INCORPORATION OF BATRACHOSPERMUM-GELATINOSUM (RHODOPHYTA) INTO CASES OF OCHROTRICHIA-WOJCICKYI (TRICHOPTERA, HYDROPTILIDAE)

Microcaddisfly larvae (Trichoptera: Hydroptilidae) often incorporate f ilaments of algae into their cases (Wiggins 1996). Sheath et al. (1995 ) studied the incorporation of freshwater red algae (Rhodophyta) into the cases of a variety of caddisfly species. They reported that hydrop tilid larvae of Dibusa, Hydroptila, and Ochrotrichia had Rhodophyta in corporated into their cases, but no Ochrotrichia were identified to sp ecies. To supplement their study, we report the incorporation of the r hodophytan Batrachospermum gelatinosum (L.) De Candolle into the cases of Ochrotrichia wojcickyi Blickle. Although B. gelatinosum has been a ssociated with the cases of midge larvae (Diptera: Chironomidae) (Shea th et al. 1996), this is the first report of B. gelatinosum used as ca ddisfly case material. Larvae were collected from cobble substrata in an unnamed low order stream located in Salt Fork State Park (40 degree s 06'03 N,81 degrees 28'41 W), Guernsey Co., Ohio, on 26 May 1997. The y were transported to the laboratory, placed in aerated rearing chambe rs (Keiper and Foote 1996) with field-collected riffle rocks, and the adults reared for species determination. Larvae were never observed to consume B. gelatinosum in the laboratory. Living algae covered approx imately 5-15% of cases examined. Sand grains often constitute most of the case material used by larvae of Ochrotrichia (Wiggins 1996). The i ncorporation of B. gelatinosum into the cases of the specimens collect ed suggests that O. wojcickyi is not specific in its case material req uirements. The fate of living Rhodophyta incorporated into caddisfly c ases remains unknown.