Mecodelphys, 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 : 572

Mecodelphys gen. nov.

Diagnosis. Body Doropygus -like. Prosomal somites divided only by weak constrictions; third and fourth pedigerous somites fused, forming inflated brood pouch. Free urosome clearly 5-segmented, inserted into ventral side of brood pouch. Caudal ramus armed with small setae. Rostrum well-developed. Antennule incompletely segmentedwith reduced setation. Antenna 3-segmented with small terminal claw. Labrum distinct. Mandible consistingof biramous palp only; exopod and endopod fused to basis, lobate, unsegmented, each armed with 4 setae. Maxillule, maxilla and maxilliped each represented by single lobe bearing 1 to few setae. Legs 1–4 biramous with extremely long, unsegmented rami; setation reduced. Leg 5 represented by 2 processes each bearing 1 seta.

Type and only species. Mecodelphys edentatus gen. et sp. nov. by original designation.

Etymology. The generic name is derived from the Greek meco (=long) and - delphys (a common ending for genera in the family) and refers to the elongate swimming legs of the new genus. Gender masculine.

Remarks. The body of Mecodelphys gen. nov. is similar to that of Doroixys , but its mouthparts and legs are entirely different from those of Doroixys and the other genera in the Doroixys -group. Although the characteristically elongate and unsegmented rami of legs 1–4of Mecodelphys gen. nov. are sharedby Unimeria gen. nov., they display several other important morphological differences. In Mecodelphys gen. nov. the urosome is distinctly 5-segmented whereas it is unsegmented in Unimeria gen. nov. The mandible of Mecodelphys gen. nov. lacks the coxal gnathobase and its exopod and endopod are both fused to the basis whereas the mandible of Unimeria gen. nov. has a pectinate coxal gnathobase and has a free exopod and endopod. The maxilliped is present in Mecodelphys gen. nov. but absent in Unimeria gen. nov., and leg 5 is present in Mecodelphys gen. nov. but absent in Unimeria gen. nov.