Adrodelphys, Kim & Boxshall, 2020

Kim, Il-Hoi & Boxshall, Geoff A., 2020, Untold diversity: the astonishing species richness of the Notodelphyidae (Copepoda: Cyclopoida), a family of symbiotic copepods associated with ascidians (Tunicata), Megataxa 4 (1), pp. 1-6 : 621-623

Adrodelphys gen. nov.

Diagnosis. Body maggot-like, consistingof unsegmented prosome and small indistinctly 4-segmented urosome. Caudal rami completely fused with last abdominal somite, lacking caudal setae. Rostrum well-developed. Antennule short, 3-segmented with small terminal segment. Antenna 3-segmented withsmallterminalclaw. Mandiblebiramous and unsegmented; coxa with short, unarmed gnathobase; palp comprising exopod fused with basis, armed with 5 setae, plus endopod also fused with basis and armed with 7 setae. Maxillule consisting of precoxa and biramous palp; precoxal arthrite with 5 setae; palp with 1 seta on epipodite, 2 on basis, 4 on exopod, and 3 on endopod. Maxilla distinctly 5-segmented with 3 endites on syncoxa, 1 seta only on basis, and 1, 1, and 3 setae on first to third endopodal segments, respectively. Maxilliped as small lobe bearing 2 setae distally. Legs 1 and 2 rudimentary, but setiferous. Legs 3-5 absent.

Type species. Adrodelphys tectifera gen. et sp. nov. by original designation.

Etymology. The generic name is derived from the Greek adr (=stout) and - delphys, the ending of many generic names in the family Notodelphyidae , referring to the stout body of the type species. Gender feminine.

Remarks. The establishment of this new genus is justified mainly by the characteristic unsegmented form of the mandible in which the coxal gnathobase is short with a truncate but unarmed medial margin. This gnathobase appears to be non-functional and no similar form of mandibular gnathobase has been reported from any other genus in the Notodelphyidae .

In the presence of all mouthparts plus legs 1 and 2, the new genus is comparable with Sicyodelphys Lafargue & Laubier, 1968 . The major differences from Adrodelphys gen. nov, are that Sicyodelphys has a uniramous mandible lacking the coxal gnathobase, an unsegmented maxillule, and biramous butunarmed legs 1 and 2.