On the relationships of the Normanellidae and the recognition of Cletopsyllidae grad. nov (Copepoda, Harpacticoida)

The phylogenetic relationships of the families of the Laophontoidea are re- assessed in the light of new morphological data on the Normanellidae. The t axonomic concept of the latter is restricted to the subfamily Normanellinae which on account of the morphology of antennule, antenna, mandible, P1, P2 and male P6 is regarded as the most primitive lineage within the Laophonto idea. Cladistic analysis has confirmed HUYS' (1990a) phylogenetic scheme fo r the remaining families. Both sexes of a new genus and species, Bathycletopsyllus hexarthra, are des cribed from 460 m depth off La Reunion. The genus Cletopsyllus Willey is re viewed, resulting in the recognition of two new genera Retrocalcar and Isoc letopsyllus which are based on differences in antennule morphology, male le g 5 armature and sexual dimorphism of swimming legs and caudal rami. Cletop syllus tertius For, 1964 sensu FOR (1967) and C. quartus Soyer, 1966 sensu MARCUS (1976) are considered species inquirendae in Isocletopsyllus whereas Pseudocletopsyllus Vervoort is maintained as genus inquirendum within the Cletopsyllidae. The major morphological transformations and diagnostic char acters of the family are reviewed and a key to genera is presented. Swimmin g leg sexual dimorphism has proved inappropriate for inferring the evolutio nary relationships of the Cletopsyllidae which remain enigmatic at present.