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1.
The brachiopod fauna from the base of the Bryn Siltstone Formation (middle Caradoc), Glyn Ceiriog, north Berwyn Hills, North Wales, consists of Platystrophia elevata sp. nov., Salopia abbreviata sp. nov., Kiaeromena ungula (M'Coy) and unnamed species of Hesperorthis?, Reuschella and Bicuspina. The dominant brachiopod species, Leptaena (Leptagonia) ungula M'Coy, 1851 is revised and its current assignment to the leptaenid genus Kiaeromena confirmed, based on the examination of type and topotype material from the Bryn Siltstone Formation. Kiaeromena spjeldnaesi nom. nov. is proposed to replace the junior homonym K. ungula Spjeldnæs, 1957 for that congeneric species from the upper Caradoc rocks of Ringerike, southern Norway. The fauna as a whole is unusual within the context of the Anglo-Welsh province and may represent a rare preserved nearshore community.  相似文献   

2.
To most modern-day students of palaeontology, the name Frederick M'Coys (c. 1823–1899) is familiar; to other Earth scientists it possibly won't be. Who was M'Coy and why is 1994 a significant year for palaeontologists and historians of the Earth sciences? This year marks the sesquicentenary of the publication of M'Coy's A Synopsis of the Characters of the Carboniferous Limestone Fossils of Ireland (1844). This monograph, together with that for Lower Palaeozoic fossils, A Synopsis of the Silurian Fossils of Ireland, published two years later, which describe the collections of Richard Griffith, remain highly important to palaeontologists working today.  相似文献   

3.
4.
The Carboniferous fenestrate bryozoan Synocladia carbonaria Etheridge Jun. (1873a) is redescribed. Originally assigned to Synocladia and subsequently diagnosed as a variety of Synocladia biserialis Swallow by Etheridge Jun. (1873b), S. carbonaria is here considered to be a distinct species. Synocladia(?) scotica Young and Young (1878) is conspecific with S. carbonaria, as suggested by Graham (1975). Graham (1975) established the new genus Lanarkopora, naming S. carbonaria and S.(?) scotica in synonomy, with S. carbonaria, the senior synonym, being selected as the type species. Re-examination of the type material of S. carbonaria and S.(?) scotica has shown that they are referable to the genus Septopora Meek, and Lanarkopora is herein designated a junior synonym of Septopora.  相似文献   

5.
Nautilus subplicatusSteinmann, 1895 is a latest Cretaceous species of nautiloid which is common in southern South America (Chile, Argentina) and the Antarctic Peninsula and which is best assigned to the genus EutrephocerasHyatt, 1894. Nautilus dorbignyanusForbes in Darwin, 1846 and Nautilus valenciennii Hupé in Gay, 1854 are here considered to be senior synonyms which later authors have apparently overlooked. The type material of these two taxa is reillustrated. On the basis of this and additional material it is demonstrated that only a single nautiloid species occurs in the Quiriquina Formation of late Maastrichtian age. For this we propose to use N. dorbignyanus as the oldest available name.  相似文献   

6.
The coal-bearing, alternating marine and non-marine Longzhaogou Group in eastern Heilongjiang, northeastern China, has long been considered as Jurassic, or mainly Jurassic, in age. However, recent studies have demonstrated that the ammonites and dinoflagellate cysts are of Early Cretaceous age. This has now been confirmed by new radiolarian evidence. The radiolarian fauna recovered from the upper Qihulin Formation of the Longzhaogou Group consists of nine poorly preserved species referable to nine genera. Novixitus is a Cretaceous genus, and the specimens of Archaeodictyomitra sp. and Xitus sp. recovered resemble A. vulgaris Pessagno and X. spicularius (Aliev), respectively.  相似文献   

7.
Six species of Bryozoa, three new, of Upper Visean age are described from Tullaghoge, County Tyrone, Ireland. The assemblage suggests shallow water conditions subject to wave action. The new species are Dyscritella tyronei, Stenophragmidium incrustans, and Sulcoretepora? ramosa.  相似文献   

8.
There is (or should be) an archived specimen, a reference copy if you like, for all living and fossil species that have been described scientifically. These physical specimens, so‐called name‐bearing type specimens, are housed at museums or academic institutes around the world for researchers to study and perhaps compare with their own material. But what about our own species, Homo sapiens?  相似文献   

