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1.
Four new brachiopod species from the order Acrotretida (class Lingulata): Picnotreta saryarkensis sp. nov., Stilpnotreta propria sp. nov., Anabolotreta firma sp. nov., and Batenevotreta variabilis sp. nov. are described from the Agyrek Mountains, northeastern Central Kazakhstan from two olistoliths of limestones, which contain the uppermost Middle and lowermost Upper Cambrian fauna and are located in the Upper Ordovician olistostrome. These new species supplement the described earlier brachiopod assemblage from this region (Koneva and Ushatinskaya, 2008). Strong age and intraspecific variability of some Kazakh acrotretids is shown.  相似文献   

2.
Abstract: Two new bryozoan species are described from the Upper Ordovician Sassito Formation of the Argentinean Precordillera: Moyerella  spinata sp. nov. and Phylloporina  sassitoensis sp. nov. The bryozoans are found in cool‐water carbonates. The Silurian genus Moyerella is reported the first time in the Ordovician, showing palaeobiogeographic connections with Estonia and Siberia.  相似文献   

3.
Abstract: A diverse brachiopod fauna from a relatively deep water carbonate facies of the Upper Ordovician Beiguoshan Formation (uppermost Caradoc – lower Ashgill, middle Katian) is characterized by small shells and contains the oldest known Dicoelosia and Epitomyonia, two diagnostic taxa of deep water brachiopod palaeocommunities during the Late Ordovician and Silurian. Three new species are recognized: Dicoelosia cordiformis sp. nov., Dicoelosia perbrevis sp. nov. and Epitomyonia fui sp. nov. These pioneer forms of the family Dicoelosiidae show a relatively high degree of morphological plasticity. The shells of Dicoelosia from the Beiguoshan Formation range from the typical slender‐lobed form with a concavoconvex profile to the strongly equibiconvex, fat‐lobed morphotype that was not known previously until the late Silurian. The Beiguoshan dicoelosiids point to an important attribute of the deep water brachiopods: small generalists with high morphological plasticity, which make them ideal candidates as progenitors for the evolution of shallow water brachiopod faunas in shelf and platform depositional environments.  相似文献   

4.
Stromatoporoidea are widespread in the Upper Ordovician and Silurian beds of the Kozhim River (western slope of the Subpolar Urals). Five new species Cystostroma prodigiosum sp. nov., Stylostroma flabellatum sp. nov., Labechiina arguta sp. nov., Ecclimadictyon faveolatum sp. nov., and Araneosustroma astroplexum sp. nov. are described.  相似文献   

5.
New brachiopod taxa, Starnikoviella gen. nov., with the type species S. settedabanica sp. nov. (family Clitambonitidae), and Avdeevella gen. nov., with the type species A. mica sp. nov. (subfamily Glyptomeninae), from the Middle–Upper Ordovician boundary deposits of northeastern Russia are described.  相似文献   

6.
Two new genera and five new species of Archegocimicidae are described from the Upper Jurassic of the Shar-Teg locality in Mongolia: Shartegocimex rasnitsyni, gen. et sp. nov., S. distans, sp. nov., Shartegocorpus paranotalis, gen. et sp. nov., Saldonia formosa, sp. nov., S. insolita, sp. nov.  相似文献   

7.
A new genus and seven new species of the caddisfly families Philopotamidae, Polycentropodidae, Ecnomidae, Hydroptilidae, and Leptoceridae (Wormaldia nasticentia sp. nov., Holocentropus flexiflagrum sp. nov., Electrocyrnus perpusillus gen. et sp. nov., Archaeotinodes reveraverus sp. nov., Agraylea electroscientia sp. nov., Triplectides palaeoslavicus sp. nov., and Leptocerus solifemella sp. nov.) from the Rovno amber (Upper Eocene, Ukraine) are described  相似文献   

8.
The acritarchs and prasinophyte algae from the Upper Bringewood, Lower Leintwardine, Upper Leintwardine and Lower Whitcliffe formations of the Ludlow type area and surrounding regions are described. The following new taxa are proposed: Cymatiosphaera pumila sp. nov., Melikeriopalla pustula sp. nov., Cheleutochroa beechenbankensis sp. nov., Cymbosphaeridium molyneuxii sp. nov., Flammulasphaera bella gen. et sp. nov., Percultisphaera incompta sp. nov., Salopidium aldridgei sp. nov. and Umbellasphaeridium? wicanderi sp. nov. A holotype is defined for Lophosphaeridium galeatum Hill and a further 34 new taxa are described under open nomenclature. Two biozones, identified by the first appearance of the zone taxon, are defined in the Sunnyhill section, Ludlow [Global Stratotype Section and Point (GSSP) for the base of the Ludfordian Stage, Ludlow Series]. The base of the Leoniella vilis Biozone is identified at 4.52m below the top of the Upper Bringewood Formation at Beechenbank, Aymestrey. The base of the Triangulina sanpetrensis Biozone is identified at 15.49m above the base of the Lower Leintwardine Formation and Ludfordian Stage at the Sunnyhill section. These biozones allow correlation with sections in north–west Spain, Podolia and Gotland. The possibility of using Visbysphaera whitcliffense and U.? wicanderi as biozonal indicators is suggested.  相似文献   

