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On a new stereospondylomorph temnospondyl from the Middle-Late Permian of Southern Brazil

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Strapasson A., Pinheiro F. L., Soares M. B.

Acta Palaeontologica Polonica

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2015

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tom 60

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nr 4

A new temnospondyl is described from the Middle-Upper Permian sequence of the Paraná Basin (Rio do Rasto Formation) in southern Brazil. The material consists of disarticulated cranial and postcranial elements, preserved in association. The cranial elements include part of the orbital region of the skull roof, the basicranium, a number of en-docranial elements, stapes and a right hemimandible. The postcranial elements include vertebrae, ribs, pectoral girdle elements, a right femur and a cluster of scales. The new species displays a rhinesuchid pattern, which is similar to the South African rhinesuchids from the Upper Permian Beaufort Group of the Karoo Basin, but differs from them by the presence of a robust and elongated epipterygoid with a blade-like anterior process in addition to elongated and deeper muscular pockets on the parasphenoid, which allow the assignment of this specimen to a new species. However, the phylogenetic analysis grouped the material described herein andAustralerpeton cosgriffi inside Stereospondylomorpha, in a transitional position between the Laurasian assemblages and South African temnospondyls. This result supports a connection between the Brazilian and Eastern European Permian fauna and provides important data for future biostratigraphic studies.

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The pustulated temnospondyl revisited - a plagiosternine plagiosaurid from the Lower Triassic of Brasil

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Dias-Da-Silva S., Milner A. R.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 3

561-563

A recent contribution published in this journal (Dias−daSilva and Ilha 2009) reported a dermal skull fragment indicating the presence of a putative plagiosauroid temnospondyl in the Lower Triassic Sanga do Cabral Formation of the Paraná Basin, Southern Brazil. The taxonomic assignation of this specimen was necessarily tentative as it was based on circumstantial evidence, specifically the presence of a dense pustular ornamentation over four partial dermal skull bones, consideration of the described taxa known to bear such ornamentation, and the stratigraphic and paleobiogeographic range of such taxa. Therefore, Diasda−Silva and Ilha (2009) could not be totally certain about the plagiosauroid affinities of the new specimen and ascribed it to ?Plagiosauridae. It was particularly difficult to make a precise osteological identification of the specimen and six alternative osteological interpretations were made in comparison to both Gerrothorax and Peltobatrachus (see Dias−da−Silva and Ilha 2009: fig. 2). In spite of the poor taxonomic resolution, the new specimen raised interesting questions regarding the presence of plagiosauroid stereospondyls in western Gondwana, as well as their evolutionary patterns, biostratigraphic and paleobiogeographic implications. After Dias−da−Silva and Ilha's (2009) contribution was published, new data from Damiani et al. (2009) raised the possibility of narrowing down the taxonomic identity of the plagiosauroid from Brazil. Accordingly, this brief report provides a more precise taxonomic assignation for this material.

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On the presence of a pustulated temnospondyl in the Lower Triassic of southern Brazil

100%

Dias-da-Silva S., Ramos Ilha A. L.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 4

The fossil record of temnospondyls in South America has been greatly expanded in the last 10 years, increasing their overall significance. They occur in Argentina, Brazil, and Uruguay, and range from the Guadalupian to the Late Triassic. The Early Triassic temnospondyl record in southern Brazil is mainly composed of fragmentary specimens, usually represented by dermal skull bones from the Sanga do Cabral Formation. Some of these fragments were tentatively referred to Lydekkerinidae and Rhytidosteidae based on their characteristic ridge−grooved “spider−web” pattern of ornamentation. In this contribution we report, for the first time, a temnospondyl skull fragment with pustulated sculpturing pattern, which is tentatively ascribed to Plagiosauridae. This new record could indicate the presence of a new temnospondyl taxon for the Lower Triassic of South America.

Ograniczanie wyników

3 Acta Palaeontologica Polonica

1 Dias-Da-Silva S.

1 Dias-da-Silva S.

1 Milner A. R.

1 Pinheiro F. L.

1 Ramos Ilha A. L.

1 Soares M. B.

1 Strapasson A.

1 2015

1 2010

1 2009

On a new stereospondylomorph temnospondyl from the Middle-Late Permian of Southern Brazil

The pustulated temnospondyl revisited - a plagiosternine plagiosaurid from the Lower Triassic of Brasil

On the presence of a pustulated temnospondyl in the Lower Triassic of southern Brazil