THE GENERAL CLASSIFICATION OF PARASITIC P LATYHELMINTHES - RECENT CHANGES, AND THE USE OF ULTRASTRUCTURAL CHARACTERS, PARTICULARLY THOSE OFSPERMATOZOA

The classification of parasitic Platyhelminthes (= Aspidogastrea, Dige nea, Monogenea, Amphilinidea, Gyrocotylidea and Eucestoda) has greatly changed in the past twenty years, because of the use of the cladistic method and of the description of new characters, particularly those d ealing with ultrastructure. Among these new characters, spermatozoal c haracters are especially numerous and informative, because of the grea t variability of male gametes in the Platyhelminthes. The cladistic cl assification of the Platyhelminthes is presented. Examples of synapomo rphies defined upon spermatozoal ultrastructure are given for the Trep axonemata, the Temnocephalidea, the Eucestoda, and the Cyclophyllidea.