Review of some Frasnian ahermatypic coral localities from Germany and description of a new genus Spinaxon (Anthozoa, Rugosa, Upper Devonian)

One of the greatest gaps in the present worldwide knowledge of Rugosa history are the unstudied ahermatypic coral faunas of Frasnian (and Upper Givetian) times, though they exist in many places. Most occurrences in Germany are briefly reviewed (Variscan Rhenish, Harz, Thuringian and Franconian Mountains; Baltoscandian shelf deposits in deep boreholes on the Baltic Sea island of Rügen). Intensive collecting in Thuringia presented rich Upper Frasnian samples from two localities (former Geipel quarry in the town of Schleiz, Vogelsberg-quarry near the village Tegau), dominated by Metriophyllum Milne-Edwards & Haime, 1850, Neaxon Kullmann, 1965, and the newly established genus Spinaxon (suborder Cyathaxoniina, family Petraiidae), with the monotypic type species Spinaxon potyi sp. nov. Cephalopod limestones yielded >100 specimens of this taxon; one specimen was found in the Montagne Noire (Frasnian Famennian boundary stratotype section Coumiac). The taxon descends from Neaxon Kullmann, 1965 or its nearest relative Petraia Münster, 1839; it is characterized by unique hypertrophic long trabicular spines on the margins of major septa within an aulos of circulotheca type.