A method for mass-rearing caddisfly, Cheumatopsyche brevilineata (Iwata) (Trichoptera: Hydropsychidae), as a new test organism for assessing the impact of insecticides on riverine insects

Abstract

This paper introduces a new method for the mass-rearing of a typical riverine insect, Cheumatopsyche brevilineata. This caddisfly could be easily reared continuously under laboratory conditions in rotary-flowing water. The rearing system supported the full life cycle year-round, and the culture scale supplied sufficient larvae for bioassays every week. The hatchability of egg masses dipped at F₃ and F₉ but was otherwise stable at ≥70%. The sensitivity of first-instar larvae to fenitrothion was stable throughout successive generations of a fenitrothion-sensitive strain, and increased gradually in a resistant strain.