scholarly journals Pentadactyl manus of the Metoposaurus krasiejowensis from the Late Triassic of Poland, the first record of pentadactyly among Temnospondyli

2020 ◽  
Vol 237 (6) ◽  
pp. 1151-1161
Author(s):  
Dorota Konietzko‐Meier ◽  
Elżbieta M. Teschner ◽  
Adam Bodzioch ◽  
P. Martin Sander
Keyword(s):  
First Record ◽  
Late Triassic ◽  
Metoposaurus Krasiejowensis

scholarly journals The first occurrence of the enigmatic archosaur Crosbysaurus (Heckert 2004) from the Chinle Formation of Southern Utah

2014 ◽  
Author(s):  
Robert J Gay ◽  
Isabella St. Aude
Keyword(s):  
New Mexico ◽  
Close Association ◽  
First Record ◽  
Geographic Range ◽  
Type Locality ◽  
Late Triassic ◽  
Southern Area ◽  
Chinle Formation ◽  
First Occurrence ◽  
Unique Compound

Originally identified as an ornithisichian dinosaur, Crosbysaurus has been found in New Mexico, Arizona, and the type locality in Texas. The genus has been reassessed by other workers in light of revelations about the postcrania of another putative Triassic ornithischian, Revueltosaurus. The understanding of Triassic dental faunas has become more complicated by the extreme convergence between pseudosuchian archosaurus and ornithichian dinosaur dental morphologies. We report here on a new specimen of Crosbysaurus from the Petrified Forest Member of the Chinle Formation at Comb Ridge in southeastern Utah. This new specimen is assigned to Crosbysaurus on the basis of the unique compound posterior denticles, mediolateral width, and curvature. While this specimen, MNA V10666, does not help resolve the affinities of Crosbysaurus it does represent an approximately 250 kilometer extension of the geographic range of this taxon. This is the first record of this taxon in Utah and as such it represents the northernmost known record of Crosbysaurus. This indicates that Crosbysaurus was not limited to the southern area of Chinle/Dockum deposition but instead was widespread across the paleoriver systems of the Late Triassic in western Pangea. The specimen we report on here was found in close association with a typical Late Triassic Chinle fauna, including phytosaurs, metoposaurs, and dinosauromorphs.

scholarly journals First record of Mesozoic terrestrial vertebrates from Lithuania: phytosaurs (Diapsida: Archosauriformes) of probable Late Triassic age, with a review of phytosaur biogeography

2012 ◽  
Vol 150 (1) ◽  
pp. 110-122 ◽  
Author(s):  
STEPHEN L. BRUSATTE ◽  
RICHARD J. BUTLER ◽  
GRZEGORZ NIEDŹWIEDZKI ◽  
TOMASZ SULEJ ◽  
ROBERT BRONOWICZ ◽  
...  
Keyword(s):  
North America ◽  
Arid Regions ◽  
First Record ◽  
Upper Triassic ◽  
Late Triassic ◽  
Early Triassic ◽  
Baltic Region ◽  
Terrestrial Vertebrates ◽  
Terrestrial Vertebrate

AbstractFossils of Mesozoic terrestrial vertebrates from Lithuania and the wider East Baltic region of Europe have previously been unknown. We here report the first Mesozoic terrestrial vertebrate fossils from Lithuania: two premaxillary specimens and three teeth that belong to Phytosauria, a common clade of semiaquatic Triassic archosauriforms. These specimens represent an uncrested phytosaur, similar to several species within the generaPaleorhinus,Parasuchus,RutiodonandNicrosaurus. Because phytosaurs are currently only known from the Upper Triassic, their discovery in northwestern Lithuania (the Šaltiškiai clay-pit) suggests that at least part of the Triassic succession in this region is Late Triassic in age, and is not solely Early Triassic as has been previously considered. The new specimens are among the most northerly occurrences of phytosaurs in the Late Triassic, as Lithuania was approximately 7–10° further north than classic phytosaur-bearing localities in nearby Germany and Poland, and as much as 40° further north than the best-sampled phytosaur localities in North America. The far northerly occurrence of the Lithuanian fossils prompts a review of phytosaur biogeography and distribution, which suggests that these predators were widely distributed in the Triassic monsoonal belt but rarer in more arid regions.

