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Tytuł:
Late Cretaceous sharks Cretoxyrhina and Cardabiodon from Montana, USA
Autorzy:
Siverson, M
Lindgren, J.
Powiązania:
https://bibliotekanauki.pl/articles/22717.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
shark
USA
Cretoxyrhina
Cretaceous
Late Cretaceous
Montana
biostratigraphy
Lamniformes
Cardabiodon
paleontology
Opis:
The middle part of the Cretaceous represents a time of high diversity and rapid rates of dental evolution in lamniform sharks. Several species had a very wide spatial distribution with recorded occurrences in both hemispheres. We have examined isolated teeth of Cretoxyrhina and Cardabiodon from eastern Russia, Mangyshlak in Kazakhstan, and the Western Interior of the USA. The material indicates that samples of isolated teeth of the two genera have high potential in intercontinental correlation of the upper Albian to mid−Turonian interval in mid−palaeolatitude deposits, poor in other age−diagnostic fossil groups. The utilization of these lamniforms in mid−Cretaceous biostratigraphy is currently hampered by the nearly total absence in the literature of well illustrated, well dated and sufficiently large samples of isolated teeth of the two genera. As a first step towards the establishment of an intercontinental elasmobranch zonation for mid−Cretaceous strata in temperate palaeo−regions, we describe and illustrate samples of teeth of Cardabiodon venator sp. nov. and Cretoxyrhina mantelli from the lower middle Turonian Collignoniceras woollgari regulare Zone in the Fairport Member of the Carlile Shale in east−central Montana, USA. These samples could serve as reference points for future biostratigraphic studies of Cretoxyrhina and Cardabiodon. The extinction of Cretoxyrhina may be diachronous, as regional last appearance data range from the upper Santonian (Marsupites testudinarius Zone) in Western Australia to the uppermost lower Campanian (informal Belemnellocamax mammillatus zone; a lateral equivalent to the German Gonioteuthis quadrata gracilis/Belemnitella mucronata Zone) in southern Sweden.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new ankylosaurid from the Late Cretaceous Two Medicine Formation of Montana, USA
Autorzy:
Penkalski, P.
Powiązania:
https://bibliotekanauki.pl/articles/945878.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
ankylosaur
Dinosauria
Ornithischia
Ankylosauridae
systematics
paleontology
Campanian
Late Cretaceous
Cretaceous
Two Medicine Formation
Montana
USA
Opis:
Oohkotokia horneri gen. et sp. nov. is described based on a specimen in the collections of the Museum of the Rockies, Montana, USA. Oohkotokia exhibits a unique combination of characters not seen in other late Campanian North American ankylosaurids: prominent, horn-like, trihedral squamosal bosses, a small, undistinguished median nasal plate on the dorsal surface of the rostrum, a relatively small occipital condyle, a smooth, finely pitted osteoderm external texture, and triangular lateral osteoderms. Other specimens from the Two Medicine Formation are referable to Oohkotokia. O. horneri, Euoplocephalus tutus, Dyoplosaurus acutosquameus, and Scolosaurus cutleri separate stratigraphically.
Źródło:
Acta Palaeontologica Polonica; 2014, 59, 3; 617-634
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Early Pennsylvanian xenacanth chondrichthyans from the Swisshelm Mountains, Arizona, USA
Autorzy:
Johnson, G.D.
Thayer, D.W.
Powiązania:
https://bibliotekanauki.pl/articles/21790.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
vertebrate
fauna
xenacanth chondrichthyan
chondrichthyan
Swisshelm Mountains
Arizona
USA
Chondrichthyes
Xenacanthiformes
Bransonelliformes
Orthacanthus
Triodus
Bransonella
Opis:
Three genera of xenacanths, based on isolated teeth, occur in the lepospondyl (amphibian)−dominated fauna from the upper Black Prince Limestone (late Bashkirian). Orthacanthus donnelljohnsi sp. nov. teeth, with carinae lacking serrations on the compressed principal cusps, and only one intermediate cusp, represent both adult and juvenile teeth. Heterodonty occurs in both adult and juvenile dentitions. The absence of serrations is unique among Pennsylvanian species of Orthacanthus. Teeth with often highly asymmetrical bases with an aborally−flexed lingual marginal flange (= anterolingual shelf) and a single intermediate cusp are assigned to Triodus elpia sp. nov. A central foramen occurs in the base, unlike most other species; the moderately compressed principal cusps bear generally straight cristae. They represent the first reported occurrence of Triodus in the Paleozoic of North America. Five teeth, with cristae extending from the cusps onto their bases, belong to Bransonella. Two are questionably assigned to Bransonella nebraskensis, one to B. ?lingulata with its labio−lingually elongated apical button and smaller than normal intermediate cusp, and one each to Bransonella sp. “A” and “B”. Bransonella sp. “A” has a base wider (labio−lingual) than long, the reverse of the other Bransonella teeth. Bransonella sp. “B” is distinctly different, as it lacks an intermediate cusp (as in some B. lingulata teeth), and the basal tubercle is beneath one of the cusps (with no evidence of deformity).
