Vörös A. szerk.: Fragmenta Mineralogica Et Palaentologica 18. 1996. (Budapest, 1996)

Material: 24 specimens. Stratigraphical and geographical distribution: L. Toarcian, Germany. Bythocypris symmetrica sp. n. (Pl. VI: 2) Derivatio nominis: After its nearly symmetrical form. Locus typicus: Hamuháza. Stratum typicum: Domerian, Stokesi Zone. Diagnosis: Narrowly rounded anterior and posterior, very broadly and symmetrically rounded dorsal, straight ventral outline. Description: The anterior outline of the left valve is rather narrowly and symmetrically rounded, the dorsal arch is nearly symmetrical and very broad, the posterior outline is somewhat asymmetrical, its lower part has a shorter radius, the posterior end is narrower as the anterior one, the ventral outline is straight. On the right valve the anterior, median and posterior parts of the dorsal outline are straight, the ventral outline is fairly and symmetrically concave. The overlap is dorsal and medioventral. The surface of the valves is smooth. Comparison: Somewhat similar are Bythocypris? sp. in BRAND (1990, pp. 147148., Pl. 1., f.10.), Bythocypris sp. in ROSENFELD & HONIGSTEIN (1991, p. 137., Pl. 1., f. 6-7). Dimensions: L = 0.55 - 0.97 mm, H = 0.26 - 0.42 mm, L/H = 2.12 - 2.31 Material: 10 specimens. Genus Isobythocypris Apostolescu, 1959 Isobythocypris ? postera Herrig, 1979 (Pl. VI: 3-4) 1959. 1 Isobythocypris elongata (Tate et Blake, 1876) - APOSTOLESCU, p. 808., Pl. II., f. 24-25. 1979. Bairdiacypris traissica postera n. sp. - HERRIG 1979a, pp. 776-778., Abb. 11-12., Pl. f. 15-18 pars. 1979. Bythocypris? cylindrica n. sp. - HERRIG 1979c, pp. 1345-1347, Abb. 4 (pars). 1989. Isobythocypris cf. cylindrica Herrig, 1979 - RUTHERFORD & AlNSWORTH, PI. 1. f. 5. 1993. Bythocypris postera (Herrig, 1979) - HARLOFF, pp. 62-63., PI. 3., f. 6. 1994. Bythocypris postera (Herrig, 1979) - HARLOFF & JÄGER, p. 20., PI. 4. f. 7. Remarks: There are no specimens in this material with inner features visible. On the basis of the outline some "young forms" of Bythocypris cylindrica in HERRIG (1979) belong to postera. The postera specimens figured in HARLOFF (1993) and HARLOFF & JÄGER (1994) are somewhat longer and more acute posteriorly, but similar forms are present in the Pliensbachian material of the Bakony Mts. with a transition to the typical form. Dimensions: L = 0.65 - 0.93 mm, H = 0.34 - 0.46 mm, L/H = 1.85 - 2.03