Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 72. (Budapest 1980)

Szabó, J.: Lower and Middle Jurassic Gastropods from the Bakony Mountains (Hungary). Part II.: Pleurotomariacea and Fissurellacea (Archaeogastropoda)

On the other hand, the angulation of the whorl-surface, with the subjacent selenizone, is well-marked án the former species, and this also suggests clearly that it belongs into the genus Pleurotomaria. Distribution — Northern Alps: Hierlatz Limestone; Sicily, Galati: "Pygope aspasia zone"; Bakony Mts., Eplény: Domerian; Hamuháza: Davoei Zone. Family Trochotomidae Cox, 1960 Genus TROCHOTOMA EUDES-DESLONGCHAMPS, 1843 Trochotoma striatum HÖRNES, 1853 (Plate IV: fig. 5) 1853: Trochotoma striatum HÖRNES — HÖRNES, p. 762. 1861: Trochotoma striatum HÖRNES — STOLICZKA, p. 193, pi. 5, fig. 2. Measurements: H HL HA W D A Plate IV: fig. 5. — 38 25 30 54 76° Material — Two fragmentary specimens from the fissure-filling material of Eplény. The preserved parts are with shell and of good preservation. Shape — Dextral form with shell of a wide-based cone in shape. The spire is gradate, the whorl-surface is markedly convex, and the periphery is rounded-angular. The broad selenizone is situated somewhat above mid-whorl. The base is markedly convex, with funnel-shaped umbilicus. The peristome, on the basis of visible fragmentary portions, is elongated. The upper part of the outer lip is markedly prosocline, and the inner lip, in its part arching into the umbilicus, is slightly thickened. Ornament — The surface of the whorls, as well as the base, is ornamented with spiral cords. Every second spiral cords running on the selenizone or in the umbilical region, are weaker than the others. The transverse elements are the growth-lines and the riblets, the latter arise from the suture and fade out well before the selenizone. The density and the initial strength of these elements are similar to those of the spiral cords. The growth-lines are markedly proscline above the selenizone, somewhat opisthocline between the selenizone and the periphery, and opisthocyrt on the base, respectively. Remarks — Previous authors did not mention the presence and the place of the exhalant opening (trema), thus the most important basis for the generic arrangement is missing. Disregarding this fact, the visible other morphological characteristics do not preclude the unit of this species with the genus Trochotoma. Despite the fact that all the available specimens lack the trema, its probable position can be determined indirectly, through a shell-damage. The gowth (or "lengthening") of the shell stopped for a time of repair a damage near the suture. However, the carbonate secretion remained continuous. Thus, at the time of the make up for the broken shell-part, the shell became thickened on the base, between the periphery and the selenizone, up to the damaged part, resulting actually in a varix. The selenizone shows the corresponding thickening, and this marks the posterior end of the trema. It is situated in a coaxial projection with c. 60° behind the former peristome. This fact apparently proves the generic arrangement correct, because in other genera of the superfamily Pleurotomariacea the growing end of the selenizone rarely exceeds the 20 to 25° distance from the peristome. It is especially true for those forms with wide selenizone, just as in Trochotoma striatum. Distribution — Alps: Hierlatz Limestone; Bakony Mts., Eplény: Domerian. Superfamily Fissurellacea FLEMING, 1822 Family Fissurellidae FLEMING, 1822 Genus AUSTRIACOPSIS HABER, 1932 Subgenus AUSTRIACOPSIS HABER, 1932 Austriacopsis (Austriacopsis) austriaca (HÖRNES, 1853) (Plate IV: figs. 6-9.) 1853: Rimula austriaca — HÖRNES, p. 753. 1861: Rimula austriaca HÖRNES — STOLICZKA, p. 193, pi. 5, fig. 3. 1934: Austriacopsis (Austriacopsis) austriaca (HOERNES, 1853) — HABER, p. 254. 5 Természettudományi Múzeum Évkönyve 1980