Preliminary cladistic analysis of genera of the cestode order Trypanorhyncha Diesing, 1863

A preliminary cladistic analysis was carried out on the 49 currently recogn ised genera of the order Trypanorhyncha. Forty-four characters were analyse d; a functional outgroup was used for scolex and strobilar characters, whil e Nybelinia was utilised to polarise characters related to the rhyncheal sy stem. Eight well-resolved clades were evident in the resultant cladogram, w hich is compared with existing phenetic classifications. An analysis of fam ilies resulted in a similar clustering of taxa to that observed in the case of the genera. The results suggest that two key characters used in existin g classifications, namely the presence of sensory fossettes on the bothridi a and the development of atypical heteroacanth and poeciloacanth armatures from typical heteroacanth armatures, have occurred on several occasions. So me clades provide support for the arrangements used in current classificati ons. Suggestions are made for future avenues of research which might provid e more robust phylogenetic data for the Trypanorhyncha.