Diptères torrenticoles peu connus: III. - Les Athericidae du sud de la France (Régime alimentaire des larves: Aspect qualitatif) [Brachycera, Orthorrhapha]

Abstract

An experimental study in both flowing water and a closed aquarium showed that larvae of Atherix ibis are polyphagous, feeding on the larvae of torrential insects with thin chitin: Ephemeroptera (Baëtidae, Heptageniidae), Trichoptera (Philopotamidae), Diptera (Limoniidae, Chironomidae). Digestion is extra-oral and the suction time is a function of the relative sizes of the prey and predator, varying from about fifteen minutes to about two hours. For all stages with a length greater than 4 mm, the buccal apparatus is effective on a large size range of prey. The intensity of predation by larvae of A. ibis on a population of older Chironomidae is a linear function of the size of the predators between 5 and 15 mm.Cannibalism rarely occurs when the larvae are not deprived of food. The older specimens can endure a period of six months without food at 10-15 °C.Some observations have also been made on the food of Atrichops crassipes. © 1975 Masson.