Ephippioceras Hyatt 1884

Genus Ephippioceras Hyatt, 1884 Type species Nautilus ferratus Cox, 1858; original designation. Diagnosis Genus of the family Ephippioceratidae with pachyconic to globular, involute conch. The first whorl is about 10 mm in diameter; the conch is rapidly increasing in height with a high coiling rate (WER usually higher than 2.50). Whorls weakly embracing, with reniform profile. Shell surface smooth, sometimes with fine spiral lines. Septa bipartite by a median inflexion and two strongly concave lateral sides. Suture line with subtriangular external saddle, shallow lobes on flanks and umbilical wall and rounded internal saddle. The siphuncle has a position between the centre of the aperture and the venter (after Gordon 1965; Shimansky 1967). Included Early Carboniferous species North America (Cox 1858): Nautilus ferratus Cox, 1858, Kentucky. British Isles (Sowerby 1821; Ramsbottom & Moore 1961): Nautilus bilobatus Sowerby, 1821, Scotland; Ephippioceras spirale Ramsbottom & Moore, 1961, Ireland. North Africa (this paper): Ephippioceras pygops sp. nov.; Anti-Atlas. West Russia and Urals (Hyatt 1891; Fredericks 1915; Shimansky 1967): Ephippioceras Verneuili Hyatt, 1891, South Urals; Ephippioceras mosquense Fredericks, 1915, Moscow Basin; Ephippioceras sphaericum Shimansky, 1967, South Urals. Remarks Ephippioceras is a genus of which several of the species are known from only a few specimens; furthermore, the very different sizes of the described specimens make a comparison difficult. Another problem is the often fragmentary preservation of the material.Published as part of Korn, Dieter & Klug, Christian, 2023, Early Carboniferous coiled nautiloids from the Anti-Atlas (Morocco), pp. 156-194 in European Journal of Taxonomy 885 on pages 181-182, DOI: 10.5852/ejt.2023.885.2199, http://zenodo.org/record/822241