Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 74. (Budapest 1982)

Szabó, J.: Lower and Middle Jurassic Gastropods from the Bakony Mountains (Hungary). Part IV.: Neritacea, Craspedostomatacea, Amberleyacea (Archaeogastropoda)

Amberleya (Eucyclus) aff. carpathica UHLIG, 1878 (Plate II: fig. 14) aff. 1878: Amberleya carpathica UHLIG, p. 652, pl. XVII, fig. 1. Material: A fragmentary inner mould specimen with preserved shell portions and a shelly whorl-fragment. Shape : Dextral, high littoriniform with very thin, fragile shell. Whorl-surface without angulation, periphery carinate. Ornament : Longitudinal and transversal threads forming a retiform sculpture with small tubercles at the crossing points. At the periphery, one of the spiral threads is strengthened as carina and it bears periodically repeated small spines. Distribution : Bakony Mts., Somhegy: condensed Subfurcatum to Garantiana Zone. Remarks : Amberleya carpathica UHL. is the most similar species to the form from the Bakony Mts. by its shape and fine ornament, but the latter possess a thorny carina, only. Certainly it is representing a new species but the bad state of preservation does not allow a good diagnosis. Genus RISELLOIDEA COSSMANN, 1909 Riselloidea multistriata (BÖCKH 1874) (Plate III: figs. 3-6) 1874: Turbo multistriatus BÖCKH p. 110, pl. VI, fig. 5. Measurements: H HL HA D W A Plate III: figs. 3-6 13.5 8.5 16 9 Material : Sixteen inner moulds, mainly in bad state of preservation, but some of them with shell fragments. Shape : Dextral, turbiniform species of average size. The surface of the whorls is convex, the periphery is carinate. The peristome is prosocline with a somewhat thickened columellar lip separated from the convex base by a pseudoumbilicus. The aperture is rounded, but there are angulations at the foot of columella and at the suture. Ornament : Spiral carinae are present on the whorls and are on the base. The strongest three of these are situated at the periphery and immediately beside it. The lowermost one of these is just overlapped by the suture of the following whorl. All of the other carinae are similar in strength. They are separated by narrower, equal interspaces on the base. The transversal ornament consists of fine collabral cords, which are denser than the longitudinal elements. Usually they run from suture to suture (or to inner lip), but sometimes a few of the cords do not reach the upper suture, but disappear near to it. In such cases, short riblets appear at the suture beside the earlier ones. The ends of the riblets and the related cords do not meet. Nodulae or tubercles are sitting at the crossing points. The growth-lines are strongly prosocline, and somewhat opisthocyrt on the base. Distribution : Bakony Mts., Sümeg: ? Upper Sinemurian; Szentgál : Raricostatum and Ibex Zone ; Kisnyerges-árok : Upper Sinemurian- Lower Pliensbachian ; Közöskúti-árok : Ibex Zone ; Kericser: beds with mixed Obtusum to Ibex Zone faunas and Davoei Zone; ? Káváshegy; ? Davoei Zone; Büdöskút-Középhát: Stokesi and Margaritatus Zone; Bocskorhegy: Davoei Zone. Remarks : Riselloidea multistriata (BÖCKH) was the only species described befcre the present series from the Bakony Mts. Jurassic. The holotype deposited in the Museum of Hungarian Geological Institute is just like the available specimens in shape and ornament, but the depiction given by BÖCKH is somewhat incorrect, since the peripherial carinae follow each other with greater interspaces in reality than on the figure.