Dr. Fűköh Levente szerk.: Malakológiai Tájékoztató 14. (Eger, 1995.)

DÁVID, Á.: Naticid prédation on Late-Oligocene (Egerian) corbulid bivalves collected from three localities of NE - Hungary

Discussion The location of boreholes on the Corbula valves doesnt show any regularity. Boreholes are most frequent on the right valves. The number of multiplied borings is three. The activity of naticids increase with the growth of the grain-size of the sediment. The size of Corbula gibba Olivi is less than the size of the other species. Complete boreholes, however more frequent than in the case of Corbula basteroti Homes. According to some outhors naticid prédation on corbulid bivalves is anomalous because of the conchiolin sheets within the valves of corbulids (defence) (Anderson, L. C. 1992). Results of the examination of the above mentioned data shows that the role of conchiolin sheets in the defence of corbulids not so significant as it was thought before. REFERENCES Anderson, L. C. (1992): Naticid Gastropod Prédation on Corbulid Bivalves: Effects of Physical Factors, Morphological Features, and Statistical Artifact Palaios V. 7: 602-620. Ansell, A.D. - Morton, B. (1983): Aspects of Naticid Prédation in Hong Kong with Special Reference to the Defensive Adaptations of Bassina (Callanaitis) calophylla (Bivalvia) in: Morton, B. and Dudgeoon, D. (eds.). - The Malacofauna of Hong Kong and southern China. 2: 635-660. Báldi, T. (1973): Mollusc fauna of the Hungarian Upper Oligocène (Egerian). - Akadémiai Kiadó, Budapest, p: 511. Báldi, T. (1983): Magyarországi oligocén és alsómiocén formációk . - Akadémiai Kiadó, Budapest, p: 293. Báldi, T. - Báldiné Beke, M. (1974): A novaji típusszelvény (kiscellien-egerien) nannoplanktonjaés makrofaunája. - Földtani Közlöny 104: 60-88. Harper, E. M. (1994): Are Conchiolin Sheets in Corbuloid Bivalves Primarily Defensive?. - Paleontology, 37. 3: 558-578. Kitchell, J.A. et. al. (1981): Prey selection by naticid gastropods: experimental tests and application to the fossil record . - Paleobiology, 7 (4): 533-552. Dávid Á. Eger, Faiskola u. 6. H-3300