9.
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   

10.
Permian Eoblattida, which include the families Tillyardembiidae, Protembiidae (=Sylvardembiidae), Soyanopteridae, and Idelinellidae, are reviewed. The latter family is revised; it includes Idelinella macroptera Storozhenko, 1997 from the Middle Permian (Lower Kazanian Substage) of northern European Russia, Permostriga augustalis Novokshonov, 1999, Sylvastriga miranda Aristov, 2004, Strigulla cuculiophora (Aristov, 2002) comb. nov., Cucullistriga cucullata Aristov et Rasnitsyn, gen. et sp. nov., Scutistriga scutata Aristov et Rasnitsyn, gen. et sp. nov. from the Lower Permian (Kungurian Stage) of the Urals, Permeoblatta borealis Rasnitsyn et Aristov, 2010 from the Upper Permian (Upper Severodvinian Substage) of northern European Russia, and probably also Rasstriga americana Aristov et Rasnitsyn, gen. et sp. nov. from the Upper Carboniferous (Desmoinesian Stage) of Illinois.  相似文献   

11.
New stonefly species of the family Palaeonemouridae, Palaeonemoura issadensis, sp. nov., Palaeotaeniopteryx laeta, sp. nov., and P. triternata, sp. nov., are described from the Tatarian (Upper Permian) locality of Isady (Severodvinian Stage of the Vologda Region).  相似文献   

12.
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   

13.
Abstract: Palaeoscolecidan worms are rare, Early Palaeozoic fossils with uncertain affinities within the Ecdysozoa. They are locally abundant in the Cambrian and scattered in the Early Ordovician, but very sparse thereafter. Forty‐four specimens have been collected from the Middle Ordovician of the Builth‐Llandrindod Inlier of Mid Wales and include well‐preserved material assigned to seven new genera, with four additional species in open nomenclature. An additional specimen from the Arenig Pontyfenni Formation of South Wales is also described in open nomenclature. The total demonstrates much greater palaeoscolecid diversity than hitherto suspected for this time. The specimens are preserved as cuticle fragments in shales and siltstones, often of submillimetre size but in many cases with excellent preservation. The level of detail preserved in some is equal to that found in Cambrian phosphatized faunas. The new approach to collecting, and the recognition that this material can yield taxonomically useful information, opens new avenues for palaeoscolecidan research in siliciclastic environments. The new taxa are the following: Radnorscolex bwlchi gen. et sp. nov., Aggerscolex murchisoni gen. et sp. nov., Bullascolex inserere gen. et sp. nov., Wernia eximia gen. et sp. nov., Ulexiscolex ormrodi gen. et sp. nov., Pluoscolex linearis gen. et sp. nov. and Loriciscolex cuspidus gen. et sp. nov. The high diversity, and the taxonomic separation from known groups described primarily from Cambrian carbonates, implies that palaeoscolecidans either diversified significantly during the Ordovician or were taxonomically segregated between carbonate and siliciclastic settings. Palaeobiological findings also include confirmation that some palaeoscolecid basal cuticles were solid and others reticulate, plates (and platelets) could form by lateral accretion, plates were in part primarily phosphatic and in part organic and that in at least some groups, platelet secretion occurred external to plate secretion.  相似文献   

