Predatory behaviour of Aquatides thornei (Nygolaimina: Nematoda)

Abstract

Studies on its predatory behaviour revealed that Aquatides thornei was not attracted towards live nor bisected prey nematodes, but made contact with the prey by chance: labial contact was necessary to initiate an attack. Several predators aggregated and fed on prey injured by another predator. No preference was shown for any part of the body for attack; Rhabditis sp. was selected in preference to Chiloplacus symmetricus. A. thornei seemed to paralyse the prey after its mural tooth was inserted deep into the body. Ingestion was intermittent with short periods of sucking activity, the duration of feeding on a single prey varied from 3-5 min to 4-6 h. Little variation was found in the daily rate of predation during 12 days. The rate of predation increased as the number of prey increased. Maximum predation occurred with 150 prey and least with 25 prey nematodes.