Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "testudines" wg kryterium: Temat


Wyświetlanie 1-12 z 12
Tytuł:
A basal eucryptodiran turtle 'Sinemys' efremovi [-Waguia efremovi] from the Early Cretaceous of China
Autorzy:
Danilov, I G
Sukhanov, V.B.
Powiązania:
https://bibliotekanauki.pl/articles/21804.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Early Cretaceous
Cretaceous
Testudines
turtle
China
eucryptodiran turtle
Junggar Basin
Macrobaenidae
Eucryptodira
Wuguia efremovi
Sinemys efremovi
paleontology
Opis:
A reexamination of the type material (two specimens considered for a long time lost) of the poorly known turtle “Sinemys” efremovi Khosatzky, 1996 from the Early Cretaceous Tugulu Group of northwest China, allows us to present new observations, images, and taxonomic conclusions about these important specimens. We conclude that: (1) “S.” efremovi is referrable to the basal eucryptodire genus Wuguia Matzke, Maisch, Pfretzschner, Sun, and Stöhr, 2004 based on a small size (up to 150 mm in shell length), absence of the nuchal emargination, presence of additional ossifications in the suprapygal region of the carapace and similar plastral proportions with relatively long bridges (35−45% of the plastron width), and a narrow and elongated posterior lobe; (2) “S.” efremovi is a senior subjective synonym of Dracochelys wimani Maisch, Matzke, and Sun, 2003, another species recently described from the Tugulu Group. As construed here, Wuguia includes two species: W. efremovi (Khosatzky, 1996) and W. hutubeiensis Matzke, Maisch, Pfretzschner, Sun, and Stöhr, 2004. New diagnoses for these taxa are given.
Źródło:
Acta Palaeontologica Polonica; 2006, 51, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carapace bone histology in the giant pleurodiran turtle Stupendemys geographicus: phylogeny and function
Autorzy:
Scheyer, T M
Sanchez-Villagra, M.R.
Powiązania:
https://bibliotekanauki.pl/articles/20658.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
bone histology
Pleurodira
phylogenesis
bone analysis
Miocene
Stupendemys geographicus
Pelomedusoides
bone microstructure
giant pleurodiran turtle
Testudines
Bothremydidae
Podocnemidae
paleontology
Opis:
Stupendemys geographicus (Pleurodira: Pelomedusoides: Podocnemidae) is a giant turtle from the Miocene of Venezuela and Brazil. The bone histology of the carapace of two adult specimens from the Urumaco Formation is described herein, one of which is the largest of this species ever found. In order to determine phylogenetic versus scaling factors influencing bone histology, S. geographicus is compared with related podocnemid Podocnemis erythrocephala, and with fossil and Recent pelomedusoides taxa Bothremys barberi, Taphrosphys sulcatus, “Foxemys cf. F. mechinorum”, and Pelomedusa subrufa. Potential scaling effects on bone histology were further investigated by comparison to the Pleistocene giant tortoise Hesperotestudo (Caudochelys) crassiscutata and the Late Cretaceous marine protostegid turtle Archelon ischyros. A diploe structure of the shell with well developed external and internal cortices framing interior cancellous bone is plesiomorphic for all sampled taxa. Similarly, the occurrence of growth marks in the shell elements is interpreted as plesiomorphic, with the sampled neural elements providing the most extensive record of growth marks. The assignment of S. geographicus to the Podocnemidae was neither strengthened nor refuted by the bone histology. A reduced thickness of the internal cortex of the shell elements constitutes a potential synapomorphy of the Bothremydidae. S. geographicus and H. crassiscutata both express extensive weight−reduction through lightweightconstruction while retaining form stability of the shell. The bone histology of A. ischyros presents features likely related to an open marine lifestyle.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The cranial anatomy of the Early Jurassic turtle Kayentachelys aprix
Autorzy:
Sterli, J.
Joyce, W.G.