9.
We describe a large collection of fossil ‘waterfowl’ bones that are referable to the extinct clade Presbyornithidae (Anseriformes). All of these fossils were collected between 1971 and 1994 from Upper Paleocene and Lower Eocene sediments at the Tsagaan Khushuu site in the Gobi Desert of southern Mongolia. The collection includes specimens referred to a new small species within the genus Presbyornis Wetmore, 1926 as well as large numbers of bones that we place in the genus Presbyornis. On this basis of the Tsagaan Khushuu collection we suggest that several species of Presbyornis likely coexisted in this region; indeed, the presence of large numbers of middle‐sized, morphologically consistent but probably ecologically disparate species at the Tsagaan Khushuu site is consistent with the range of variation seen, for example, in taxa of extant dabbling ducks (Anatini). Although the anatomy and phylogenetic position of Presbyornithidae (in particular Presbyornis) are well known, this material from Mongolia further demonstrates the prevalence of these birds in aquatic and semi‐aquatic habitats by the earliest Paleogene. Because presbyornithids are also well documented from the late Cretaceous, their palaeoecology and morphological diversity provides a clue to selective avian survivorship across the Cretaceous‐Paleogene (K‐Pg) boundary. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
This paper describes a new ichthyosaur specimen from the Stonebarrow Marls Member (Charmouth Mudstone Formation) of Charmouth, Dorset. It is substantially complete and various characters of the skull (snout ratios and basioccipital morphology) and appendicular skeleton (the number of digits on the hind paddle, which can be used to infer the number of digits on the front paddle) indicate that the specimen is referable to Ichthyosaurus communis. This provides the first direct evidence for the presence of I. communis in the Pliensbachian, extending the stratigraphic range of the species. The specimen also preserves a probable gullet content, which demonstrates that fish formed part of the diet of this individual.  相似文献   

11.
A new species of the sail-crested pterosaur Tupuxuara is described from the Santana Formation of Brazil, Tupuxuara deliradamus sp. nov. The holotype, a partial skull, and a larger, partial skull referred to the same taxon differs from Tupuxuara leonardii by having a nasoantorbital fenestra with an acutely-angled posterior border with a long, straight posterodorsal margin, a reclined cranium, and an orbit situated entirely in the ventral half of the nasoantorbitral fenestra. Unfortunately, neither specimen is comparable with the fragmentary rostrum representing Tupuxuara longicristatus. In addition, resolution of a recent nomenclatural problem over the correct name for the clade containing Tupuxuara and its sister taxon, Thalassodromeus, is provided. Both genera are used by different authors as the nomenclatural basis for the group, but “Tupuxuaridae” has never been explicitly erected as a new taxon, and therefore fails to meet ICZN criteria that new taxa are only valid if authors clearly indicate their intention to establish new names. By contrast, “Thalassodrominae” was explicitly erected as a name for the Thalassodromeus + Tupuxuara clade, thereby fulfilling all ICZN requirements for naming of a new taxon and making Thalassodromeus stand as the type genus for this group.  相似文献   

12.
The morphology of the horn-core structure and section shape of the Bos galerianus type specimen, as well as the general anatomy of the frontal and occipital areas of the skull, suggest that the skull is better attributed to the Indian genus Hemibos. This finding contributes to our understanding of faunal dispersal patterns into Europe at the Early–Middle Pleistocene transition.  相似文献   

13.
Yabeinosaurus was the first lizard genus described from the Early Cretaceous Jehol Biota of China. The holotype of the type species, Y. tenuis, is an immature skeleton but it has been lost for decades. A second species, Y. youngi, was erected based on another immature skeleton and is distinguished by its longer, more gracile limbs. In 2001, a juvenile skeleton from the Jingangshan locality of Liaoning was designated as the neotype for Y. tenuis. Subsequently, several further specimens from other localities, juvenile and adult, have been attributed to this species. Here we describe a second lizard specimen from the neotype locality. In anterior tooth shape, finger-like mandibular angular process, cranial sculpture, maxilla shape, and short, robust humerus, the new specimen resembles adult and subadult material currently attributed to Y. tenuis, but it differs in having bicuspid posterior teeth and a straight rather than a hooked angular process of the mandible. We propose a new species (Y. bicuspidens sp. nov.) for this specimen which represents the first occurrence of bicuspid teeth in an Early Cretaceous lizard from China. However, the recognition of a second species at the neotype locality raises a taxonomic problem. Due to the immaturity of the designated holotype and neotype of Y. tenuis, they cannot be coded for the jaw and dental characters that distinguish the two robust-limbed species. This renders Yabeinosaurus tenuis a nomen dubium. Here we propose that Yabeinosaurus tenuis should be treated as a historic taxon, permitting retention of the generic name under ICZN rules, and erect a second new species (Y. robustus sp. nov.) for the principal robust-limbed morphotype in the Jehol Biota with monocuspid posterior teeth and a hooked angular process.  相似文献   

