The occurrence of slender leaf pieces on the larval cases of<i>Brachycentrus</i>Curtis, 1834 (Trichoptera: Brachycentridae)
Abstract
Cases of final instar larvae of Brachycentrus kuwayamai Wiggins, Tani and Tanida, 1985 and B. americanus (Banks, 1899) (Brachycentridae) were observed in Hokkaido, northern Japan. Their cases were four-sided, tapered, and constructed of transversely arranged, narrow pieces of plant materials. Slender leaf pieces were fastened longitudinally on cases of final instar larvae of B. kuwayamai, but not on those of B. americanus. In B. kuwayamai, occurrence of the long pieces was variable in populations, with only 1–4 pieces on 32% of the larvae at one site, but 4–18 pieces on 100% of the larvae at another site. The longest attached piece was 3×the case length, and 23 pieces was the most found attached to a single case. This is the first report of attachment of long vegetal pieces to larval cases in the Brachycentridae.