Powiązania:
https://bibliotekanauki.pl/articles/22757.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
cranial anatomy
Cryptodira
Testudines
Jurassic
Early Jurassic
turtle
Kayentachelys aprix
evolution
fossil record
Kayenta Formation
Arizona
paleontology
systematics
Opis:
The fossil turtle Kayentachelys aprix is known from Early Jurassic sediments of the Kayenta Formation, Arizona, USA. The detailed description of this taxon’s cranium offered in this paper demonstrates that this turtle presents a mixture of primitive and derived character states. Among others, the presence of an interpterygoid vacuity, a basipterygoid process, a prootic that is exposed in ventral view, and a foramen posterius canalis carotici interni that is formed entirely by the basisphenoid are generally considered primitive for turtles. On the other hand, the presence of an undivided apertura narium, a well developed cavum tympani, an incipient cavum postoticum, and an unpaired vomer are considered to be derived. Kayentachelys aprix has previously been hypothesized to be the oldest stem cryptodiran turtle because of the presence of a flat, vertical plate on the processus pterygoideus externus, and the presence of a processus trochlearis oticum. However, the presence of these characters cannot be confirmed in the available specimens. Other putative stemcryptodiran characters, such as the prefrontal−vomer contact and the presence of an epipterygoid, are herein corroborated as being symplesiomorphies, because they generally appear to be present in basal turtles.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The description and phylogenetic position of a new nanhsiungchelyid turtle from the Late Cretaceous of Mongolia
Autorzy:
Sukhanov, V.B.
Danilov, I.G.
Syromyatnikova, E.V.
Powiązania:
https://bibliotekanauki.pl/articles/21943.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
description
phylogenetic position
new species
nanhsiungchelyid turtle
Kharakhutulia kalandadzei
turtle
Late Cretaceous
Mongolia
Kharakhutulia
paleontology
Nanhsiungchelyidae
Cryptodira
Testudines
Upper Cretaceous
Opis:
This paper describes a new nanhsiungchelyid turtle, Kharakhutulia kalandadzei gen. et sp. nov., based on two partial shells and additional shell fragments from the lower part of the Bainshire Formation (Upper Cretaceous, Cenomanian–lower Turonian) of the Khara Khutul locality of Eastern Mongolia. Our phylogenetic analysis places Kharakhutulia kalandadzei as the most basal member of the Nanhsiungchelyidae and suggests new relationships within this group. Previously reported nanhsiungchelyid specimens from the Khara Khutul are reassigned to Nanhsiungchelyidae indet. and Hanbogdemyssp. indet. Thus the Khara Khutul includes at least two valid taxa of nanhsiungchelyids. Our analysis of the nanhsiungchelyid record in Asia shows that other localities have only a single representative of this clade, making Khara Khutul a unique site. The basal phylogenetic position of Kharakhutulia kalandadzei emphasizes the importance of the study of this and other Cenomanian–Turonian localities of Asia to better understand the basal diversification of the Nanhsiungchelyidae.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new freshwater basal eucryptodiran turtle from the Lower Cretaceous of Spain
Autorzy:
Perez-Garcia, A.
De La Fuente, M.S.
Ortega, F.
Powiązania:
https://bibliotekanauki.pl/articles/20420.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new genus
new species
freshwater turtle
eucryptodiran turtle
Lower Cretaceous
Cretaceous
paleontology
Spain
Testudines
Eucryptodira
Barremian
Las Hoyas
Opis:
A freshwater turtle from the lithographic limestone of Las Hoyas (Barremian of Cuenca, Spain) is described as a new genus and species of Eucryptodira, Hoyasemys jimenezi. The holotype consists of the skull, lower jaw, carapace, plastron, vertebral column, pectoral and pelvic girdle remains, and foreand hindlimbs. Hoyasemys jimenezi gen. et sp. nov. is characterized by three pairs of blind oblique depressions on the ventral surface of the basisphenoid, and a character combination composed, among others, of the articulation between the fourth and fifth cervical vertebrae through a cotyle in the fourth and a condyle in the fifth, amphicoelous caudal centra, and most digits of manus and pes with three elongated phalanges. This study allows clarification of the systematic position of a species of uncertain affinity often identified as “chelydroid” in appearance. A phylogenetic analysis shows Hoyasemys jimenezi gen. et sp. nov. forms a monophyletic group with Judithemys sukhanovi, Dracochelys bicuspis, Sinemys lens, and Ordosemys leios, collectively the sister group of crown Cryptodira.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The European Early Cretaceous cryptodiran turtle Chitracephalus dumonii and the diversity of a poorly known lineage of turtles
Autorzy:
Perez-Garcia, A.
