We investigated the distribution patterns of Rhyacophila larvae at 2 habitat scales in mountain streams in central Honshu. One was at a rapid glide within a stream reach and the other was in microvertical layers within each rapid and glide. Cobbles were predominant in rapids, whereas sand and gravels were predominant in glides. Mean sediment particle size was smaller in glides, but evenness of sediment size and porosity were greater. A total of 9 species of Rhyacophila larvae were collected from rapids. On the other hand, in glides, only 4 species, R. nipponica, R. shikotsuensis, R. kawamurae, and R. transquilla, were collected, but they were more abundant than in rapids. The larvae of R. transquilla were found mainly in upper layers of the stream bed, whereas the other 3 species, R. nipponica, R. shikotsuensis, and R. kawamurae, occurred both in upper and lower layers. The latter 3 species belong to R. nigrocephala species group, the larvae of which share several common morphological and behavioral characters adapted to hyporheic habitat, such as slender body shape and vermicular movement. It is suggested that higher porosity in glides provides more microhabitat for them, and small-sized sediment particles are appropriate for their burrowing and creeping movement in hyporheic habitat.