Jean-Sébastien Steyer

New actinopterygians from the Permian of the Brive Basin, and the ichthyofaunas of the French Massif Central

Abstract

A new actinopterygian fauna from the Permian of the Brive Basin (Corrèze, Massif Central, France) is described in detail. It is represented by a new pygopterid taxon, Briveichthys chantepieorum gen. et sp. nov., erected and described here on the basis of several well-preserved specimens showing peculiar characters in the bones of the skull roof, parasphenoid, bones of the cheek and opercular apparatus. Other specimens from this new fauna are also described; they are referred to Progyrolepis heyleri Poplin, 1999, also known in the Bourbon-l’Archambault Basin, and Aeduella cf. blainvillei, which is relatively common in the Permian of France. These discoveries show the importance of the Brive Basin which was previously considered as a rather barren basin in term of palaeontology. This new fauna from Brive is compared with the other Permian ichthyofaunas from France: it is less rich in terms of specimen numbers than the faunas of Bourbon-l’Archambault and Autun, but it is more diversified in terms of number of taxa than the faunas of Lodève and L’Argentière (Ardêche). These actinopterygians, together with other aquatic vertebrates (e.g., acanthodians, sharks etc.), were widespread and diversified in the Hercynian Mountain Chain during the Permian. They indicate that the French basins were connected in time and space. The wide distribution of these aquatic taxa may have been favoured by numerous hydric systems (lakes, rivers etc.) which were well developed under the tropical climate.

Key words

Actinopterygii, anatomy, Permian, Brive Basin, French Massif Central

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A new stereospondylomorph, Korkonterpeton kalnense gen. et sp. nov., from lower Permian of the Czech Krkonoše Piedmont Basin and a redescription of Intasuchus silvicola from the lower Permian of Russia (Temnospondyli, Amphibia)

Abstract

A new temnospondyl, Korkonterpeton kalnense gen. et sp. nov., is described on the basis of an almost complete specimen from the lover Permian Prosečné Formation of the Czech Krkonoše Piedmont Basin. The exceptional preservation of the holotype allows a detailed description of the cranial and postcranial characters: Korkonterpeton kalnense gen. et sp. nov. is characterized by the presence of vomerine fangs located anteriorly to the posterior choana, much longer than wide tabulars – as long as the supratemporals, a deeply concave posterior margin of the skull table, extraordinarily elongated exoccipitals, anteriorly widened pterygoids and a parasphenoid cultriform process swollen at its mid-length. In order to clarify the relationship between this new taxon and Intasuchus silvicola Konzhukova, 1956 from the lower Permian (late Kungurian) of the Russian Inta Basin, the latter is also redescribed here: Intasuchus silvicola exhibits a lacrimal entering the septomaxilla, a widened jugal, a posterolaterally widened interpterygoid vacuity, a subtemporal window elongated anteriorly up to the anterior orbital region, an elongated basipterygoid ramus which is as long as the orbit width, a vomer with a parachoanal tooth row, and an ectopterygoid of about the same length as the palatine. The description of Korkonterpeton kalnense gen. et sp. nov. and the revision of Intasuchus silvicola complete our knowledge on the origin and evolution of early stereospondylomorph temnospondyls during the lower Permian.

Key words

Korkonterpeton kalnense gen. et sp. nov., Krkonoše Piedmont Basin, Bohemian Massif, lower Permian, Intasuchus silvicola, anatomy, relationships

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