Rineceras Hyatt, 1893

Korn, Dieter & Klug, Christian, 2023, Early Carboniferous coiled nautiloids from the Anti-Atlas (Morocco), European Journal of Taxonomy 885, pp. 156-194 : 160

Genus Rineceras Hyatt, 1893

Type species

Gyroceras propinquum de Koninck, 1880 ; subsequent designation by Foord (1900).

Diagnosis

Genus of the family Trigonoceratidae with usually discoidal subevolute to evolute conch; whorls detached or slightly in contact; whorl profile elliptical or rounded triangular with broad venter. Conch moderately to rapidly increasing in height with a high coiling rate (WER usually higher than 2.00). Ornament with coarse growth lines and coarse spiral ridges; coarse granulation at the crossing points of growth lines and spiral ridges. Septa without inflexions, rather deeply concave. Suture line with shallow external and lateral lobes. Siphuncle small with subcentral position (after Kummel 1964; Shimansky 1967; emended).

Included Early Carboniferous species

Early Carboniferous species of Rineceras are known from a number of regions such as:

North America ( Meek & Worthen 1860; Miller & Garner 1953): Nautilus (Discus) digonus Meek & Worthen, 1860 , Indiana; Rineceras ohioense Miller & Garner, 1953 , Ohio.

Northern and Central Europe ( Fleming 1828; de Koninck 1844, 1880; Holzapfel 1889; Schmidt 1951; Turner 1954): Nautilus Luidii Fleming, 1828 , Derbyshire; Gyroceras Meyerianum de Koninck, 1844 , Belgium; Gyroceras propinquum de Koninck, 1880 , Belgium; Nautilus rhenanus Holzapfel, 1889 , Rhenish Mountains; Triboloceras patteiskyi Schmidt, 1951 , Rhenish Mountains; Pararineceras balladoolense Turner, 1954 , Isle of Man.

North Africa ( Korn & Bockwinkel 2022; Korn et al. 2022): Rineceras multituberculatum Korn, Miao & Bockwinkel, 2022 , Algeria; Rineceras rectangulatum Korn, Miao & Bockwinkel, 2022 , Algeria; Rineceras tenerum Korn & Bockwinkel, 2022 , Algeria.

Western Russia, Urals and Kazakhstan ( Eichwald 1857; Kruglov 1933; Shimansky 1967): Nautilus canaliculatus von Eichwald, 1857 , South Urals; Nautilus carinatus von Eichwald, 1857 , Western Russia; Rhineceras alapaevskensis Kruglov, 1933 , Urals; Rineceras carinatiforme Shimansky, 1967 , Kazakhstan.

Remarks

For a discussion of the composition and limits of the genus, seeKorn et al. (2022) andKorn & Bockwinkel (2022).