I present a key for the identification of pupae and pupal exuviae of six species of Hydropsyche that are widely distributed throughout northeastern North America and that are particularly abundant in the streams of southern Ontario. Use of the pupal key requires less manipulation of a specimen than either removing larval sclerites from the pupal case or attempting to discern the adult genitalia through the pupal integument.
Rutherford, Jane E.
"An Illustrated Key to the Pupae of Six Species of Hydropsyche (Trichoptera: Hydropsychidae) Common in Southern Ontario Streams,"
The Great Lakes Entomologist: Vol. 18
, Article 2.
Available at: http://scholar.valpo.edu/tgle/vol18/iss3/2