Powiązania:
https://bibliotekanauki.pl/articles/21609.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Europe
Lower Cretaceous
cryptodiran turtle
turtle
Chitracephalus dumonii
animal diversity
Testudines
Eucryptodira
Cryptodira
Cretaceous
Belgium
Spain
synonym
paleontology
phylogenetic analysis
systematics
holotype
Salasemys pulcherrima
Opis:
Chitracephalus dumonii was named based on some of the most complete turtle remains from the Lower Cretaceous of Europe, and yet the taxon has barely been mentioned since. Indeed, new specimens were erroneously attributed to a new taxon, “Salasemys pulcherrima”. The synonymy is recognized here, and this extends the geographical range of this turtle and provides examples of individuals at different stages of ontogenetic development. The peculiar structure of its shell, and its ontogenetic development, are unique to this taxon. The systematic position of C. dumonii was previously unclear, usually being referred to Testudinata incertae sedis. Here, it is placed in a cladistic analysis, which shows that C. dumonii, and the recently described Hoyasemys jimenezi form part of a Lower Cretaceous European clade of Cryptodira that includes “macrobaenid”, “sinemydid”, and panchelonioidean turtles.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new turtle species of Brodiechelys from the Early Cretaceous of Spain: Systematic and palaeobiogeographic implications
Autorzy:
Perez-Garcia, A.
Gasaulla, J.M.
Ortega, F.
Powiązania:
https://bibliotekanauki.pl/articles/946018.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
testudines
pan-cryptodira
xinjiangchelyidae
brodiechelys
cretaceous
europe
spain
Opis:
Brodiechelys brodiei is an Early Cretaceous turtle from Great Britain, the only species of the genus. This taxon has been shown in recent phylogenies to be closely related to Xinjiangchelyidae and therefore could be the only representative of this group in Europe. Here, we present several specimens from the Early Cretaceous Maestrazgo Basin, in the Iberian Range of Spain attributed to the British genus, and to a new species, Brodiechelys royoi. This discovery shows that, as previously observed with terrestrial turtles, some freshwater turtle taxa had a wide European distribution during the Early Cretaceous, being present in both Britain and the Iberian Peninsula. This study sheds new light on the phylogenetic position of this enigmatic genus, supporting its attribution to Xinjiangchelyidae, a clade whose presence has been previously confirmed exclusively from the Middle Jurassic to Early Cretaceous of Asia. We propose that another recently identified taxon from the Iberian Peninsula (i.e., Larachelus morla) is also a member of this clade. Recent studies have identified several continental taxa of the clade that included the members of “Macrobaenidae” and “Sinemydidae” in Europe. This study provides new evidence of close relationships between the Early Cretaceous turtle faunas from Europe and Asia.
Źródło:
Acta Palaeontologica Polonica; 2014, 59, 2; 333-342
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new soft-shelled trionychid turtle of the genus Khunnuchelys from the Upper Cretaceous Bostobe Formation of Kazakhstan
Autorzy:
Danilov, I.G.
Vitek, N.S.
Averianov, A.O.
Glinskiy, V.N.