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chaetognath grasping spines from the Upper Mississippian of Arkansas [USA]
Autorzy:
Doguzhaeva, L A
Mutvel, H.
Mapes, R.H.
Powiązania:
https://bibliotekanauki.pl/articles/23070.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
grasping spine
fossil
USA
protoconodont
organic spine
phosphatized fossil
morphology
Arkansas
ultrastructure
Chaetognatha
paleontology
chaetognath
Opis:
Previously unidentified tiny (about 0.5 mm in length), hollow, gently curved, serrated spines probably originally composed of horny, organic fibers from the Upper Mississippian (Middle Chesterian = Namurian A equivalent or lower Serpukhovian) of Arkansas (USA) are described, and their probable chaetognath affinities are discussed. The specimens are preserved in an oval accumulation (about 15 mm long and 6 mm wide) of approximately 200 specimens within a small (about 25 mm in length) phosphatic concretion. For comparison, the grasping spines of the Recent chaetognath Eukrohnia hamata were examined. The Arkansas specimens are named Eoserratosagitta serrata gen. et sp. nov., and this genus is assigned to the Phylum Chaetognatha. The Upper Mississippian spines are also compared with protoconodonts. This comparison supports the hypothesis that the chaetognaths may have existed in the Cambrian.
Źródło:
Acta Palaeontologica Polonica; 2002, 47, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Globicephaline whales from the Mio-Pliocene Purisima Formation of central California, USA
Autorzy:
Boessenecker, R.W.
Perry, F.A.
Geisler, J.H.
Powiązania:
https://bibliotekanauki.pl/articles/945570.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Mammalia
Cetacea
Odontoceti
Delphinidae
Globicephalinae
paleontology
Pliocene
Purisima Formation
California
USA
Opis:
Oceanic dolphins (Odontoceti: Delphinidae) constitute the most speciose family of extant cetaceans, yet their fossil record is limited. Although several extinct species are known from Mediterranean and North Atlantic localities, there are few examples from deposits along the Pacific Rim. Despite the rich record of successive marine mammal fossil assemblages in the extensively sampled eastern North Pacific, only one fossil delphinid, Protoglobicephala (Pliocene, Baja California), has been described. We report globicephaline remains from the Mio-Pliocene Purisima Formation of Northern California, including a partial cranium and two isolated petrosals. The skull exhibits large ridges on the premaxillae, and cannot be referred to any extant globicephaline genus. Similarly, the petrosals cannot be referred to any described delphinid genus, although they are most similar to those of Globicephala. Linear regression analyses demonstrate that promontorium length and bony nares width scale significantly within delphinidans, and provide a new method for testing referrals of isolated fossil odontocete petrosals to taxa known only by crania. Applying this method to the new globicephalines from the Purisima Formation, we find the petrosals to be too small to represent the same taxon as the skull, thus indicating the presence of two separate species. Our results demonstrate that globicephalines had achieved a worldwide distribution by the early Pliocene, suggesting diversification of the subfamily by 5 Ma.
Źródło:
Acta Palaeontologica Polonica; 2015, 60, 1; 113-122
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Late Oligocene sharks and rays from the Chandler Bridge Formation, Dorchester County, South Carolina, USA
Autorzy:
Cicimurri, D.J.
Knight, J.L.
