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Tytuł:
Exploring the limits of morphospace: ontogeny and ecology of Late Visean ammonoids from the Tafilalt, Morocco
Autorzy:
Klug, C.
De Baets, K.
Korn, D.
Powiązania:
https://bibliotekanauki.pl/articles/22457.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleoecology
morphospace
ontogenesis
ecology
Late Visean
ammonoid
Ammonoidea
Morocco
Opis:
Early late Viséan ammonoid assemblages in Morocco are composed of diverse and well-preserved specimens. The material was found in a plain in the Tafilalt (eastern Anti-Atlas). Here, we describe mass-occurrences of juvenile specimens, in which subadult and adult specimens occur in low numbers. The juveniles of some species display a conch morphology that differs fundamentally from the adult stages. Accordingly, we emend the species diagnoses of Goniatites lazarus as well as Calygirtyoceras darkaouaense, introduce the species Entogonites bucheri sp. nov., and discuss possible ecological implications of the morphologic changes throughout ontogeny. In particular, we compare the changes in conch morphology through ontogeny in the light of Pareto Optimiality according to which the morphology of organisms would fill a polygon or polyhedron in morphospace. Data points in one of the vorteces of the polyhedron indicate optimisation for the corresponding task. Although shape is not a proof of function, it appears plausible that juvenile conchs were selected rather for compactness while adult conchs were positively selected for conchs with improved hydrodynamic properties. This appears plausible because at small conch diameters, swimming movements will not suffice for effective translocation and a planktonic mode of life is likely.
Źródło:
Acta Palaeontologica Polonica; 2016, 61, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The origin of ammonoid locomotion
Autorzy:
Klug, C
Korn, D.
Powiązania:
https://bibliotekanauki.pl/articles/21156.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
phylogenesis
Bactritida
ontogenesis
Ammonoidea
conch
coiling
Devonian
paleontology
locomotion
ammonoid
Opis:
Evolution of the coiled ammonoid conch from the uncoiled bactritid conch was probably coupled with changes in manoeuvrability and swimming velocity. The gradual transformation of uncoiled to coiled ammonoid conchs has essential functional consequences. The radical change in conch geometry during phylogeny but also in ontogeny of early ammonoids implies a shift of the aperture from an original roughly downward, via a downward oblique and an upward oblique to an upward orientation, presuming a neutrally buoyant condition of the ammonoid animal. Similar trends were reconstructed for the three main ammonoid lineages in the Middle Devonian, the agoniatitid, the anarcestid, and the tornoceratid lineages. This allowed an increase in manoeuvrability and in the maximum horizontal swimming speed.
Źródło:
Acta Palaeontologica Polonica; 2004, 49, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Early Cambrian [Botomian] stem group brachiopod Mickwitzia from Northeast Greenland
Autorzy:
Skovsted, C B
Holmer, L.E.
Powiązania:
https://bibliotekanauki.pl/articles/22580.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
ontogenesis
brachiopod
shell structure
Greenland
Cambrian
Mickwitzia
Brachiopoda
paleontology
Botomian
Opis:
The problematic brachiopod Mickwitzia Schmidt, 1888 is re−described based on new material of M. cf. occidens Walcott, 1908 from the Early Cambrian (Botomian) Bastion and Ella Island formations of Northeast Greenland. Etched material demonstrates that Mickwitzia has a lingulid−like juvenile (“larval”) shell with trails of nick−points, reflecting the movement of marginal setae. Juvenile and early mature ventral valves have a lingulid−like pseudointerarea with a pedicle groove. The shell of M. cf. occidens is only partially phosphatic, in particular around the juvenile–early mature shell in both valves. The phosphatic shell includes at least two types of cylindrical structures: (1) slender columns identical with the columns of acrotretoid brachiopods and (2) relatively thicker tubes which may be open to the exterior surface and have internal striations (on the ventral pseudointerarea). The striations are most likely imprints of microvilli and these tubes can be inferred to have contained setae. The thinner linguliform columns and thicker setigerous striated tubes are considered to be homologous with identical structures in the sellate and mitral sclerites of the problematic Micrina, which has been identified as a probable primitive stem group of the Brachiopoda. Mickwitzia represents a more derived member of the stem group Brachiopoda.
Źródło:
Acta Palaeontologica Polonica; 2003, 48, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Givetian (Middle Devonian) sharks from Cairo, New York (USA): Evidence of early cosmopolitanism
Autorzy:
Potvin-Leduc, D.
Cloutier, R.
Landing, E.
Hernick, L.V.
Mannolini, F.
