Przegl¹d Geologiczny, 48, 226-235 (2000)
Accumulation of skeletons of large Triassic tetrapods in the Opole Silesia

Dzik, J.,Sulej, T., Kaim, A. & NiedŸwiedzki, R.

Abstract. A new Paleorhinus fauna has been discovered in a grey claystone corresponding to the subsurface Drawno beds exposed in a cement plant claypit at Krasiejów near Opole in southern Poland. The fossils assemblage of very well preserved skeletons and isolated skulls and bones is dominated with labirynthodonts Metoposaurus diagnosticus, the phytosaur Paleorhinus sp. being the second in number. Species undeterminable etosaurs are represented by scuta and fragmentary bones. One sacral bones most probably representing an early dinosaur related to Staurikosaurus or Chindesaurus and two incomplete maxilla with teeth showing serration parallel to the cusp have been found. Rare dipnoans Ceratodus, undetermined fish scales and teeth, numerous unionid bivalves, very abundant characean gyrogonites, and ostracods are also represented. The Krasiejów Paleorhinus species is relatively short-snouted and may represent an earlier stage in the evolution of the lineage than the populations from Blasensandstein in Franconia and other known Paleorhinus faunas. This is consistent with the presence of Metoposaurus diagnosticus, the species originally described from the Schilfsandstein, located much below the Blasensandstein. An equivalent of Schilfsandstein is known in boreholes drilled nearby the locality and the fossil horizon is about 80 m above its top, and about 20 m above the last occurrence of gypsum in the section. Lehrberg Schichten in Germany seem thus to be its lateral equivalents, both presumably representing the final event in the Middle to Late Carnian eustatic cycle. The Paleorhinus fauna was apparently persistent in the area, as an incomplete skeleton has been found about 8 m below the most fossiliferous horizon, in a calcareous intercalation within red clays comparable with the German Rote Wand.