Jb. Keiper et al., Use of algal monocultures by larvae of Hydroptila waubesiana and Oxyethirapallida (Trichoptera : Hydroptilidae), HYDROBIOL, 380, 1998, pp. 87-91
Larvae of the microcaddisflies Hydroptila waubesiana Betten and Oxyethira p
allida (Banks) were given monocultures of eight genera of algae to test the
ir suitability as food sources, and to investigate the degree of trophic sp
ecialization exhibited by these larvae. Only those larvae given green algae
(Chlorophyta) survived and emerged as adults. Oxyethira pallida consumed Z
ygnema and Spirogyra, and exhibited the shortest larval-pupal period on Spi
rogyra (P < 0.05). Similarly, H. waubesiana consumed Zygnema and Cladophora
, but exhibited the shortest larval-pupal period on Cladophora (P < 0.001).
Diatoms and Hydrodictyon allowed H. waubesiana to attain partial growth on
ly, while O, pallida did not consume either alga. Oscillatoria and Anabaena
were not consumed by either species. The larvae of the two species tested
appear to obtain adequate nourishment from only a narrow spectrum of algae,
and one alga allowed significantly faster growth compared to the others te
sted in each case.