Biology of Anisocentropus pallidus (Martynov) (Trichoptera, Calamoceratidae): Laboratory and field observations
The biology of the East Asian caddisfly Anisocentropus pallidus (Martynov 1935), Calamoceratidae, was studied in both the laboratory and field in Hokkaido, northern Japan. The egg and early instar larva are newly described. The larvae are abundant in dense accumulations of plant detritus and eat the detritus in littoral areas of ponds in marshes. Their cases are flat, oval and made of two leaf pieces with anteromesal slits, posterior concavities and interior silken chambers. Just after eclosion, a temporary cylindrical tubular case is made of amorphous detritus. The pupal case is also a flattened oval with small anterior and posterior openings on dorsal valves and attached on hard leaves and stems. The prepupal + pupal stage requires 15–19 days at 15–17˚C. Adults appear from June to September with peak emergence during mid June. Females have mature ovaries at emergence. A one− or two-year life cycle is suggested by seasonal changes of instar frequency and larval weight.