Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 26. 2008. (Budapest, 2008)

others ones belong to a new species {Discohelix pseudomelia n. sp., see below). Both species differ from Discohelix orbis in their shape, the measurements and the ornaments, too. Their adult size is much smaller, and the fully-grown stage is indicated by characteristic last whorl morphology. However, the close relation to Discohelix orbis needs careful observation of the morphological characters in young specimens (see details below). The specimens, figured by M. GEMMELLARO (1911) as "Discohelix orbis var. omatd" represent a new species (neither orbis, nor ornata; pers. obs.), however, the not figured part of his collection contains also true Discohelix orbis. Figure 2 — Discohelix orbis (REUSS, 1852). — 8 a-e: copied original figures from STOLICZKA (1861) Tafel III.; c: this type of corrugation has not been found in D. orbis, it was probably drawn from the specimen, introduced in Figure 3: A-D and M—N (below); A-F: neotype, one of the possible original specimens to STOLICZKA's figures in Tafel III, Fig. 8 a, b, d, e; A = spiral view, xl, B = aperture view, xl, C = umbilical view, xl, D = back view, xl, E = ornament on the umbilical side (details of C; ornament of spire is symmetrical to that), x2, F = details of ornament on the outer side, magnified from D, x2; G—H: spire side of another shell (paraneotype) from the collection of STOLICZKA (1861) figured specimens, G = xl, H = x2. Distribution — Discohelix orbis (REUSS, 1852) is one of the most widespread and most frequent element in the latest Sinemurian to latest Pliensbachian gastropod assemblages in the Mediterranean Faunal Province of the Tethyan Realm. D. orbis commonly occurs in association with Eucyclus alpinus STOLICZKA, 1861 in the Pliensbachian. They are the gastropods, which have inhabited also the deepest water biotopes; they have been found also in lots of "Adnet" (or "Rosso Ammonitico") Limestone localities. Northern Calcareous Alps, (Austria, Germany), Sinemurian (from Oxynotum Zone) to Upper Pliensbachian; Eastern and Western Sicily, Central Apennines (Italy), Pliensbachian; Southern Alps, Pliensbachian; Bakony and Gerecse Mts (Hungary), Upper Sinemurian to Upper Pliensbachian; ? Crimea, Caucasus, Pliensbachian. The earliest occurrence of the species is in the Oxynotum Zone (Sinemurian) and the latest finds are known from the Stokesi Zone (uppermost Pliensbachian). Discohelix ornata (HÖRNES, 1853) (Figure 3: E—L) 1853: Euomphalus ornatus HÖRNES — HÖRNES in HAUER, p. 760. pars 1861: Discohelix orbis REUSS — STOLICZKA, p. 182, pi. 3, fig. 9-10. non (v) 1911: Discohelix orbis REUSS var. ornata Homes — GEMMELLARO, M., p. 218, pi. 10, figs 9-12. non 1979: Discohelix cf. ornata (HÖRNES, 1853) — SZABÓ, p. 21, pl. 1, fig. 4. L e c t o t y p e — GBa 2008/69/32/2/1.