Vertebrate remains from the Lower Muschelkalk of Raciborowice Górne (North-Sudetic Basin, SW Poland)

Abstract

Vertebrate remains, mostly fish teeth and scales, are described from the Lower Muschelkalk of Raciborowice Górne, North-Sudetic Basin, SW Poland. The assemblage occurs in dark grey organodetrital limestone of unit C. Vertebrate remains, represented mainly by vertebrate bones and coprolites, are also known from unit B. Five taxa of chondrichthyan teeth -- Acrodus lateralis, Acrodus cf. lateralis, Acrodus sp., Palaeobates angustissimus, Palaeobates sp. and, for the first time from this region, two taxa of osteichthyan remains -teeth of Birgeria sp., scales from Gyrolepis sp. as well as scales from unclassified actinopterygians and enigmatic bones (fishes?) are described from the Lower Muschelkalk at Raciborowice Górne. Reptile teeth representing the Nothosauridae or Cymatosauridae have been found for the first time at this locality. They were discovered in the Bone Bed of unit C, that had previously only yielded fish teeth. The material collected has allowed reconstruction of the vertebrate assemblage of the Lower Muschelkalk of the North-Sudetic Basin. It has also helped to constrain reconstructions of the palaeoenvironment, suggesting that it represented a deepening lagoon. The assemblage has been correlated with age-equivalents from other regions of Europe, the faunas from the Holy Cross Mts. (Central Poland) being the closest analogy. The evidence indicates that, during the deposition of units B and C that, contain the vertebrate remains, connection with the Tethys Ocean was through the Silesian-Moravian and East Carpathian marine gateways.