Palaeoecology of some mollusca from the Tielrode sands (Pliocene, Belgium)

Abstract

Borings and other types of shell damage are studied in the Pliocene Tielrode malacofauna. These investigations show that the Astarte species as well as a small Cardita lived directly under the sediment surface, and did not wander. The exact living positions of these four species could be determined; that of the Cardita was somewhat anomalous. Cyprina and Pygocardia lived on the sea bottom, as did Nassarius labiosus probably dwelt in the sand; Turritella triplicata lived lifetime. Nassarius labiosus probably dwelt in the sand; Turritella triplicata lived there also and was a prey for naticid snails and crabs. Polinices searched for food in the sediment, but was threatened by cannibalism and crustaceans. An estimate of the depletions caused by the latter could be made. The shell often served pagurid crabs, that carried Electra as principal epibiont on the shell. Neptunea and Thais lived exclusively on the sea bottom; only the shells of the latter were inhabited by hermit crabs, as the Neptunea is sinistrorsal. Both gastropods developed protecting shell layers against boring epibionts. In the introduction some examples are given of investigation of shell borings; the general features of the Tielrode deposit are described. In the discussion, possibilities and limitations of the method are dealt with. © 1967.