SPERM STRUCTURE OF TRICHOPTERA .1. INTEGRIPALPIA, LIMNEPHILOIDEA

Spermal ultrastructure in 16 caddisflies (Trichoptera) belonging to th e suborder Integripalpia, superfamily Limnephiloidea, was examined in a search for apomorphic and plesiomorphic features. In all species exa mined, the sperm tail axoneme was of the 9 + 9 + 2 + type, the axonema l doublets lacked outer dynein arms but had inner ones, and the cell m embrane was scalloped with a prominent glycocalyx. The number of proto filaments in the accessory tubules depended on the phylogenetic positi on: 18 in the family Leptoceridae, 19 in Limnephilidae, Goeridae and O dontoceridae (with a reduction in the number distally), and 20 in Seri costomatidae. Spermatozoa in Leptoceridae are further characterized by the 2 central microtubules being flattened and eccentric and not bein g surrounded by a central sheath. Spermatozoa of Sericostomatidae have an accessory body and a helicoidal array of the sperm tail.