Powiązania:
https://bibliotekanauki.pl/articles/945591.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Chondrichthyes
Elasmobranchii
Antarctilamnidae
Omalodontiformes
taxonomy
ontogenesis
paleobiogeography
Devonian
North America
Opis:
Whereas cosmopolitan distribution patterns are established for many Late Devonian vertebrates (e.g., placoderms, onychodontiforms), few palaeobiogeographic studies have considered chondrichthyans. Recent discoveries of shark material demonstrate that some chondrichthyans were cosmopolitan by the Middle Devonian. Abundant Givetian microremains have been recovered from the Cairo quarry in eastern New York State, USA. These include teeth of two shark species with Gondwanan affinities, the omalodontid Portalodus mannoliniae sp. nov. and the antarctilamnid Wellerodus priscus. Abundant teeth of P. mannoliniae sp. nov. are characterized by a smooth diplodont crown, polarized cusps, and a labially oriented base. The teeth demonstrate monognathic heterodonty. The juvenile morph is distinguished from the adult by smaller size, slender cusps, and variation in the shape of the base. W. priscus is represented by rare juvenile teeth. Two groups of scales that show affinity to material from northern (Spain) and East Gondwana (Antarctica) are tentatively attributed to the two described species. Antarctilamnid distribution suggests a north Gondwanan origin and a colonization of the margin of the landmass before dispersing to Laurentia by the Middle Devonian. This material further indicates that vertebrate global dispersal was initiated by the Middle Devonian, and emphasizes earlier palaeogeographic interpretations that the Middle Devonian “Hamilton fauna” of North American Laurussia originated in the Early Devonian in South American Gondwana.
Źródło:
Acta Palaeontologica Polonica; 2015, 60, 1; 183-200
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ontogeny of a new cyrtosymboline trilobite from the Famennian of Morocco
Autorzy:
Loresey-Aubril, R
Feist, R.
Powiązania:
https://bibliotekanauki.pl/articles/20463.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
trilobite
cyrtosymboline trilobite
Famennian
Trilobita
ontogenesis
Proetoidea
Cyrtosymbolinae
protaspis
remains
Morocco
paleontology
Opis:
Abundant trilobite remains were recovered from late mid−Famennian marlstones from various sites in Eastern Tafilalet, southeast Morocco. All belong to a single taxon previously identified as Cyrtosymbole (Waribole) prima. This taxon is designated the type species of Osmolskabole gen. nov. A redefinition of this species, including the description of newly discovered, disarticulated exuviae both in limestone and silicified state of preservation, is given. In particular, silicified sclerites of various sizes allow the first complete growth series of a cyrtosymboline proetid to be presented. The close morphological resemblance of its protaspid stages to known proetoid larvae emphasizes the homogeneity of the early ontogeny in this superfamily. The Famennian proetoid anaprotaspis is also of comparable size to that of other Devonian proetoid larvae. However, their size−range is much less than that observed in Carboniferous larvae. This suggests that the survival of proetoid trilobites at the Frasnian−Famennian Kellwasser crisis did not result from a modification of the developmental strategy, as it might have been the case at the terminal Devonian extinction event. Moreover, O. prima possesses a plectrum from the metaprotaspid to the mid meraspid periods. This implies that the natant hypostomal condition is not steadily acquired early in the ontogeny of the Proetida. Thus we preclude the use of this character in the diagnosis of this order.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Additional observations on the Jurassic belemnoids of Poland
Dodatkowe badania nad belemnitami jurajskimi w Polsce
Dopolnitel'nye issledovanija jurskikh belemnitov v Pol'she
Autorzy:
Pugaczewska, H.
Powiązania:
https://bibliotekanauki.pl/articles/22567.pdf
Data publikacji:
1965
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
Jurassic
belemnoid
Belemnopsis wiekensis
new species
Belemnopsinae
ontogenesis
structure
rostrum
Polska
Źródło:
Acta Palaeontologica Polonica; 1965, 10, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new genus of patellogastropod with unusual protoconch from Miocene of Paratethys
Autorzy:
Anistratenko, O Y
Bandel, K.
Anistratenko, V.V.
