fish assemblages of the Central Devonian Field.  相似文献   

7.
New conodont species of the genus Polygnathus (P. krutoensis sp. nov., P. makhlinae sp. nov., P. menneri sp. nov., P. obruchevae sp. nov.) are described from the Evlanovian-Livnian (Upper Devonian) deposits of the Voronezh Anteclise (central regions of the Rassian platform). The ontogenetic series of the new species are presented.  相似文献   

8.
9.
A new genus and species of pachyosteomorph arthrodire, Omalosteus krutoensis gen. et sp. nov. from shallow-water marine deposits of the Evlanovo Regional Stage (Upper Frasnian, Upper Devonian) of the Central Devonian Field is described. It is tentatively referred to the family Trematosteidae Gross, 1932, which was earlier believed to be endemic to central Europe. The new genus is characterized by a rounded, dorsoventrally compressed cross section of the pectoral region and smooth head shield and postcranial membrane bones. The centrale is elongated, forming a narrow lateral lobe. The praeorbitale, postorbitale, and centrale come in contact in the center of the orbital region. The mediodorsale is wide, its carinal process projects considerably posteriorly. The anterior margin of the anterior ventrolaterale lacks articular facets for the interlaterale.  相似文献   

10.
JAN BOHATÝ 《Palaeontology》2011,54(5):1177-1197
Abstract: The discovery of new specimens and the restudy of known collections result in revision of the diagnosis and the stratigraphic distribution of the disparid crinoid genus Stylocrinus, from the Middle and Upper Devonian of Europe, Asia and Australia. The consistent development of three basal plates, the atomous arms with internally inclined edges adjoining laterally with adjacent brachials in an interlocking network and an apparently rudimentary pinnulation is recognised. The high ecophenotypic plasticity of the common species S. tabulatus negates the validity of several former subspecies and demonstrates the general morphologic variability of the aboral cup proportions. This contrasts with the low morphological spectrum of rarer stylocrinid species. With exclusion of ‘S. elimatus’ (Silurian) from Stylocrinus, the genus is limited to the Devonian. A neotype is proposed for the lost holotype of S. tabulatus. Stylocrinus prescheri sp. nov. is described from the Eifelian to Givetian of Europe and Asia. The first evidence of the gastropod grazing trace fossil Radulichnus on a crinoid aboral cup (S. tabulatus), the post‐mortem incurred ossicular‐boring of radial and basal plates as well as the post‐mortem encrusting by a rugose coral are further observations on Stylocrinus aboral cups.  相似文献   

11.
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13.
A new pycnosteid species, Schizosteus shkurlatensis sp. nov. (Agnatha, Psammosteiformes), from the Staryi Oskol beds (Givetian, Middle Devonian) of the Voronezh Region is described. This is the first species of the genus Schizosteus Obruchev from the Central Devonian Field. The similarity between species of this genus and early species of Psammolepis is discussed.  相似文献   

14.
15.
en|This paper deals with a new species ofOtarion [Otarion (Otarionella) greifensteinen.se n. sp.] from the ‘Greifenstein Limestone’ of the ‘Wiege’ near Greifenstein, close to the village Greifenstein near Herborn (Lahn-Dill area, Hesse, Germany), which is described, figured and compared with all known species of this subgenus. It is a typical trilobite of the hercynian-bohemian shallow marine facies near the Lower-/Middle Devonian boundary (Upper Emsian / Lower Eifelian), which extends up into the lower part of the Middle Devonian (Lower Eifelian). The trilobites are transported for short distances only and, thus, are parautochthonous elements of the Greifenstein Facies.  相似文献   

16.
New genus and species of punctate rhynchonellids Sharovaella mirabilis are described from the Famennian (Upper Devonian) of Transcaucasia.  相似文献   

17.
Abstract: Microconchid tubeworms (Tentaculita) encrusting brachiopod shells have been investigated from the upper Frasnian – lower Famennian (Upper Devonian) deposits of the Central Devonian Field, Russia. The condition of microconchids and associated encrusting taxa is reported for the first time from the early Famennian recovery interval (crepida Chron) following the Frasnian–Famennian mass extinction. Two species, one new (Palaeoconchus variabilis sp. nov.) and the second one in open nomenclature (Palaeoconchus sp.), are described. Compared to lower Famennian specimens, they seem to be preferentially grouped on the anterior parts of the brachiopod host shells, which are interpreted as the most suitable sites away from the sea‐bottom and sediment. During the late Frasnian (Late rhenana Chron), microconchids, outnumbered by cornulitids and as abundant as foraminifers, were also associated with trepostome bryozoans, tabulates, rugose corals and various problematic encrusters. During the early Famennian recovery interval encompassing the crepida Chron, microconchids greatly outnumbered all associated encrusters, including the previously dominant cornulitids, while foraminifers, tabulates and rugose corals vanished. Early Famennian microconchids, represented by the single, albeit very abundant, species Palaeoconchus variabilis sp. nov., were opportunists that rapidly colonised the environment during the ongoing transgression following the regression‐driven biotic crisis in the area of the Central Devonian Field. In comparison to their late Frasnian predecessors and even other Middle Devonian specimens, no size reduction (the so‐called Lilliput effect) of early Famennian microconchid tubes was observed. It is probable that microconchids either rapidly attained their ‘normal’ sizes or they did not suffer any dwarfism following the Frasnian–Famennian event.  相似文献   

18.
Based on the study of the neotype and the astogeny of the type specimens of the species Ascopora nodosa (Fischer von Waldheim, 1837), the diagnosis and species composition of the genus Ascopora Trautschold, 1876 are emended. The genus Ascopora and three species out of the five included in this genus—A. nodosa (Fischer von Waldheim, 1837); A. sokolovae Schulga-Nesterenko, 1955; and A. latiaxis Schulga-Nesterenko, 1955—are described. A new genus, Tetrasella gen. nov., with the type species T. blanda sp. nov. is described. This genus comprises five species, transferred from the composition of the genus Ascopora. An emended diagnosis of the genus Ascoporella Krutchinina, 1986, is provided. This genus comprises nine species, of which two, A. lecta sp. nov. and A. mera sp. nov., are described as new species.  相似文献   

19.
The bothriolepiform antiarchs Tenizolepis asiatica (Obrucheva, 1955), Bothriolepis kassini Malinovskaja, 1988, and B. babichevi Malinovskaya, 1992 from the Givetian (Middle Devonian) of Central Kazakhstan are redescribed. Tenizolepis bychkovi Malinovskaya, 1992, known from the Konyr Formation of the Trudovoe vertebrate locality, is considered to be a synonym of B. babichevi. The history of investigation of bothriolepiforms from Kazakhstan is discussed. The system and phylogeny of antiarchs are discussed.  相似文献   

20.
Philippe Janvier 《Geobios》1979,12(4):605-608
The Upper Devonian of the Kerman region (Central Iran) has yielded but a few remains of antiarchs. Some ofthem may be referred to the almost world-wide distributed genus Asterolepis, whereas others are suggestive of the genera Byssacanthus and Stegolepis, previously recorded only from the Middle and Upper Devonian of Soviet Union.  相似文献   

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