scholarly journals Cranial bone histology ofMetoposaurus krasiejowensis(Amphibia, Temnospondyli) from the Late Triassic of Poland

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2685 ◽  
Author(s):  
Kamil Gruntmejer ◽  
Dorota Konietzko-Meier ◽  
Adam Bodzioch
Keyword(s):  
Bone Development ◽  
Cranial Bone ◽  
Late Triassic ◽  
Cranial Development ◽  
Biomechanical Loading ◽  
Calcified Cartilage ◽  
Single Bone ◽  
Occipital Condyles ◽  
Dermal Bones ◽  
Metoposaurus Krasiejowensis

In this study, 21 skull bones ofMetoposaurus krasiejowensisfrom the Late Triassic of Poland were investigated histologically. Dermal bones show a diploë structure, with an ornamented external surface. The ridges consist of mostly well vascularized parallel-fibered bone; the valleys are built of an avascular layer of lamellar bone. The thick middle region consists of cancellous bone, with varying porosity. The thin and less vascularized internal cortex consists of parallel-fibered bone. The numerous Sharpey’s fibers and ISF are present in all bones. The cyclicity of growth is manifested as an alternation of thick, avascular annuli and high vascularized zones as well as a sequence of resting lines. The detailed histological framework of dermal bones varies even within a single bone; this seems to be related to the local biomechanical loading of the particular part of the skull. The dynamic processes observed during the ornamentation creation indicate that the positions of the ridges and grooves change during growth and could be a specific adaptation to changing biomechanical conditions and stress distribution during bone development. In the supratemporal, the cementing lines show that the remodeling process could be involved in the creations of sculpture. The common occurrence of ISF suggests that metaplastic ossification plays an important role during cranial development. Endochondral bones preserved the numerous remains of calcified cartilage. This indicates that ossification follows a pattern known for stereospondyl intercentra, with relatively slow ossification of the trabecular part and late development of the periosteal cortex. The large accumulation of Sharpey’s fibers in the occipital condyles indicates the presence of strong muscles and ligaments connecting the skull to the vertebral column.

scholarly journals First haramiyid (Mammalia, Allotheria) from the Mesozoic of Gondwana

Fossil Record ◽  
1999 ◽  
Vol 2 (1) ◽  
pp. 159-170 ◽  
Author(s):  
W.-D. Heinrich
Keyword(s):  
East Africa ◽  
Food Processing ◽  
First Record ◽  
Upper Jurassic ◽  
Early Jurassic ◽  
Late Triassic ◽  
Central Basin ◽  
New Taxon ◽  
Tooth Crown ◽  
Cusp Height

