Vörös A. szerk.: Fragmenta Mineralogica Et Palaentologica 15. 1992. (Budapest, 1992)

Internal characters: The internal character remains unknown, because only one specimen of this species was found, so there was no possibility for serial sectioning. Remarks: The rather poor preservation of the only specimen renders a more precise identification impossible. Distribution: According to Moore (1965), Phymatothyris is Middle and Late Liassic in age. The specimen of Lókút Hill is Early Sinemurian in age, thus extends the global range of this genus. The genus was reported from Italy, Albania, Greece, the Alps and the Bakony Mountains. Suborder TEREBRATELLIDINA MuiR-WooD,1955 Superfamily ZEILLERIACEA ALLAN, 1940 Family ZEILLERIIDAE ALLAN, 1940 Genus Zeilleria BAYLE, 1878 Zeilleria mutabilis (OPPEL, 1861) (Pl. IV Fig. 6; Pl. V Fig. 1; Text-figs. 27-28) 1861 Terebratula (Waldheimia) mutabilis n.sp. - Oppel: p. 538, pi. 10, fig. 7. 1874 Terebratula (Waldheimia) cfr. mutabilis OPPEL - Böckh: p. 126, pl. 1, figs. 3-9. 1889 Waldheimia mutabilis OPPEL - Geyer: p. 18, pi. 2, figs. 31-36, pi. 3, figs. 1-7. 1895 Waldheimia mutabilis OPPEL - Fucini: p. 206, pi. 7, figs. 29-31. 1907 Waldheimia mutabilis OPPEL - Dal Piaz: p. 48, pi. 3, fig. 7. 1912 Waldheimia (Zeilleria) cf. mutabilis OPPEL - Haas: p. 273, pi. 20, figs. 14-15. 1943 Waldheimia mutabilis OPPEL - Vígh: p. 31, pl. 1, figs. 9-14. 1964 Zeilleria mutabilis OPPEL - Siblik: p. 165, fig. 2. 1967 Zeilleria mutabilis OPPEL - Sacchi Vialli and Cantaluppi: p. 108, pi. 15, fig. 10. non 1883 Waldheimia mutabilis OPPEL - Canavari: p. 92, pi. 10, figs. 9-10. Dimensions (mm): Specimens M.91.26 .(Text-fig. 27a) and M.91.27. (Text-fig. 27b) length: 15.2, 17.2; width: 14.1,15.5; thickness: 9.7,8.4. Material: 47 complete specimens. a) Description - External characters: The size and the outline of this species are extremely variable. It is best described by two characteristic extremes within which there is a full range of morphological transitions. Text-fig, 27 - Drawing of Zeilleria mutabilis The first characteristic form is nearly regular pentagonal in outline. The antero-lateral corners are slightly