Vörös A. szerk.: Fragmenta Mineralogica Et Palaentologica 16. 1993. (Budapest, 1993)
Phvlum BRACHIOPODA Class ÁRTICULATA Huxlev, 1869 Order RHYNCHONELL1DA Kuhn. 1949 Superfamily RHYNCHONELLACEA Gray, 1848 Family Wellerellidae Likharev, 1956 Subfamily Cirpinae Ager, 1965 Genus Calcirhynchia Buckman. 1918 Calcirhynchia ?plicatissima (Quenstedt, 1852) (Plate I: Fig. 1; Text-fig. 2) 1992 Calcirhynchia ? plicatissima Quenstedt - Dulai: p. 44. pl. 1, fig. 3. (cum. syn.) Material: Cuha-völgy (2), Lókúti-domb (3) and Tűzköves-hegy (1). Dimensions (mm): Specimen M.93.4. (Text-fig. 2) length: 11.1. width: 12.2. thickness: 7.1. Description - External characters: Small shell, subtriangular in outline. The sides of triangle are straight, the base ff^f'H ür ^ win S of triangle is convex. The angle between the lateral margins 0t tea • m ' is about ^ lu5 °- The two corners are rounded at the anterior T^zköves-heev margin. The width is a little larger than the length, while the thickness is three-quarter of the length. Biconvex form, the convexity of the pedicle and the brachial valves are equal. The maximum width is at the anterior third, while the maximum convexity is at the half of the length. The beak is small and suberect. There are no beak ridges and planareas. The lateral commissures are straight, the anterior commissure is uniplicate. The plica is wide, slightly arched and low. All the surface of shell is cos ta te, 16-18 costae run straight on each valve to the anterior end without bifurcation. The cross section of costae is triangular. Internal characters: There were no adequate specimens available for serial sectioning due to the sparry calcite filling. Remarks: Vecchia (1944) erected a new subspecies (Rhynchonella plicatissima rectemarginata) collected from Hettangian rocks. Later Gaetani (1970) raised it to species level. In my opinion the small differences in the external characters do not justify its separation from C. ? plicatissima. Neither the occurrence in Hettangian warrants the separation, as C. ? plicatissima first appears in the Late Hettangian (Aimeras 1964). These specimens are wider and flatter than the Early Sinemurian C. ? plicatissima specimens from the Lókúti-domb (Dulai 1992), however the high variability of this species is well known from the literature. The specimens of Rhynchonella hungarica described by BOckh (1874) are very similar to my specimens. Already Di Stefano (1886), Rothpietz (1886) and Geyer (1889) synonymized R. hungarica Böckh, 1874 with R. plicatissima. In the original description BOckh also mentioned the similarity of the two species but noted that his specimens are wider. It is here regarded to be within the range of intraspecific variability o f C. ? plicatissim a .