Powiązania:
https://bibliotekanauki.pl/articles/945569.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
new species
soft-shelled turtle
Testudines
Trionychidae
Trionychia
Khunnuchelys lophorhothon
Upper Cretaceous
Cretaceous
Bostobe Formation
Kazakhstan
Opis:
Previously unpublished trionychid turtle material from the Upper Cretaceous (Santonian–lower Campanian) Bostobe Formation from the Baybishe and Baykhozha localities in Kazakhstan is described. The material represents a new species of Khunnuchelys, a large, skull-based clade of Cretaceous Asian trionychids. Concordant with other partial skulls and fragmentary specimens described previously, Khunnuchelys lophorhothon sp. nov. has the unusual features of a beaklike maxilla and a vaulted, expanded triturating surface. In addition, the specimens reveal novel features including a constricted skull roof. Although estimates of the length of the carapace differ depending on estimation method, the skull belonged to a turtle of comparable size to the shell-based species “Trionyx” kansaiensis from the same formation. It is likely that K. lophorhothon and “T.” kansaiensis are synonymous, but this can be proved only by a find of associated skull and shell material.
Źródło:
Acta Palaeontologica Polonica; 2015, 60, 1; 155-161
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Decompression syndrome and diving behavior in Odontochelys, the first turtle
Autorzy:
Rothschild, B.M.
Naples, V.
Powiązania:
https://bibliotekanauki.pl/articles/945596.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Testudines
Odontochelys semitestacea
turtle
diving behaviour
bone
pathology
avascular necrosis
osteonecrosis zob.avascular necrosis
bone infarction zob.avascular necrosis
aseptic necrosis zob.avascular necrosis
ischaemic bone necrosis zob.avascular necrosis
Triassic
Late Triassic
China
Opis:
Odontochelys semitestacea, the oldest known turtle, from the Late Triassic of China, shows a pathology. Sharply defined, focal depressions were noted on the articular surfaces of both humeri, documenting avascular necrosis. Diving habits of Mesozoic marine reptiles have been characterized on the basis of this localized form of bone death attributed to decompression syndrome. Pursuit by a predator was likely the cause of dangerously rapid depth changes by swimming turtles. The prevalence of avascular necrosis decreased geometrically from the Cretaceous to the Pleistocene. This study suggests that the habit of repetitive diving in turtles was already present in the Late Triassic, but that protective physiological and behavioral adaptations had not yet evolved.
Źródło:
Acta Palaeontologica Polonica; 2015, 60, 1; 163-167
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unusual shell anatomy and osteohistology in a new Late Cretaceous panchelid turtle from northwestern Patagonia, Argentina
Autorzy:
DE LA FUENTE, MARCELO S.
MANIEL, IGNACIO
JANNELLO, JUAN MARCOS
STERLI, JULIANA
GARRIDO, ALBERTO C.
GARCIA, RODOLFO A.
SALGADO, LEONARDO
CANUDO, JOSÉ I.
BOLATTI, RAÚL
Powiązania:
https://bibliotekanauki.pl/articles/945623.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
testudines
pleurodira
post-cranial morphology
paleohistology
cretaceous
argentina
río negro
Opis:
Rionegrochelys caldieroi de la Fuente, Maniel, and Jannello gen. et sp. nov. is a Late Cretaceous turtle from Rio Negro Province, Argentina. The holotype and the referred specimens of this new species show an unusual shell morphology and microanatomy. The proportion between the carapace and plastron and the peculiar morphology of the shell such as the heart shaped carapace, a very deep nuchal notch, peripheral bones 2–11 with strongly gutter, the first vertebral scute twice as wide as long and subrectangular in shape, the posterior margin of vertebral scute 5 is three lobe shaped, and the unexpected osteohistology characterized by a massive structure, with higher compactness (80.6%) than other chelids, suggests beyond doubt that this turtle may be considered a new taxon. A semi-aquatic habitat with tendency towards terrestrial environments is inferred for Rionegrochelys caldieroi similar to that of the extant pelomedusid Pelomedusa subrufa among the extant pleurodires. Rionegrochelys caldieroi is recovered as a stem chelid. This new species seems to be closely related to Bonapartemys bajobarrealis and the clade formed by Lomalatachelys neuquina plus Mendozachelys wichmanni.
