A new Triassic (Ladinian) association with a large temnospondyl, sauropterygians, a gigantic prolacertiform, and an archosauriform in Miedary (Southern Poland) [poster]

Abstract

A new Triassic vertebrate assemblage in Miedary, southern Poland was recently discovered. The sediments represent the lowermost Keuper (Miedary beds) of Middle Triassic (late Ladinian) age. Collected fossils comprises to an important component of the total vertebrate assemblage from the Triassic of Poland. The newly discovered material includes a large temnospondyl, sauropterygians, a gigantic prolacertiform, an archosauriform and a microfauna that includes numerous actinopterygian scales, skeletal elements and teeth. We collected the analyzed vertebrate fossils from three lithologically different types of deposits. The first assemblage occurs in yellowish dolomites, where poorly preserved invertebrate macrofossils (brachiopods, bivalves, gastropods) and microfossils (ostracods, foraminifera) were also found. It contains nothosaurid vertebrae and long bones, and numerous fish microremains. The second occurs in the greyyellowish, sometimes greenish or reddish claystone and mudstone. We found isolated or partially articulated bones of temnospondyls, elongated vertebrae and long bones of prolacertiforms, and partially preserved long bones and teeth of archosauriforms from these deposits. We also found poorly preserved vertebrate coprolites and charophyte gyrogonites in the same clayish deposits. In sandstones we found intercalations of partially preserved and rich but highly disarticulated fish fossils (mainly scales) and poorly preserved plant remains. This new association from the marginal-marine strata shows some similarities to vertebrate assemblages known from the lower Keuper of Germany and also the Ladinian of southern Europe.