Goniodelphys Buchholz, 1869

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 : 163

Genus Goniodelphys Buchholz, 1869

Diagnosis: Body consisting of cephalosome, first to fifth pedigerous somites and free urosome. Fourth pedigerous somite fused to fifth and forming brood pouch as long as anterior part of prosome. Free urosome 5-segmented, comprising genital somite and 4 free abdominal somites. Anal somite with paired tapering posteroventral protuberances densely ornamented with minute spinules. Caudal rami armed with 2 claws and 4 setae. Antennule 8-segmented. Antenna 4-segmented; basis with large pinnate seta and small seta (representing exopod); compound distal endopodal segment armed with 10 setae plus terminal claw. Mandible with 5 teeth and 1 or 2 proximal setae on coxal gnathobase, basis with 1 seta; exopod 2-segmented and armedwith 3 and 2 setae on first and second segments, respectively, or unsegmented and armed with only 4 setae; endopod 2-segmented, armed with 4 or 5 and 9 setae on first and second segments, respectively. Maxillulewith 9 setaeon arthrite, 1 seta on coxal endite, 2 setae on epipodite, 3 setae on medial margin of basis; exopod with 3 distal setae; endopod with 4 distalsetae. Maxilla 5-segmented; syncoxawith 3, 1, 2, and 2/3 setae on first to fourth endites, respectively; basis with 3 setae; first to third endopodal segments with 1, 1, and 3/4 setae, respectively. Maxilliped lobate with 10 setae (4 + 4 medial plus 2 apical). Legs 1–4 with 3- segmented exopods and 2- or 3-segmented endopods. Inner coxal seta lacking in legs 1–4. Inner distal spine present on basis of leg 1. Armature formula:

Leg 5 consistingof protopod with 1 seta and exopodal segment bearing 2 setae.

Type Species: Goniodelphys trigona Buchholz, 1869 , by original monotypy.

Remarks. The original description of the type species G. trigona by Buchholz (1869) lacked detail by modern standards but it was redescribed by Illg & Dudley (1965). However, their material was an immature female (Copepodid V) so, although their specimen came from Italian waters (Pozzuoli) close to the type locality (Naples Bay), their redescription provided insufficient morphological information for a robust species comparison. Subsequently Ooishi & Illg (1973) obtained adults of both sexes from Ascidiella aspersa in the Gulf of Trieste. They commented that in the adult female leg 1 was functionally 2-segmented due to the suppression of the articulation between ancestral segments 2 and 3. Legs 2–4 exhibit the same segmentation as in the Copepodid V stage but the segments were more elongate and the setae were better developed. In addition, the 2 claws on the caudal ramus were much more robust than in the Copepodid V.

The genus Goniodelphys remained monotypic for more than a century until Ooishi & Illg (1973) described a second species, G. tokiokai Ooishi & Illg, 1973 , collected from Pterygascidia longa (Van Name, 1918) in the Philippines at a depth of 72 to 80 m. Here we recognize G. tokiokai as the type species of a new genus, Ooishillgia gen. nov. (see below). In their wider discussion, Ooishi & Illg (1973) highlighted the similarities between Goniodelphys , Notopterophoroides Schellenberg, 1922 and the monotypic genus Ustina Illg, 1951 . They reexamined the type material of Ustina clarki Illg, 1951 and concluded that it should be placed in Goniodelphys , as G. clarki ( Illg, 1951) which they formally recognized as a new combination.