Powiązania:
https://bibliotekanauki.pl/articles/21710.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Late Oligocene
Oligocene
shark
ray
Chandler Bridge Formation
Dorchester County
South Carolina
USA
Chondrichthyes
Neoselachii
Opis:
A diverse vertebrate fauna, dominated by elasmobranch taxa, was collected from the upper Oligocene (Chattian) Chandler Bridge Formation in Summerville, Dorchester County, South Carolina. Nearly 3,500 teeth and dermal denticles are assigned to 29 species of sharks and rays, and our sample includes the oldest known occurrence of the whale shark, Rhincodon, as well as a new skate, Raja mccollumi sp. nov. The Chandler Bridge elasmobranch assemblage is comparable in species diversity to Chattian assemblages of Virginia and North Carolina, USA, and Germany. Notable absences from Germany include Rhincodon, Hemipristis, and Sphyrna zygaena, likely reflecting the influence of colder water on the North Sea Basin during the Chattian. Squaloids, pristiophoroids, and hexanchoids are known from Chattian deposits of the Albemarle Embayment (North Carolina), Salisbury Embayment (Virginia), and North Sea Basin, but these taxa are absent from the Chandler Bridge assemblage, perhaps because of shallow, warm water (20 to 25°C) conditions within the more southerly Charleston Embayment.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cranial morphology, systematics and succession of beavers from the middle Miocene Valentine Formation of Nebraska, USA
Autorzy:
Korth, W W
Powiązania:
https://bibliotekanauki.pl/articles/21878.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Miocene
beaver
systematics
Valentine Formation
paleontology
fauna succession
cranial morphology
USA
Castoridae
Barstovian
Clarendonian
Middle Miocene
Nebraska
Opis:
Previously, it was believed that there was a dramatic turn−over in the fauna of beavers (Rodentia, Castoridae) from the Barstovian to the Clarendonian from Nebraska. Stratigraphically controlled collections of fossil castorids from the Valentine Formation, which cross this boundary, now indicate that a complete change in the castorid fauna did not occur, but instead a more gradual change and replacement of earlier taxa with more advanced taxa occurred. The range of Eucastor tortus and Monosaulax skinneri is extended from late Barstovian into the latest Barstovian Devil’s Gulch Member and the range of the otherwise Clarendonian species of Prodipoides is extended downward into the late Barstovian Crookston Bridge Member. The skulls of Monosaulax skinneri and Eucastor valentinensis are described in detail for the first time. The cranial morphology of M. skinneri is primitive for Castoroidini and that of E. valentinensis is specialized for tooth−digging behavior as in the Nothodipoidini. A new genus, Temperocastor, is proposed for E. valentinensis based on its primitive morphology of the cheek teeth and derived cranial morphology. Temperocastor represents the most primitive nothodipoidine.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new diplodocoid sauropod dinosaur from the Upper Jurassic Morrison Formation of Montana, USA
Autorzy:
Harris, J D
Dodson, P.
Powiązania:
https://bibliotekanauki.pl/articles/22659.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
phylogenesis
Dicraeosauridae
Diplodocoidea
Upper Jurassic
dinosaur
Montana
Jurassic
paleobiogeography
Diplodocidae
USA
sauropod dinosaur
Dinosauria
Morrison Formation
paleontology
Opis:
A partial skeleton of a new sauropod dinosaur from the Upper Jurassic Morrison Formation (?Tithonian) of Montana is described. Suuwassea emilieae gen. et sp. nov. is diagnosed by numerous cranial, axial, and appendicular autapomorphies. The holotype consists of a premaxilla, partial maxilla, quadrate, braincase with partial skull roof, several partial and complete cranial and middle cervical, cranial dorsal, and caudal vertebrae, ribs, complete scapulocoracoid, humerus, partial tibia, complete fibula, calcaneus, and partial pes. It displays numerous synapomorphies of the Diplodocoidea, including characters of both the Diplodocidae (Apatosaurus + (Diplodocus + Barosaurus)) and Dicraeosauridae (Dicraeosaurus + Amargasaurus). Preliminary phylogenetic analysis indicates that Suuwassea is a diplodocoid more derived than rebbachisaurids but in a trichotomy with both the Diplodocidae and Dicraeosauridae. Suuwassea represents the first well−supported, North American, non−diplodocid representative of the Diplodocoidea and provides new insight into the origins of both the Diplodocidae and Dicraeosauridae.
Źródło:
Acta Palaeontologica Polonica; 2004, 49, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Palaeoecology of the Spathian Virgin Formation (Utah, USA) and its implications for the Early Triassic recovery
Autorzy:
Hofmann, R.
Hautmann, M.
Wasmer, M.
Bucher, H.
Powiązania:
https://bibliotekanauki.pl/articles/21319.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleoecology
Spathian Virgin Formation
Utah
USA
Early Triassic
Triassic
recovery
diversity
biotic recovery
mass extinction
Opis:
The Spathian (late Early Triassic) Virgin Formation of south−western Utah (USA) yields a comparatively diverse benthic fauna that flourished ~2 Ma after the end−Permian mass extinction. In this study, we present quantitative palaeoecological data, which are analysed in the context of depositional environments. This integrated approach helps to discriminate between effects of the end−Permian mass extinction event and local environmental factors on alpha diversity and ecological structure of the Virgin Fauna. Shallow subtidal environments yield the highest species richness and lowest dominance val− ues as recorded in two benthic associations, the Eumorphotis ericiusAssociation and the Protogusarella smithi Association, both ofwhich contain 20 benthic species (bivalves, gastropods, brachiopods, echinoderms, and porifers). Tidal inlet deposits yield a low diverse fauna (Piarorhynchella triassica Association) with a very high dominance of filter feeders adapted to high energy conditions.Another comparably low diverse fauna is recorded by the Bakevellia exporrecta Association, which occurs in deposits of the offshore transition zone,most likely reflecting unconsolidated substrates. A single sample contain− ing five bivalve species (Bakevellia costata Assemblage) is recorded from a marginal−marine setting. The Virgin fauna yields a bulk diversity of 30 benthic species (22 genera) of body fossils and 14 ichnogenera and, thus, represents the most di− verse marine bottom fauna known so far from the Early Triassic. Our results suggest that oceanographic conditions during the early Spathian enabled ecosystems to rediversify without major abiotic limitations. However, taxonomical differentia− tion between habitats was still low, indicating a time lag between increasing within−habitat diversity (alpha diversity) and the onset of taxonomical differentiation between habitats (beta diversity). We suggest that taxonomical habitat differentia− tion after mass extinction events starts only when within−habitat competition exceeds a certain threshold, which was not yet reached in the Spathian of the investigated area. This interpretation is an alternative to previous suggestions that the preva− lence of generalistic taxa in the aftermath of mass extinction events reflects protracted environmental stress. The onset of in− creasing beta diversity is a potential criterion for distinguishing two major recovery phases, the first ending with habitat satu− ration and the second ending with the completion of ecosystem differentiation.
Źródło:
Acta Palaeontologica Polonica; 2013, 58, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Palaeoecology of free-lying domal bryozoan colonies from the Upper Eocene of Southeastern USA
Autorzy:
McKinney, F K
Taylor, P.D.
Powiązania:
https://bibliotekanauki.pl/articles/22653.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
bryozoan colony
marine rock
Paleozoic
Eocene
USA
sedimentary rock
Upper Eocene
morphology
paleoecology
Bryozoa
Castle Hayne Formation
paleontology
Opis:
Dome−shaped cheilostome bryozoan colonies, most commonly about 2 cm in diameter, are common in Upper Eocene offshore deposits of southeastern North Carolina, USA.This colony−form is anachronistic in the Eocene, being more typical of Palaeozoic bryozoans.There are three types of domes: individual colonies of Parasmittina collum (Canu and Bassler), individual colonies of Osthimosia glomerata (Gabb and Horn) and multispecies intergrowths.The bryozoans grew laterally beyond initial shell substrata to become free−lying. P. collum colonies grew by local eruptive budding, forming subcolonies that extended radially over the underlying layer of zooids.Undersides of subcolonies that extended beyond the original substratum have basal exterior walls that are more commonly fouled by encrusters than is the upper side of the colony.By contrast, lateral growth of O. glomerata colonies was limited by size of the original substratum, subcolonies were not developed, and colony growth occurred by prolific frontal budding over the entire upper surface of the colony. Undersides of colonies beyond the substratum consist of the lateral interior walls of marginal zooids and are much less commonly fouled than are undersurfaces of P. collum.The upper surfaces of multispecies domes by definition are always fouled, and their undersurfaces are also commonly fouled.
Źródło:
Acta Palaeontologica Polonica; 2003, 48, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exceptional cameral deposits in a sublethally injured Carboniferous orthoconic nautiloid from the Buckhorn Asphalt Lagerstatte in Oklahoma, USA
Autorzy:
Seuss, B.
Mapes, R.H.
Klug, C.
Nutzel, A.
Powiązania:
https://bibliotekanauki.pl/articles/22348.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
cameral deposit
Carboniferous
orthoconic nautiloid
Buckhorn Asphalt
Oklahoma
USA
Nautiloidea
Pseudorthoceratidae
predation
sublethal damage
Opis:
The cameral and intrasiphonal deposits of a Pennsylvanian straight nautiloid (Pseudorthoceratidae) are studied in order to understand the formation of these deposits. The specimens from the Buckhorn Asphalt deposit (Oklahoma) are exceptionally preserved including original aragonite and microstructures. The specimen investigated survived a predation attempt and shows bite marks on the phragmocone. This is the second report of an ectocochleate cephalopod and first report of an orthoconic nautiloid which survived massive damage of conch and siphuncle. For the first time, a high−magnesium calcitic mineralogy of cameral deposits is documented. These deposits were formed in alternation with aragonite in a chamber which was perforated during the unsuccessful predation attempt. The animal formed the chamber deposits throughout its entire lifetime and the siphuncle played a major role in formation of the cameral deposits.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Catshark egg capsules from a Late Eocene deep-water methane-seep deposit in western Washington State, USA
Autorzy:
Kiel, S.
