Some new parasitic copepods (Siphonostomatoida: Nicothoidae) from deep-sea asellote isopods

Summary

The highly transformed siphonostomatoid Choniorhiza enaulis gen. et sp. nov. is described from an asellote isopod, Dendromunna sp., in the deep North Atlantic Ocean to the south west of the Azores. Male and female live inside a cyst on the dorsal side of the branchial chamber of the isopod. The new genus may be distinguished from all other genera of the Nicothoidae, except Rhizorhina, by the presence of oral processes replacing the cephalic appendages. It differs from Rhizorhina in the presence of a distinct urosome in the female. A key to all genera of the Nicothoidae is provided and Pseudonicothoe Avdeev & Avdeev is recognized as a junior synonym of Paranicothoe Carton. The male syntype of Paranicothoe cladocera Carton is designated as the lectotype because the female is an isopod. Sphaeronella bradfordae sp. nov. is described from an isopod of the genus Haploniscus caught on the Chatham Rise off New Zealand.