A new species of inarticulate brachiopods, Discinisca zapfei spn, from the Upper Triassic Zlambach Formation , and a discussion of other Triassic disciniscans
Radwanski, A.; Summesberger, H.
Annalen des Naturhistorischen Museums in Wien A Mineralogie Petrologie Geologie Palaeontologie Archaeozoologie Anthropologie Praehistorie 102A: 109-129
A new species of inarticulate brachiopods, Discinisca zapfei sp.n., is established for specimens collected by the late Professor Helmuth ZAPFE from the Zlambach Formation (Upper Triassic, Norian to Rhaetian) of the Northern Calcareous Alps (Austria). The collection, although small, offers a good insight into the morphology of both the dorsal and the brachial valve of the shells, as well as into their mode of growth in clusters. The primary shell coloration is preserved, probably due to a rapid burial (? tempestite) of the clustered brachiopods in the living stage. A review and/or re-examination of other Triassic disciniscan brachiopods indicates that the newly established species, Discinisca zapfei sp.n., is closer to certain Paleogene-Neogene and/or present-day species than to any of the earlier described Triassic forms. The environmental requirements of the newly established species were characterized by shallow marine, tropical and/or sub-tropical conditions, which coincides with the formerly known life conditions of the Alpine Late Triassic (Norian and/or Rhaetian) communities, whose development was controlled by a general bioevolutionary turnover at the Triassic decline.