Źródło:
Acta Palaeontologica Polonica; 2017, 62, 3; 585-601
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth dynamics and body size evolution of South American long-necked chelid turtles: A bone histology approach
Autorzy:
Pereyra, M.E.
Bona, P.
Cerda, I.A.
Jannello, J.M.
De La Fuente, M.S.
Desantolo, B.
Powiązania:
https://bibliotekanauki.pl/articles/2082231.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Testudines
Chelidae
growth rate
body size
paleohistology
ontogeny
Paleocene
Argentina
Opis:
Among turtles, cases of “gigantism” occur mostly in pleurodiran Pelomedusoides and cryptodirans, but are infrequent among pleurodiran chelids, which are mostly small-medium sized turtles. Yaminuechelys spp. are extinct South American long-necked chelids (from the Late Cretaceous–early Paleocene of Patagonia, Argentina) with caparaces almost three times larger than their extant sister taxon, Hydromedusa tectifera. Since evolutionary changes in size can be analyzed based on growth dynamics, we studied growth strategies from an osteohistological point of view. We sampled both extinct (Yaminuechelys maior) and extant (H. tectifera) species, in order to test hypotheses related to the mechanisms involved in the macroevolution of size within this clade. For this purpose, thin sections of long bone (humerus and femur) shafts of specimens of different ontogenetic stages for these species were prepared. The osteohistological study reveals a similar growth dynamic in both taxa, with a poorly vascularized cortex dominated by parallel- fibered bone and interrupted by lines of arrested growth (LAGs). The huge body size of Y. maior appears to be a consequence of the prolongation of the growth phase, suggesting that it had a longer lifespan than H. tectifera, allowing to reach greater sizes. In this way, and assuming that there is no displacement at the beginning of development (e.g., a delay in the earliest stages of growth) in H. tectifera, the acquisition of a large size in Yaminuechelys would be explained by hypomorphosis of the former or hypermorphosis of the latter, depending on the reconstruction of the ancestral condition of this clade.
Źródło:
Acta Palaeontologica Polonica; 2020, 65, 3; 535-545
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First known gigantic sea turtle from the Maastrichtian deposits in Egypt
Autorzy:
Abu El-Kheir, G.A.-M
Abdelgawad, M.K.
Kassab, W.G.
Powiązania:
https://bibliotekanauki.pl/articles/2082330.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Testudines
Panchelonioidea
Cheloniidae
humerus
Cretaceous
Maastrichtian
Dakhla
Abu Minqar
Egypt
Opis:
The Maastrichtian deposits in Egypt and generally in Africa contain very few records of chelonioids. This scarcity hinders understanding the evolution and extinction of African chelonioids during this age. The Dakhla Basin in Egypt presents excellent Maastrichtian outcrops that consist of highly fossiliferous, calcareous siltstone and sandstone layers rich in ammonites, bivalves (Exogyra overwagi, Pycnodonta vesicularis, pectinids), gastropods, echinoids, corals, fossilized fruits of mangrove plants (Nypa) and vertebrate remains. The well-preserved humerus of giant turtle and other vertebrate remains have been discovered in the early late Maastrichtian Ammonite Hill Member of the Dakhla Formation in the Abu Minqar area, Southern Western Desert, Egypt. The Ammonite Hill Member was deposited in very shallow coastal, inner neritic to littoral environments. The well-preserved giant humerus represents the first record of gigantic Mesozoic chelonioids in Africa and the second record of chelonioids in the Maastrichtian deposits in Egypt. The present specimen contributes to fill the missing gaps in the history of Egyptian turtles from the Cretaceous through the Cenozoic.
Źródło:
Acta Palaeontologica Polonica; 2021, 66, 2; 349-355
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-12 z 12

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies