Untold diversity: the astonishing species richness of the Notodelphyidae (Copepoda: Cyclopoida), a family of symbiotic copepods associated with ascidians (Tunicata)

Abstract

Detailed study of the Monniot collection of copepods belonging to the family Notodelphyidae has revealed an extraordinary diversity of novel taxa. With rare exceptions notodelphyids live in association with ascidians and the Monniot collection was built up over several decades of field collecting and taxonomic research on the ascidian hosts by Drs Claude & Françoise Monniot (MNHN, Paris). This paper describes a total of 178 new species of notodelphyids from ascidian hosts and 37 new genera are established: Bathynotodelphys gen.nov., Pronotodelphys gen. nov., Ooishillgia gen. nov., Nobinerilla gen. nov., Notopygus gen. nov., Chelipygus gen. nov., Sympygus gen. nov., Vaoda gen. nov., Gosbia gen. nov., Pentachaetus gen. nov., Diceratus gen. nov., Prodoroixys gen. nov., Notoixys gen. nov., Borixys gen. nov., Cystixys gen. nov., Ammonixys gen. nov., Ctenixys gen. nov., Ademoixys gen. nov., Gallincola gen. nov., Scoliosoma gen. nov., Contoura gen. nov., Unimeria gen. nov., Mecodelphys gen. nov., Tubipedia gen. nov., Procampodelphys gen. nov., Janius gen. nov., Campodelphys gen. nov., Hamaticoxa gen. nov., Adrodelphys gen. nov., Phyllodelphys gen. nov., Lissodelphys gen. nov., Nodoscarus gen. nov., Diblastus gen. nov., Chilodelphys gen. nov., Scaridelphys gen. nov., Socotradelphys gen. nov., and Aplodelphys gen. nov. Prior to this study the Notodelphyidae comprised exactly 200 valid species classified in 46 genera, a mean species richness of 4.3 species per genus. After the addition of the new taxa described here, the family now comprises 378 species in 83 genera, a mean species richness of 4.6 species per genus. Generic diagnoses are provided for all genera represented in the collection and the availability of a wider range of taxa has allowed certain generic boundaries to be better defined, resulting in transfers of species between genera and the recognition of 16 new combinations. A further 51 existing species are also reported, and brief supplementary notes or full redescriptions are provided as appropriate.