Phylogeny and classification of the Conochilidae (Rotifera, Monogononta, Flosculariacea)

To resolve several taxonomic problems within the family Conochilidae (Rotif era, Monogononta, Flosculariacea), we initiated a comparative study of the morphology in this and related taxa using samples collected from widely sep arated geographical regions. As part of this study, we paid special attenti on to trophal morphology using scanning electron microscopy. We also constr ucted and analysed a data matrix comprising 19 morphological characters of 11 taxa using cladistic methods to uncover all most-parsimonious trees. The results indicate that Conochilidae share a body form with Flosculariidae, but they possess a trophal structure which clearly differentiates them from all other Flosculariacea; thus, the diagnosis of the family Conochilidae i s amended to incorporate morphological characters of the trophi. The analys is of our data matrix yielded a single, most-parsimonious tree. From the to pology of that tree and our scanning electron microscopy observations, we p ropose the following: (1) the status of Conochilidae as a separate suborder of Flosculariacea is rejected; (2) taxonomic separation of Conochilus and Conochiloides as subgenera of Conochilus is confirmed; and (3) Lacinularia causeyae Vidrine, Mclaughlin & Willis, 1985 is reallocated to a new genus w ithin the family Conochilide, Conochilopsis gen. nov., as Conochilopsis cau seyae (Vidrine et al.) comb. nov.