Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 73. (Budapest 1981)
Vörös, A.: A survey of the Rhaetian (Upper Triassic) Bivalvia from Borzavár (Bakony Mts., Hungary)
arched anterior and truncated posterior margins. The specimens from Borza vár and those figured by VÉGH (I.e.) correspond well to this picture. Some Italian authors described a series of forms, under the name M. isosceles, which can hardly or not be included into this species. The pl.XXV., fig.5-6. in ALASSINAZ (I.e.), pl.I., fig.10-11. in GELATI and ALASSINAZ (I.e.) and pi. 55., fig. 9. in SIRNA (I.e.) perhaps represent juvenile or fragmentary specimens which therefore do not show features characteristic to M. isosceles. On the other hand, the specimen figured by ALASSINAZ (I.e., pl.XXV., fig.4.) can be regarded as a typical representative of our species. Distribution : Rhaetian of the "Préalpes" (?), the Southern Alps, the Appennines (?) and the Bakony Mts. (Hungary). Genus PSEUDOCORBULA PHILIPPI, 1898 Pseudocorbula ewaldi (BORNEMANN, 1854) (Plate II: 11) *1854: T. [aeniodon] Ewaldi BORNEMANN, Göttingen, p. 66. 1856: Opis cloacina — QUENSTEDT, Der Jura, p. 31, pl. I, fig. 35. 1856: Schizodus cloacinus QUENST. sp. — OPPEL et SUESS, Über die Äquivalente, p. 9, pl. II, fig. !.. 1861 : Schizodus cloacinus QUENST. —WINKLER, Oberkeuper, p. 475, pl. VII, fig. 6a-d. 1861 : Axinus cloacinus. — MOORE, Avicula contorta Zone, p. 502, pl. XV, fig. 16. 1863: Myophoria Stenonis STOPP.—STOPPANI, Couches à Avicula. .., p. 129, pi. 30, fig. 6. 71863: Nucula sp. — Ibid., p. 131, pi. 30, fig. 16 1868 : Protocardia Ewaldi BORN. sp. — PFLÜCKER Y RICO, Göttingen, p. 415, pl. VII, fig. 6. 71870: Schizodus Ewaldi DITTMAR. — FISCHER-OOSTER, Thun, p. 64, pl. II, fig. 21a-d. 1908: Isocyprina cf. ewaldi, BORNEMANN sp. — HEALEY. Napeng Beds Burma, p. 65, pl. IX, fig. 13-14, 15. (7). vl964: Isocyprina ewaldi (BORNEMANN), 1854 — VÉGH, Rhät. Südl. Bakonygeb., p. 42, 80. 1967: Isocyprina (?) ewaldi (BORNEMANN, 1854) — KOCHANOVÁ, Rhaet-Hettang-Grenze, p. 79. pl. II, fig. 4. Material : 19 specimens (3 almost complete shells and 16 internal casts). — Locality : Borzavár, Rhaetian yellow limestones. Dimensions (mm): length: 10.5 8.8 7.8 7.6 5.0 height: 8.2 7.1 6.1 5.5 4.3 Description : Very small, strongly inflated shell with slightly inequilateral, subtrigonal outline. The umbo is prominent and lies anteriorly but near to the mid-length. The posterodorsal and the posterior margins are straight and form an obtuse angle. After a pointed posteroventral corner, the ventral margin is evenly arched and passes gradually into the anterior one. A distinct carina runs from the umbo to the posteroventral corner. An elongate escutcheon is present between the umbo and the posterodorsal corner. The area between the carina and the escutcheon ridge shows two indistinct radial riblets. The flank and the area are ornamented with very fine, regular growth ines. Remarks: P. ewaldi was described but not figured by BORNEMANN (I.e.), therefore its junior synonym P. cloacina (QUENST.) became widely used. Later on, the identity of the two forms and the priority of BORNEMANN'S name became generally accepted (e.g. : DITTMAR 1864, p. 174; PFLÜCKER Y RICO I.e.). STOPPANI (I.e.) described a couple of specimens under different names which seem to belong to P. ewaldi. The generic position of this species has been changed several times. One of the reasons for this was apparently the very small size of the specimens under investigation which made difficult to interpret the character of hinge morphology. In this respect, the material from Borzavár did not give new results but the characteristic outline, the distinct carina and the presence of the escutcheon strongly support its assignment to Pseudocorbula. (These characters are alien to Isocyprina.) Distribution : Rhaetian of the British Isles, Germany, the "Préalpes", the Northern and the Southern Alps, the Western Carpathians, the Bakony Mts. (Hungary) and Burma.