Peckmann, J.
Simon, K.
Powiązania:
https://bibliotekanauki.pl/articles/21852.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
catshark
egg capsule
fossil
Late Eocene
Eocene
deep water
methane-seep deposit
Washington State
USA
Elasmobranchia
Scyliorhinidae
taphonomy
exceptional preservation
collagen
Opis:
Fossil catshark egg capsules, Scyliorhinotheca goederti gen. et sp. nov., are reported from a Late Eocene deep−water methane−seep calcareous deposit in western Washington State, USA. The capsules are preserved three−dimensionally and some show mineralized remnants of the ribbed capsule wall consisting of small globular crystals that are embedded in a microsparitic matrix. The globules are calcitic, but a strontium content of 2400–3000 ppm suggests that they were origi− nally aragonitic. The carbonate enclosing the egg capsules, and the capsule wall itself, show 13C values as low as −36.5‰, suggesting that formation was induced by the anaerobic oxidation of methane and hence in an anoxic environ− ment. We put forward the following scenario for the mineralization of the capsule wall: (i) the collagenous capsules expe− rienced a sudden change from oxic to anoxic conditions favouring an increase of alkalinity; (ii) this led to the precipitation of aragonitic globules within the collagenous capsule wall; (iii) subsequently the remaining capsule wall was mineralized by calcite or aragonite; (iv) finally the aragonitic parts of the wall recrystallized to calcite. The unusual globular habit of the early carbonate precipitates apparently represents a taphonomic feature, resulting from mineralization mediated by an organic matrix. Taphonomic processes, however, are at best contributed to an increase of alkalinity, which was mostly driven by methane oxidation at the ancient seep site.
Źródło:
Acta Palaeontologica Polonica; 2013, 58, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New large leptictid insectivore from the Late Paleogene of South Dakota, USA
Autorzy:
Meehan, T.J.
Martin, L.D.
Powiązania:
https://bibliotekanauki.pl/articles/20697.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
new genus
new species
large leptictid insectivore
insectivore
Insectivora
Late Paleogene
South Dakota
USA
Mammalia
Leptictidae
Leptictis
Megaleptictis
Eocene
Oligocene
White River Group
skull
mandible
systematics
Opis:
From a skull and mandible, we describe a new genus and species of a primitive insectivore (Mammalia: Insectivora: Leptictida: Leptictidae). Its large body size and higher−crowned teeth indicate a different feeding ecology from other leptictid insectivores. With evidence of some heavy, flat wear on the molariform teeth, its shift in diet was likely to greater herbivory. Unlike the narrow snout of Blacktops, this new leptictid retains a broad snout, suggesting that small vertebrates were still important dietary components. The specimen was collected from the floodplain deposits of the lower or middle White River Group of South Dakota, which represent the latest Eocene to earliest Oligocene (Chadronian and Orellan North American Land Mammal “Ages”).
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On a new pygasterid (Echinoidea) from the Jurassic (Middle Lias) of Nevada, U.S.A.
O nowym przedstawicielu rodziny Pygasteridae Lambert, 1900 (Echinoidea) z liasu stanu Nevada (U.S.A.)
O novom predstavitele semejjstva Pygasteridae Lambert, 1900 (Echinoidea) iz lejjasa shtata Nevada (SShA)
Autorzy:
Jesionek-Szymanska, W.
Powiązania:
https://bibliotekanauki.pl/articles/22150.pdf
Data publikacji:
1970
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Źródło:
Acta Palaeontologica Polonica; 1970, 15, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new microconchid tubeworm from the Artinskian (Lower Permian) of central Texas, USA
Autorzy:
Wilson, M.A.
Vinn, O.
Yancer, T.E.
Powiązania:
https://bibliotekanauki.pl/articles/20377.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
Calcareous tubeworms are common in the Artinskian (Lower Permian) shale and limestone rocks of the Wichita−Albany Group in central Texas. In some units they form small reefs of budding tubes spreading outward from a common origin. These tubular fossils have been traditionally referred to as serpulids, but here we identify them as microconchids (Helicoconchus elongatus gen. et sp. nov.) These microconchids are unusual because of their greatly elongated impunctate tubes with centrally pitted diaphragms. They also show two types of budding: lateral with small daughter tubes that begin as small coils, and binary fission that produced two daughter tubes of equal diameters. These microconchids flourished in shallow marine environments with a fauna dominated by mollusks, echinoids, and foraminifera.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 46

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