Szekessy Vilmos (szerk.): A Magyar Természettudományi Múzeum évkönyve 62. (Budapest 1970)

Nagy, I. Z.: Lower Liassic molluscs from the Mts. Mecsek, Hungary

Chlamys sp. aff. ? lorulosi QUENSTEDT 1026 Chlamys lorulosi QUENSTEDT — STAESCHE, Pectiniden, p. 53, Pl. I, Fig. 1. Examined material: Fragment of a single mold, in grayish black coal shale from Mecseknádasd. Hettangian-Sinemurian, M 69.350. Remarks: The fossil is a very badly preserved shell portion. The apex and the auricles cannot be examined. The costae elongate into very distinct edges, in this respect resembling Ac. acuticosta LAMARCK. On the other hand, the elongated form of the shell is a distinct Chlamys feature. The growth lines between the costae suggest the Formenkreis of the above species. Chlamys ambiguus (MÜNSTER) 1829 P. ambiguus MÜNST. — in Goldf. Petrefact. Germ., p. 46, PL 90, Fig. 5. 1829 P. virgiiliferus PHILL. - Geol. Yorksh. PI. 2, Fig. 2. 1858 P. texiorius QUENST. — Der Jura, p. 500, PL 67, Fig. 5. [936 Chlamys ambiguus MÜNST. — DECHASEAUX, Pect. Jurass., p. 14, PL 2, Fig. 2; PL 3. Fig. 1. Examined material: Fragment of a shell impression in grayish black, sandy coal shale; dump Mecseknádasd. Hettangian-Sinemurian. M 69.344. Remarks: The apical section of the fragmentary specimen is completely missing, but the characteristic sculpture of the species is well recognizable. The costae of the right shell are separated by more or less deep grooves; this finer costal system distinguishes the species from the otherwise very similar Ch. dewalquei OPPEL. The growth lines of the costae are characteristically squamose. Genus: Aequipecten FISCHER, 1886. Aequipecten priseus (SCHLOTHEIM) 1820 P. priseus SCHLOTH. — Petrefactenkde, p. 222. 1830 P. costulatus ZIET. — Verst. Württemberg, p. 68, PL 52, Fig, 3. 1858 P. aequalis QUENST. — Der Jura, p. 78, PI. 0, Fig. 13. 1850 P. aequalis TERQTJEM & PIETTE Lias inf. Fsl France, p. 102, PL 112, Figs. 15618. 1826 Aequipecten priseus (SCHLOTH.) — STAESCHE, Pectiniden, p. 48. Examined material: Two molds, 18 mm and 14 mm high shells in sandy, schistaceous, black coal shale; from hanging marl above coal beds at Mecseknádasd. Lower Sinemurian. M 69.351. Remarks: Rounded specimens with obtuse apices, displaying 18-20 radially situated, simple, unsculptured costae. The anterior auricle is slightly larger than the posterior one, the right shell showing also the emergent canal of the byssus. A cosmopolitan species from the Middle Liassic. The species was listed also by Peters from the higher layers in the Mts. Mecsek. Fam.: Limidae RAFINESQUE, 1815; Genus: Lima CUVIER, 1708; Subgenus: Plagiostoma J. SOWEBBY, 1814.