Az Eszterházy Károly Tanárképző Főiskola Tudományos Közleményei. 1994. Sectio Geographiae.(Acta Academiae Paedagogicae Agriensis : Nova series ; Tom. 21)

Dávid Árpád: Palaeo-occological and palaeo-pathological observations on upper oligocene molluscs (Eger, Hungary)

Hinia schlotheimi (Beyrich), Ringicula aurículata paulicciae (Morlet), Scaphopoda: Dentalium simplex (Michelotti), Bivalvia: Corbula basteroti (Homes), Corbula gibba (Olivi), Pitar polytropa (Anderson), Nucula mayeri (Hörnes), Ostrea cyathula (Lamarck). There are two kinds of borings. According to the scientific investigations this indicates the activity of two different species. 1. The cylindriform and cone-shaped boreholes are made by muricid gastropods. 2. The borings which converge toward the center of the inner opening sign the activity of naticid gastropods (BISHOP, G.A. 1975). The author could collect numerous fossil claws. I supposed that I could discover the feeding traces of crabs, too. I have found two gastropod shells with signs of crab's activity. The shells belong to the next species: Ampullina crassatina (Lamarck), Turricula reguláris (Köninck). In case of both specimen we can see the characteristic damage, the extreme opening, which begins at the mouth of the gastropod and extends over several whorls. Such damage to the snail is caused by crabs to reach the soft parts of the body. The dimensions of the openings show that the meeting with the crabs was fateful for both gastropods. These observations refer to a former shallow-water marine enviroment. Similar phenomenon can be studied under recent conditions in the coastal regions of subtropical and mediterranean seas. 38