Vörös A. szerk.: Fragmenta Mineralogica Et Palaentologica 16. 1993. (Budapest, 1993)

Order TEREBRATULIDA Waagen. 1883 Suborder TEREBRATUL1DINA Waagen. 1883 Supcrfamily TEREBRATULACEA Gray. 1840 Family Tchegemithyrididae Tchorszhevsky. 1972 Subfamily Lobothyridinae Makridin. 1964 Genus Lobothyris Buckman, 1918 Lobothyris ovatissimaeformis (Böckh. 1874) (Plate 1: Fig. 6; Text-fig. 7-8) 1874 Terebramla ovatissimaeformis n. sp. - Böckh: p. 123. pl. 1, figs. 11-14. 1903 Terebramla ovatissimaeformis Böckh - De Alessandri: p. 243. fig. 1. 1970 Lobothyris ovatissimaeformis Böckh - Gaetani: p. 348, pl. 30, figs. 2-6. Material: Kőris-hegy (20 specimens). Páskom ( 10), Cuha-völgy ( 12), Szesztra-hegy (27). Eperkés-hegy (4), Lókúti-domb (5), Kávás-hegy (11), Som-hegy ( 13), Alsó-Hajag (8), Tűzköves-hegy (14), Csalános-völgy (3) and Sümeg (1 ). Dimensions (mm): Specimen M.93.9. (Text-fin. 7) length: 21.6. width: 14.4. thickness: 10.3. Description - External characters: Medium to large sized shell, elliptical in outline but slightly angular at the anterior margin. The anterior margin is straight. The length is much larger than the width, while the thickness is three-quarter of the length. The angle between the lateral margins is about 80°. Biconvex form, the convexity of valves is equal. The maximum width and the maximum convexity are situated at the half of the length. The beak is small and erect. There arc two weak beak ridges on the pedicle valve running to the third of the length. The lateral commissures and the anterior commissure are straight. The shell surface is smooth. Internal characters (Text-fig. 8): The pedicle collar is missing but it is present at some other specimens. There are no dental plates. The delthyrial cavity is circular in cross section. The hinge-teeth are small and not crenulated. No median septum has been observed. The sockets are narrow and deep at the beginning but wider and shallower after that. The inner hinge plates are straight at the beginning and slightly arched after that. The crural processes are high but not too wide. The transverse band is high and narrow. There is a frilly secondary callus at the end of transverse band. Remarks: This species is the most common in Kardosrét Limestone Formation. The external characters are quite variable. Already in Böckh's (1874) original description several different forms were figured. Böckh's original type specimens are missing from the type material of the Hungarian Geological Institute. The internal characters refer to the genus Lobothyris, just as in the case of Gaetani's (1970) specimens from Bergamo. Distribution: According to Aimeras (1964), L. ovatissimaeformis is Hettangian to Early Sinemurian in age. Gaetani (1970) described it from Hettangian rocks. The species was reported from the Southern Alps and the Transdanubian Central Range. Icxt-tig. 7: Drawing ai Lobothyris ovatissimaeformis, Kőris-hegy