Search

The buccal pouch contents of four deep-water scaphopod (Mollusca) species, Pulsellum affine, Pulsellum teres, Siphonodentalium lobatum and Polyschides olivi, collected in the North Atlantic and the Nordic Seas, were examined. The buccal pouches of the examined scaphopod species contained almost exclusively foraminifers, which agrees with previous studies on shallow and deep-water scaphopods. The scaphopods seemed to be engulfing at least some of the most common foraminifer species, which are distributed in the cold waters of the Nordic Seas or the temperate waters in the northernmost part of the North Atlantic. About half of the food species (30 foraminifer species) occurred in only one scaphopod species, nearly always in very low numbers, and seemed to be an unimportant food source. The remaining and more frequent food species occurred in two or more scaphopod species. A similarity tree was calculated with parsimony and presence-absence coding of the food species in the scaphopods. This resulted in the similarity tree: 100%{P. teres 79%[P. affine 70%(P. olivi and P. lobatum)]}, when branch support was measured with percentage jackknife stability. A general trend was found towards larger food items being consumed by larger scaphopod species, indicated by the positive correlation between the size of the scaphopods and the food species. It is suggested that microdistribution of the foraminifers and the large individual size of the foraminifers may be important factors in avoiding predation by scaphopods.