Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 70. (Budapest 1978)

Vörös, A.: Viallithrys gen. n. (Terebratulida, Brachiopoda) from the Mediterranean Lower Jurassic

crenulated, tongue which fits well under the transverse band of the loop. It is important to note that this structure is only loosely attached both to the brachidium and to the brachial valve; furthermore, it shows a rather irregular, sometimes asymmetrical development. Nevertheless, it is a constant and characteristic feature in the specimens of V. gozzanensis as can be observed in the figures 22 and 23 by SACCHI VIALLI & CANTALUPPI (1967) as well. The new term "brachidium support" is suggested here for this structure since it is not homologous with the similar skeletal elements of some other articulates (e. g. the "outer plates" of the Gypidulidae; the "crural plates" of the Centronellidae and some Dielasmatidae, etc.). The dorsal adductor muscle scars are narrow, short and subparallel as seen on the surface of internal moulds (Fig. 5). Remarks: Parona (1880) described "7". Gozzanensis" and "7\ Sismondai" as distinct species but later he (PARONA 1885) considered the latter only as a variant of gozzanensis. T. engeli HAAS has been included into the synonymy by SCHLOSSER (BÖSE & SCHLOSSER 1900) and this seems reasonable on the basis of the figures given by HAAS (1884). Recently, SACCHI VIALLI & CANTALUPPI (1967) gave good illustration of this species including two series of transverse sections but left open the question of generic assignment. The anterior parts of the brachidium support are slightly different from those figured in the present paper; this probably reflects varation during ontogeny since the specimens of SACCHI VIALLI & CANTALUPPI are much larger. V, gozzanensis has some external similarity to Rhapidothyris arciferens TULUWEIT, 1965, and especially to Rhapidothyrisl reversa (AGER, 1956), however, their internal characters are very different from those of V. gozzanensis in accordance with the different generic position. The brachidium support appears in several terebratulid species in the Mediterranean Jurassic but their other internal and external characters make them easily separable even at generic level. Distribution: V. gozzanensis has a characteristically Alpine (Mediterranean) distribution. It has been described first from the Pliensbachian of Gozzano (Piemonte) and later from several other localities of the Southern Alps and the Northern Limestone Alps, from the same stage. — The Hungarian specimens came from the northern part of the Bakony Mts. Localities: Kericser (Ibex, Davoei and Stokesi Zones); Kávástető (Davoei Zone); Fenyveskút (probably Margaritatus Zone); Eplény, manganese-ore mine (probably Margarita tus Zone). Fig. 5. Two specimens of Viallithyris gozzanensis (PARONA) showing the narrow, short and subparallel dorsal adductor muscle scars. Carixian (Ibex Zone); Kericser, near village Lókút, Bakony Mts., Hungary. x2. Hung. Geol. Inst., J. 9179 and J. 9180