Torleyiscutellum herwigorum n. gen., n. sp. (Trilobita) from the Upper Honsel Beds of the north-western Sauerland (Lower Givetian, Rhenohercynian Zone), with a contribution to scutelluid systematic

The Oege Beds (Upper Honsel Beds) of the geological mapsheets 4610 Hagen and 4611 Hohenlimburg, Remscheid-Altena Anticline, are intercalated between the mainly siliciclastic Lower Honsel Beds and the reefal Massenkalk. They belong to the Lower Givetian Upper hemiansatus Biozone. They bear reefal limestones, carbonatic siltstones and claystones yielding a largely little known fauna of the neritic biofacies including anthozoans, brachiopods, bivalves, bryozoans, chaetetids, crinoids, gastropods, stromatoporids, and trilobites. The trilobites are represented by one species of the subfamily Scutelluinae and two species of the subfamily Dechenellinae. Torleyiscutellum herwigorum n. gen., n. sp. is a representative of a group of scutelluids formerly assigned to Scutellum costatum. In Brontes flabellifer, type species of Goldius, the cranidial posterior border furrow is in contact with the ledge accompanying postpalpebral parts of the facial suture (primitive condition), whereas in Torleyiscutellum torleyi the two units are separated by a branch of the posterior fixigena protruding abaxially (derived condition). Scutellum costatum, type species of Scutellum, is restricted to its neo-type. Finds of Dechenella burmeisteri in the north-western Sauerland suggest for the base of the Oege Beds a position close to the Rodert Formation-Kerpen Formation boundary of the Standard Division of the Eifel Synclines. This is a suggestion for a new biostratigraphic concept on a macrofaunal base.