Abstract. A haramiyid tooth is described from the Upper Jurassic of Tendaguru in southwestern Tanzania, East Africa. The specimen, identified tentatively as a lower posterior premolar, is made the holotype of a new taxon, Staffia aenigmatica gen. et sp. nov. which is placed in the Haramiyida. Staffia gen. nov. shares several features with Thomasia from the Late Triassic to Early Jurassic of Europe, notably the arrangement of cusps in two parallel longitudinal rows bordering a central basin, cusp height which progressively decreases in both rows posteriorly, the different height of the rows, the U-shaped posterior rim, and the smooth enamel surface. The main difference between these taxa is the presence of well-developed synclines with rounded floors in Staffia gen. nov., especially that of the principal syncline LS1. Resemblances in the basic tooth crown pattern indicate that occlusion and chewing might have been similar in both genera, but the synclines in Staffia gen. nov. suggest some subtle differences in food processing. Staffia aenigmatica gen. et sp. nov. is the first record of a haramiyid from Gondwana, and also the youngest stratigraphic occurrence for this allotherian group so far. Ein unterer Backenzahn aus den oberjurassischen Tendaguru-Schichten von Tansania in Ostafrika wird als Staffia aenigmatica gen. et sp. nov. beschrieben und zu den Haramiyida gestellt. Bei dem Fund handelt es sich wahrscheinlich um einen hinteren unteren Prämolaren. Staffia gen. nov. weist zahlreiche Merkmale auf, die bei der spät-triassischen bis früh-jurassischen Gattung Thomasia auftreten. Dazu zählen z. B. die Anordnung der Höcker in zwei unterschiedlich hohen Längsreihen, die in beiden Reihen von vorn nach hinten abnehmende Höckerhöhe, der U-förmige Hinterrand und die glatte Schmelzoberfläche. Die Synklinalen zwischen den Zahnhöckern von Staffia gen. nov. stellen ein neuerworbenes Merkmal dar. Die weitgehenden Übereinstimmungen im Grundaufbau der Zahnkronen beider Gattungen lassen darauf schließen, daß die Kieferbewegung und der Kauvorgang ähnlich waren, doch deuten die Synclinalen bei Staffia gen. nov. auf eine differenziertere Aufbereitung der Nahrung hin. Staffia aenigmatica gen. et sp. nov. ist der erste Nachweis eines Haramiyiden auf dem Gondwana-Kontinent und zugleich der bisher erdgeschichtlich jüngste Beleg für diese Säugetiergruppe. doi:10.1002/mmng.1999.4860020112

scholarly journals New species of osmundaceous fertile leaves from the upper Triassic of Argentina

2018 ◽  
Vol 58 (2) ◽  
pp. 107-119 ◽  
Author(s):  
Eliana P. Coturel ◽  
Josefina Bodnar ◽  
Eduardo M. Morel ◽  
Daniel G. Ganuza ◽  
Ana J. Sagasti ◽  
...  
Keyword(s):  
New Species ◽  
First Record ◽  
Late Triassic ◽  
Apical Region ◽  
New Taxon ◽  
Potrerillos Formation ◽  
Formed Part ◽  
Entire Margin ◽  
Early Late ◽  
A New Species

AbstractA new species of Osmundopsis Harris is described based on several impression-compression fossils from the upper section of the Potrerillos Formation (Uspallata Group) at Cerro Cacheuta Hill, Mendoza Province, Argentina. Osmundopsis zunigai sp. nov. is characterized by having fertile pinnae with a slender striate rachis, bearing widely separate, opposite to subopposite short falcate pinnules with an entire margin, rounded apex, and a partially reduced lamina. The pinnules bear sporangia loosely disposed in clusters of four or five on the abaxial side. The sporangia are wedge- to heart-shaped, shortly stalked, with cells of the apical region thickened, and have a vertical dehiscence slit. The spores are trilete and laevigate. This is the first record of Osmundopsis in the Triassic of Argentina. The mutual occurrence or co-preservation of Osmundopsis zunigai sp. nov. with sterile fronds of Cladophlebis kurtzi suggests the possibility that these species formed part of a dimorphic bipinnate frond. The diversity and geographic extent of fertile leaves of the Osmunda lineage in the early Late Triassic, with records in South Africa and Antarctica and now with this new taxon, support the idea of a moist mesothermal climatic belt in southern Gondwana.

scholarly journals First record of a basal mammaliamorph from the early Late Triassic Ischigualasto Formation of Argentina

PLoS ONE ◽  
2019 ◽  
Vol 14 (8) ◽  
pp. e0218791 ◽  
Author(s):  
Rachel V. S. Wallace ◽  
Ricardo Martínez ◽  
Timothy Rowe
Keyword(s):  
First Record ◽  
Late Triassic ◽  
Early Late
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