Powiązania:
https://bibliotekanauki.pl/articles/21085.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Tectura zboroviensis
Miocene
ontogenesis
Patellogastropoda
protoconch
Tectura pseudolaevigata
Tectura angulata
morphology
teleoconch
paleontology
Opis:
The protoconch and teleoconch morphology of “Tectura” angulata, “Tectura” pseudolaevigata from the Sarmatian and “Tectura” zboroviensisfrom the Badenian of the Eastern Paratethys have been studied in detail for the first time. The new genus Blinia is established for Sarmatian species which are characterized by a protoconch indicative of lecithotrophic type of early development lacking even a short free−swimming larval stage. In contrary the protoconch of Badenian “Tectura” zboroviensis demonstrates features of the shell typical for planktonic larva. The shape and proportions of a pancake−like protoconch in Blinia species suggest the development of young snails in brood pouch in the mantle cavity of maternal individual. The independence of Blinia gen. nov. from other Patellogastropoda such as Tectura, Patella, and Helcion is supported also by characteristics of shell structure. Typical patellogastropod protoconchs are present in the Badenian and the first half of the early Sarmatian and the protoconchs indicating lecithotrophic development are observed in patellogastropods only from the younger half of early Sarmatian and middle Sarmatian deposits. The change in ontogenetic strategy occurred during time of lowered salinity in the Paratethys. We suggest that the snails’ reproductive strategy was modified and free larval life was suppressed to cope with salinity change in the ambient water.
Źródło:
Acta Palaeontologica Polonica; 2006, 51, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The type species of Cyrtosymbole and the oldest [Famennian] cyrtosymboline trilobites
Autorzy:
Feist, R
Lerosey-Aubril, R.
Powiązania:
https://bibliotekanauki.pl/articles/22254.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
cyrtosymboline trilobite
trilobite
Famennian
Trilobita
Cyrtosymbole
ontogenesis
Cyrtosymbolinae
Proetidae
Devonian
Dechenella escoti
paleontology
Opis:
The hitherto poorly known type species of Cyrtosymbole, i.e., Dechenella escoti, is redescribed on the basis of an abundant new material recovered from the early Famennian Lower Griotte Limestone Formation at La Tourière, near Cabrières, southern France. It includes sclerites (hypostome, librigenae, thoracic segments and external surface of the pygidium) that previously were either unknown, or represented by poorly preserved and incomplete specimens, together with a full suite of post−protaspid growth stages. The latter has revealed that certain characters, in particular the preglabellar region and postocular facial sutures, show marked changes between the early and late holaspid stages. In the past, some species have been based on immature specimens; for example the lectotype of C. escoti is an early holaspis, and the characters that it displays have been regarded as diagnostic of the genus. For confident specific assignments in cyrtosymboline trilobites it is important, therefore, to have to hand sufficient material, including late holaspids. A revised diagnosis of Cyrtosymbole is given, and only those species that share diagnostic adult characters with C. escoti are assigned to it. Insights into early growth development exemplified by C. escoti and allies corroborate the attribution of the Cyrtosymbolinae to the Proetidae.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Morphology and ontogeny of the Cambrian edrioasteroid echinoderm Cambraster cannati from western Gondwana
Autorzy:
Zamora, S.
Sumrall, C.D.
Vizcaino, D.
Powiązania:
https://bibliotekanauki.pl/articles/21463.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Echinodermata
Edrioasteroidea
paleobiology
Cambrian
Spain
France
morphology
ontogenesis
edrioasteroid echinoderm
echinoderm
Cambraster cannati
Gondwana
Opis:
A review of the Cambrian edrioasteroid echinoderm Cambraster cannati is made based on new collections from the Iberian Chains (NE Spain) and Montagne Noire (France). New morphological data include a completely articulated oral area and details of ambulacra. Specimens ranging from 4 to 26 mm in diameter provide detailed information concerning the full ontogeny. Important changes through ontogeny mainly affect the marginal ring and the plating pattern of the aboral surface. Comparison with other species of Cambrasterindicates that the aboral surface of Cambraster tastudorum from Australia shows strong resemblance to juvenile specimens of C. cannati. Cambraster cannati was attached directly to the substrate and inhabited relatively high energy, offshore environments from the west margin of Gondwana. Abnormalities in the skeleton are described for the first time in a Cambrian edrioasteroid.
Źródło:
Acta Palaeontologica Polonica; 2013, 58, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Early ontogeny of Jurassic bakevelliids and their bearing on bivalve evolution
Autorzy:
Malchus, N
Powiązania:
https://bibliotekanauki.pl/articles/22830.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
phylogenesis
Pteriomorphia
Bakevelliidae
shell
bakevelliid
larva shell
Jurassic
bivalve
ontogenesis
Bivalvia
evolution
larva
paleontology
Opis:
Larval and earliest postlarval shells of Jurassic Bakevelliidae are described for the first time and some complementary data are given concerning larval shells of oysters and pinnids. Two new larval shell characters, a posterodorsal outlet and shell septum are described. The outlet is homologous to the posterodorsal notch of oysters and posterodorsal ridge of arcoids. It probably reflects the presence of the soft anatomical character post−anal tuft, which, among Pteriomorphia, was only known from oysters. A shell septum was so far only known from Cassianellidae, Lithiotidae, and the bakevelliid Kobayashites. A review of early ontogenetic shell characters strongly suggests a basal dichotomy within the Pteriomorphia separating taxa with opisthogyrate larval shells, such as most (or all?) Praecardioida, Pinnoida, Pterioida (Bakevelliidae, Cassianellidae, all living Pterioidea), and Ostreoida from all other groups. The Pinnidae appear to be closely related to the Pterioida, and the Bakevelliidae belong to the stem line of the Cassianellidae, Lithiotidae, Pterioidea, and Ostreoidea. The latter two superfamilies comprise a well constrained clade. These interpretations are consistent with recent phylogenetic hypotheses based on palaeontological and genetic (18S and 28S mtDNA) data. A more detailed phylogeny is hampered by the fact that many larval shell characters are rather ancient plesiomorphies.
