Food consumption by the larvae of Sericostoma vittatum (Trichoptera), an endemic species from the Iberian Peninsula

The caddisfly Sericostoma vittatum Rambur (Trichoptera: Sericostomatidae) i s an endemic species of the Iberian Peninsula. Under laboratory conditions, larvae of S. vittatum had a higher activity and metabolism during the nigh t. Besides consuming particulate allochthonous organic matter, young stages are also able to feed and grow on faecal pellets from adults. Daily growth rates varied from 0.02 mg (0.8-3.7 mg size class animals) to 0.31 mg dry m ass (10.6-22.8 mg size class animals). Due to the high densities of this sp ecies (annual mean of 25 individuals m(-2); maximum of 96 individuals m(-)2 ) and high consumption rates (0.47 mg leaf dry mass mg animal(-1) d(-1) for small larvae), this species has a potential key role on the fragmentation of allochthonous organic matter of streams in central Portugal.