Article: Spinatrypa and Spinatrypina (Devonian Brachiopoda)
The Eifelian-Givetian (Middle Devonian) sediments of Germany contain a near-continuous suite of brachiopods belonging to the genera Spinatrypa Stainbrook 1951 and Spinatrypina Rzhonsnitskaya 1964. These two allopatric atrypid genera occupy different, mutually exclusive environments: the first is dominant in a brachiopod biotope, and the other is invariably associated with small thamnoporid or disphyllid corals. Several new taxa of limited vertical distribution are briefly described. These are Spinatrypa variaspina, S. aspera meridiana, S. globulina, S. curvirostra, S. orthoclina, and Spinatrypina demissa, S. fabaca, S. girzenensis. Small changes in critical correlations of the Eifel region are suggested. In Germany, and probably elsewhere in Europe, the Spinatrypa-Spinatrypina atrypids of Givetian age predominantly replaced the Atrypa group common to Eifelian rocks, a feature possibly of major significance in marking the Eifelian-Givetian boundary.