Źródło:
Acta Palaeontologica Polonica; 2004, 49, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A giant skull of the temnospondyl Xenotosuchus africanus from the Middle Triassic of South Africa and its ontogenetic implications
Autorzy:
Damiani, R
Powiązania:
https://bibliotekanauki.pl/articles/21570.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Temnospondyli
Triassic
paleontology
ontogenesis
Africa
Middle Triassic
variation
temnospondyl form
Xenotosuchus africanus
South Africa
skull
Opis:
A previously unreported large skull of the mastodonsaurid temnospondyl Xenotosuchus africanus, from the Cynognathus Assemblage Zone (Early to Middle Triassic) of the Beaufort Group, Karoo Basin of South Africa, is described. The species is plesiomorphic in most aspects of its cranial anatomy, and only one autapomorphy is tentatively identified herein, namely contact between the left and right exoccipitals posterior to the parasphenoid. The new specimen permits recognition of a growth series for X. africanus from sub−adult (all previously known specimens) to fully adult (new specimen) stages. Ontogenetic changes associated with this include changes in skull proportions, and changes in the morphology of the lacrimal flexure, frontal, postfrontal, cultriform process and body of the parasphenoid, and the transvomerine tooth row.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new Arctic hadrosaurid from the Prince Creek Formation (lower Maastrichtian) of northern Alaska
Autorzy:
Mori, H.
Druckenmiller, P.S.
Erickson, G.M.
Powiązania:
https://bibliotekanauki.pl/articles/23525.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new species
Arctic
hadrosaurid
Dinosauria
Hadrosauridae
Saurolophinae
Edmontosaurini
ontogenesis
Cretaceous
Prince Creek Formation
Maastrichtian
Alaska
Opis:
The Liscomb bonebed in the Price Creek Formation of northern Alaska has produced thousands of individual bones of a saurolophine hadrosaurid similar to Edmontosaurus; however, the specific identity of this taxon has been unclear, in part because the vast majority of the remains represent immature individuals. In this study, we address the taxonomic status of the Alaskan material through a comparative and quantitative morphological analysis of juvenile as well several near adult-sized specimens with particular reference to the two known species of Edmontosaurus, as well as a cladistic analysis using two different matrices for Hadrosauroidea. In the comparative morphological analysis, we introduce a quantitative method using bivariate plots to address ontogenetic variation. Our comparative anatomical analysis reveals that the Alaskan saurolophine possesses a unique suite of characters that distinguishes it from Edmontosaurus, including a premaxillary circumnarial ridge that projects posterolaterally without a premaxillary vestibular promontory, a shallow groove lateral to the posterodorsal premaxillary foramen, a relatively narrow jugal process of the postorbital lacking a postorbital pocket, a relatively tall maxilla, a relatively gracile jugal, a more strongly angled posterior margin of the anterior process of the jugal, wide lateral exposure of the quadratojugal, and a short symphyseal process of the dentary. The cladistic analyses consistently recover the Alaskan saurolophine as the sister taxon to Edmontosaurus annectens + Edmontosaurus regalis. This phylogenetic assessment is robust even when accounting for ontogenetically variable characters. Based on these results, we erect a new taxon, Ugrunaaluk kuukpikensis gen. et sp. nov. that contributes to growing evidence for a distinct, early Maastrichtian Arctic dinosaur community that existed at the northernmost extent of Laramidia during the Late Cretaceous.
Źródło:
Acta Palaeontologica Polonica; 2016, 61, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Miocene cyclopid copepod from a saline paleolake in Mojave, California
Autorzy:
Holynska, M.
Leggitt, L.
Kotov, A.A.