14.
A total of 165 samples were collected from the Qom Formation investigated in a stratigraphic section north of Deh Namak, in Central Iran. From these, 35 genera and 47 species of benthic foraminifera were identified. The age of the studied section is Early Miocene (Aquitanian to Early Burdigalian) based on the occurrence of Borelis melo curdica, Meandropsina anahensis, Meandropsina iranica, Elphidium sp. 14, Peneroplis farsensis, and Triloculina tricarinata. The thickness of the Qom Formation is 401 m of which 161.2 m is early Burdigalian in age. Foraminiferal assemblages in the Deh Namak section are referable to the Borelis melo group-Meandropsina iranica Assemblage Zone and Miogypsinoides-Archaias-Valvulinid Assemblage Zone of [Adams, T.D., Bourgeois, F., 1967. Asmari biostratigraphy. Iranian Oil Operating Companies, Geological and Exploration Division, Report1074 (unpublished) 1–37.] described originally from the Asmari Formation.  相似文献   

15.
Three new species of the extinct genus of Eoptychopterina from the Eoptychopteridae  相似文献   

16.
The fossil skeletal record of birds from the Cenozoic of Switzerland is rather poor, despite the fact that avian tracks have been described from twenty tracksites. We review the Swiss fossil skeletal avifauna with emphasis put on new material discovered in the collection of the Natural History Museum Basel. This material includes two new owls (Strigiformes), one from a Late Eocene fissure filling from the Gösgen canal, and another from the Late Oligocene of Mümliswil. The Eocene owl specimen consists of a partial, distal tarsometatarsus, and is therefore too incompletely preserved to allow for reliable hypotheses concerning its taxonomic affinities. It does, however, display features resembling members of the extinct family Palaeoglaucidae. The Oligocene specimen is tentatively attributed to the genus Oligostrix, and it is the youngest representative of the extinct family Protostrigidae. Based on the first complete tarsometatarsus for this family, we erect a new species, ?Oligostrix bergeri. These two specimens represent the first record of fossil owls from Switzerland.  相似文献   

17.
《Cretaceous Research》2012,33(6):833-840
Nautilus subplicatus Steinmann, 1895 is a latest Cretaceous species of nautiloid which is common in southern South America (Chile, Argentina) and the Antarctic Peninsula and which is best assigned to the genus Eutrephoceras Hyatt, 1894. Nautilus dorbignyanus Forbes in Darwin, 1846 and Nautilus valenciennii Hupé in Gay, 1854 are here considered to be senior synonyms which later authors have apparently overlooked. The type material of these two taxa is reillustrated. On the basis of this and additional material it is demonstrated that only a single nautiloid species occurs in the Quiriquina Formation of late Maastrichtian age. For this we propose to use N. dorbignyanus as the oldest available name.  相似文献   

18.
New articulated specimens of the British Ordovician cystoid first mentioned under the name ‘Hemicosmites rugatus Forbes’ in 1848 allow its morphology and systematic affinities to be established for the first time. Despite being based on isolated plates, ‘H. rugatus Forbes’ has been reported from England and Wales, Belgium, France, Spain and Thailand, and has been attributed to four genera. It is characterized by a heteromorphic, circular stem, a theca with four basal, six infra‐lateral and eight lateral plates, all with sharp‐crested ridges running to plate angles, multiple arms in each ambulacrum and an extensive tegmen. These characters indicate it belongs in the family Caryocrinitidae and genus Caryocrinites. Caryocrinites rugatus had arms with lateral brachioles that folded in against the main arm axis, as in the type species C. ornatus Say. It is the first Ordovician species known to possess this character. Isolated plates show sorting and a few may represent other species of Caryocrinites s.l. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
Recent excavations in the Middle Triassic Prosanto Formation (Ladinian, Ct. Grisons, Switzerland) have produced new material of the genus Besania Brough 1939. These specimens show many previously unrecorded details. Some features differ from those of the type species Besania micrognathus, and we therefore erect a new species, Besania schaufelbergeri sp. nov. This new material has prompted a re-evaluation of the phylogenetic interrelationships of the genus. The taxon seems to be closely related to basal Halecostomi. An erratum to this article is available at .  相似文献   

20.
A new genus of terrestrial gastropod Badchisestis and three included species are described and assigned to the Cyclophoridae. Badchisestis cupaeformis, B. piriformis and the type species B. digitulus all come from the Middle Eocene, Alayan series of Badkhyz, southeast Turkmenia, in the region of Mt. Chakmaly-Chonga. Korobkov's diagnosis of the genus is as follows: Shells of medium (30 mm) to considerable (60 mm) size, elongate-ovate, dolioform, pyriform or oval-digitiform, consisting of six to nine slightly convex, low whorls, separated by a distinct surface suture. Height of last whorl 1;3, 2/5 or 1;2 the height of the whole shell. Aperture comparatively small, broader than high, in the form of a slightly truncated broad oval, angular in the parietal part, with a sulcus in the sutural angle. Peristomatal margins thickened and turned back towards the dorsal surface. Pseudo-umbilicus, narrow not fringed. Outer surface with oblique, converging slender riblets. — N. F. Sohl.  相似文献   

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