First report of aboral cups of the crinoid family Parahexacrinidae from the Middle and Upper Devonian of the Eifel (Germany) and the Holy Cross Mountains (Poland)

摘要

The rare Palaeozoic crinoid family Parahexacrinidae is reported here for the first time from the Lower Givetian of the Eifel Synclines (Rhenish Massif), expanding the geographic range to Germany. Shevchenkocrinus looghiensis gen. et sp. nov. is described based on isolated ossicles and two aboral cups from the Gerolstein and Hillesheim Eifel synclines and assigned to the family Parahexacrinidae. Furthermore, "Hexacrinites sp." sensu Guchowski (1993), from the Upper Frasnian of the Holy Cross Mountains (Poland), is transferred to the family Parahexacrinidae and classified as Parahexacrinitidae sp. I. comb. nov. Numerous parahexacrinitid species were erected based on the description of isolated columnals. New material from the Eifel proved that several of these species are not distinguishable from other crinoid groups, which is demonstrated for "Parahexacrinus ellipticus" and Melocrinites pyramidalis.