Powiązania:
https://bibliotekanauki.pl/articles/20781.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Miocene
cyclopid copepod
copepod
Copepoda
Cyclopidae
ontogenesis
biogeography
Barstow Formation
saline lake
paleontology
Mojave Desert
California
Opis:
There are remarkably few direct fossil records of Copepoda, which implies that current estimates of the lineage divergence times and inferences on the historical biogeography remain highly dubious for these small-sized crustaceans. The Cyclopidae, a predominantly freshwater copepod family with 1000+ species and distributed worldwide, has no fossil record at all. Recent collections from the middle Miocene Barstow Formation in Southern California resulted in ample material of finely preserved cyclopid fossils, including both adult and larval stages. To document the antennulary setation pattern in the adult and copepodid instars we used a coding system that is coherent between sexes and developmental stages. The majority of the cyclopid fossils, coming from saline lake environment, represent the modern genus Apocyclops, a euryhaline, thermophilic group occurring both in the New World and Old World. A new species Apocyclops californicus is described, based on the short medial spine and spiny ornamentation of the free segment of leg 5, spinule ornamentation of pediger 5, and well-developed protuberances of the intercoxal sclerite of leg 4. The presence of antennal allobasis and the features of the swimming legs unambiguously place the Miocene Apocyclops in the A. panamensis- clade, a predominantly amphi-Pacific group. The middle Miocene fossils with clear affinities to a subgroup of Apocyclops imply an early Miocene or Paleogene origin of the genus. Based on the geographic patterns of the species richness and morphology in Apocyclops and its presumed closest relative, genus Metacyclops, we hypothesize that: (i) the ancestor of Apocyclops, similar in morphology to some cave-dweller Metacyclops occurring today in the peri-Mediterranean region, might have arrived in North America from Europe via the Thulean North Atlantic bridge in the late Paleocene–early Eocene; (ii) Eocene termination of the Thulean land connection might have resulted in the divergence of Apocyclops from the Metacyclops stock.
Źródło:
Acta Palaeontologica Polonica; 2016, 61, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new species of the sauropsid reptile Nothosaurus from the Lower Muschelkalk of the western Germanic Basin, Winterswijk, The Netherlands
Autorzy:
Klein, N.
Albers, P.C.H.
Powiązania:
https://bibliotekanauki.pl/articles/22006.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new species
sauropsid reptile
Nothosaurus
Lower Muschelkalk
Germanic Basin
Winterswijk town
Netherlands,The
paleobiology
Sauropterygia
ontogenesis
Opis:
A nothosaur skull recently discovered from the Lower Muschelkalk (early Anisian) locality of Winterswijk, The Netherlands, represents at only 46 mm in length the smallest nothosaur skull known today. It resembles largely the skull morphology of Nothosaurus marchicus. Differences concern beside the size, the straight rectangular and relative broad parietals, the short posterior extent of the maxilla, the skull proportions, and the overall low number of maxillary teeth. In spite of its small size, the skull can not unequivocally be interpreted as juvenile. It shows fused premaxillae, nasals, frontals, and parietals, a nearly co−ossified jugal, and fully developed braincase elements, such as a basisphenoid and massive epipterygoids. Adding the specimen to an existing phylogenetic analysis shows that it should be assigned to a new species, Nothosaurus winkelhorsti sp. nov., at least until its juvenile status can be unequivocally verified. Nothosaurus winkelhorsti sp. nov. represents, together with Nothosaurus juvenilis, the most basal nothosaur, so far.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Late Famennian stromatoporoids from Debnik Anticline, southern Poland
Autorzy:
Wolniewicz, P
Powiązania:
https://bibliotekanauki.pl/articles/19981.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
Famennian
Late Famennian
stromatoporoid
Polska
Porifera
ontogenesis
Quasiendothyra communis
Clathrodictyida
Gerronostroma
Stylostroma
Labechiida
Gerronostroma raclaviense
Stromatoporoidea
Opis:
Famennian Stromatoporoidea from the Quasiendothyra communis Foraminiferal Zone and slightly younger strata from the Dębnik anticline, southern Poland, form a succession of three consecutive assemblages. Assemblages 1 and 3 consist of representatives of the order Clathrodictyida, while assemblage 2 is dominated by the order Labechiida. The clathrodictyids are represented by the genus Gerronostroma, and labechiids are represented by the genus Stylostroma. Species assigned here to the genus Gerronostroma show a network of amalgamated pillars in the central part of the columns, a feature regarded by previous authors as typical of the genus Clavidictyon. Two new species, Stylostroma multiformis sp. nov. and Gerronostroma raclaviense sp. nov., are described. Stromatoporoids from southern Poland differ from the Famennian fauna of western Europe, showing affinity to eastern European and Siberian Stromatoporoidea.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 2; 337-350
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł

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