14.
This study documents previously unknown taxonomic and morphological diversity among early Palaeozoic crinoids. Based on highly complete, well preserved crown material, we describe two new genera from the Ordovician and Silurian of the Baltic region (Estonia) that provide insight into two major features of the geological history of crinoids: the early evolution of the flexible clade during the Great Ordovician Biodiversification Event (GOBE), and their diversification history surrounding the end‐Ordovician mass extinction. The unexpected occurrence of a highly derived sagenocrinid, Tintinnabulicrinus estoniensis gen. et. sp. nov., from Upper Ordovician (lower Katian) rocks of the Baltic palaeocontinent provides high‐resolution temporal, taxonomic and palaeobiogeographical constraints on the origin and early evolution of the Flexibilia. The Silurian (lower Rhuddanian, Llandovery) Paerticrinus arvosus gen. et sp. nov. is the oldest known Silurian crinoid from Baltica and thus provides the earliest Baltic record of crinoids following the aftermath of the end‐Ordovician mass extinction. A Bayesian ‘fossil tip‐dating’ analysis implementing the fossilized birth–death process and a relaxed morphological clock model suggests that flexibles evolved c. 3 million years prior to their oldest fossil record, potentially involving an ancestor–descendant relationship (via ‘budding’ cladogenesis or anagenesis) with the paraphyletic cladid Cupulocrinus. The sagenocrinid subclade rapidly diverged from ‘taxocrinid’ grade crinoids during the final stages of the GOBE, culminating in maximal diversity among Ordovician crinoid faunas on a global scale. Remarkably, diversification patterns indicate little taxonomic turnover among flexibles across the Late Ordovician mass extinction. However, the elimination of closely related clades may have helped pave the way for their subsequent Silurian diversification and increased ecological role in post‐Ordovician Palaeozoic marine communities. This study highlights the significance of studies reporting faunas from undersampled palaeogeographical regions for clade‐based phylogenetic studies and improving estimates of global biodiversity through geological time.  相似文献   

15.
Ostracodes Healdianella splendida Belousova, Paraparchites ganelini sp. nov., Paraparchites? hivachensis sp. nov. and Arcibairdia vodopadniensis sp. nov. are described from the Upper Permian deposits of the Khivach Formation (Kolyma-Omolon Basin, Eastern Siberia). Paraparchites species most closely resemble ancient Paleozoic ostracodes of the Boreal province. Valve morphology of Healdianella and Acribairdia points to their similarity to ostracodes from the upper levels of the Upper Permian of the Tethyan realm.  相似文献   

16.
Abstract: A rich coral‐associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region. This discovery more than doubles the number of known fossil decapod species from Malta. The fossil bivalve Jouannetia (J.) semicaudata Des Moulins, 1830 and the extant decapod Maja goltziana D’Oliveira, 1888, are also recorded for the first time from Malta. Other Neogene coral‐associated decapod assemblages are investigated and correlated with the new assemblage from Malta. The migration of taxa between the Mediterranean region and the Paratethys, particularly during the Lower Badenian (Langhian), is evidenced by the strong affinity of the Maltese decapod assemblage with that of the Middle Miocene Badenian assemblages from Hungary, Poland and Ukraine. Upper Miocene, Messinian assemblages from Spain, Algeria and Morocco are also similar to that from Malta.  相似文献   

17.
Based on the studying of gastropods collected by P.A. Gerasimov from the Cretaceous beds of the Volga region, four new species are established: Avellana hauteriviensis sp. nov. from the Upper Hauterivian of the Ulyanovsk region, “Palaeorissoina” sokolovensis sp. nov., O. sinzowi sp. nov., and Nerineopsis turritum sp. nov. from Lower Aptian of the Saratov region. The Upper Hauterivian for the first time yielded representatives of the genera Pseudomelania s. l., Ampullina, and Sulcoactaeon. The specimens of Cirsocerithium subspinosum Deshayes, 1842, Ringinella obtusa (Nackij, 1916), and Crispotrochus humilis (Trautschold, 1865) found in the Lower Aptian of the Volga region are figured for the first time.  相似文献   

18.
Cambrian spicular sponge faunas are dominated by a distinctive assemblage of demosponges and hexactinellids that are known from Burgess shale-type faunas worldwide. Most of these are previously unknown outside the Lower-Middle Cambrian (and perhaps Tremadoc) and have no obvious close relatives in later sequences. This paper describes examples of Choia sp., Pirania auraeum sp. nov. and Hamptonia christi sp. nov. from the Arenig of Morocco, associated with isolated hexactinellid spicules. A summary of the stratigraphic ranges of the major Cambrian sponge lineages is provided. These indicate an environmental contrast in the Lower Palaeozoic evolution of hexactinellids and non-lithistid demosponges, with demosponges probably undergoing cryptic diversification in nearshore environments during the Upper Ordovician.  相似文献   

19.
Two new species of Nummulites and one subspecies of Orbitoclypeus from the Eocene of the Crimean Mountains and Mangyshlak Peninsula are described in detail. Nummulites alexisi sp. nov. and Orbitoclypeus munieri major subsp. nov. come from the Upper Ypresian, while Nummulites ninikae sp. nov. is from the Lower-Middle Lutetian. The phylogenetic position of new taxa is discussed.  相似文献   

20.
Two new lacewing species, Prohemerobius minor sp. nov. (Prohemerobiidae) and Sogjuta shartegica sp. nov. (Osmylidae), are described from Upper Jurassic deposits of the Mongolian locality Shar-Teg.  相似文献   

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