Published online by Cambridge University Press: 31 May 2012
The Rhyacophila coloradensis complex is discussed and a new species, amabilis, is added to the group. Two new species of Rhyacophila are described from California, spinata and ardala. Four new species of Limnephilus are described from California, bucketti, catula, atercus and neoacula; the first three represent interesting variations from described species. Several Limnephilus females are associated with the described males.