Middle Miocene (Badenian) brachiopods from the Roztocze Hills, south-eastern Poland

Abstract

The brachiopod assemblage from the Middle Miocene (Badenian) shallow water deposits of the Roztocze Hills (Lublin Upland, south-eastern Poland) comprises eight species belonging to six genera. Four of them, i.e. Ancistrocrania abnormis (DEFRANCE), Cryptopora sp. A, Cryptopora sp. B. and Platidia cf. anomioides (SCACCHI & PHILlPPI) are very rare, while the species Megathiris detruncata (GMELIN), Argyrotheca cuneata (RISSO), A. cordata (RISSO) and Megerlia truncata (LINNAEUS) are very abundant what allows the range of morphological variability of those species to be recognized. Three species: Ancistrocrania abnormis, Platidia cf. anomioides and Argyrotheca cuneata are reported for the first time from Poland. The brachiopod percentages in particular samples show considerable differences although the samples come from the shallow water deposits originating in similar conditions and during a narrow span of time. Thus, the brachiopod assemblage structure seems to be controlled not only by depth but by such factors as particular substrate and habitat availability as well. The brachiopod fauna from the Roztocze Hills displays the resemblance to the Miocene one from the Mediterranean region as well as to the Recent one living in the Mediterranean Sea.