PHYLOGENETIC POSITION OF RHYACOPHILOID CADDISFLIES (INSECTA, TRICHOPTERA) - A SPERMATOLOGICAL ANALYSIS OF RHYACOPHILIDAE AND GLOSSOSOMATIDAE

Most caddisflies (Insecta, Trichoptera) are classified into two subord ers, Annulipalpia and Integripalpia. However, the use of the derived c haracters that are regularly applied in systematic and phylogenetic an alyses of Trichoptera is insufficient to determine with certainty the position of the families belonging to Rhyacophiloidea, which are consi dered by different authors to be either Annulipalpia, or Integripalpia , or even a separate suborder. Rhyacophiloidea comprise four overall s imilar families: free-living Rhyacophilidae and Hydrobiosidae, saddle- case making Glossosomatidae, and purse-case making Hydroptilidae. It w as previously found that Annulipalpia spermatozoa have aberrant axonem es while Integripalpia spermatozoa display the plesiomorph 9 + 2 axone me. The present spermatological analysis of the families Rhyacophilida e and Glossosomatidae shows that both have spermatozoa with aberrant a xonemes lacking the two central microtubules found in the typical axon eme of insect spermatozoa. This is an apomorphic character shared with the superfamily Hydropsychoidea, indicating that from this point of v iew, Rhyacophiloidae are more closely related to Annulipalpia than to Integripalpia.