On the phylogeny of families and genera within the Temnocephalida

Abstract

Temnocephalida includes species demonstrating many intermediate steps presenting the transition from commensalism to parasitism. Dramatic morphological changes also occurred within this group but the number of supraspecific taxa is small, making the Temnocephalida an excellent model for evolutionary studies. Having summarised original and relevant published morphological data, we suggest a cladogram (phylogenetic tree) which nearly fully resolves the order of branching of families and main genera within the Temnocephalida. We also introduce a new family, the Diceratocephalidae nov. fam.