The cladid crinoid Gissocrinus Angelin from Wenlock Edge, Shropshire (Silurian)

摘要

Complete fossil crinoids are well known from the Much Wenlock Limestone Formation (Silurian, Wenlock, Homerian), but are only common in the Dudley area of the West Midlands. Elsewhere, Wenlock crinoids are preserved as disarticulated ossicles. For example, only about six nominal crinoids are known from the type area of the Much Wenlock Limestone Formation on Wenlock Edge. Herein, we document abundant remains of the cladid crinoid Gissocrinus spp. from near Much Wenlock, Shropshire, based on common brachial and rare radial ossicles. Brachials are mainly thin and quadrate with a U-shaped adoral groove. There are six nominal species of Gissocrinus in the Wenlock of the British Isles; probability suggests that this sample contains elements of more than one species.