Published online by Cambridge University Press: 15 February 2009
The first list of Trichoptera from lakes Vico and Bolsena is reported. It is the result of research carried out in 1955 and 19711979 in lake Vico, and in 1957 and 1959-1990 in lake Bolsena. The distribution of caddisflies around the littoral zone depends on the environmental characteristics of the microhabitats. Overall, 16 species from 7 families were collected, 8 of which were found in both lakes, whereas 5 were only collected in Lake Vico, and 3 only occurred in Lake Bolsena. Hydroptila aegyptia and Ecnomus tenellus were the most abundant species in Vico, Tinodes waeneri and T. maclachlani in Bolsena. The trophic categories of the larvae and their gregarines were identified.