Unimeria longipedata, 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 : 570-572

Unimeria longipedata gen. et sp. nov.

( Fig. 382 )

Type material. Holotype ♀ (dissected and mounted on a slide, MNHN-IU-2014-21418 ) from the colonial ascidian Leptoclinidesapertus Monniot F., 1989 (MNHN-IT-2008- 4767 = MNHNA2/LEP/20), Rocher à la Voile , Noumea , NC45, New Caledonia, depth 9-10 m, Monniot coll., 19 March 1987.

Etymology. The specific name refers to the long, digitiform rami of legs 1–4.

Description of female. Body ( Fig. 382A ) unsegmented; bodylength (prosome length) 2.43 mm. Prosome undivided, elongate, gradually broadening posteriorly, with rounded posterior margin; dorsoventral depth of posterior part 936 μm. Cephalosome obscurely defined by slight lateral constriction. Free urosome ( Fig. 382B ) short, unsegmented, widerthan long, directed perpendicular to prosome, not articulated from prosome, inserted into posteroventral surface of brood pouch. Caudal ramus ( Fig. 382C ) not articulated from urosome, strongly tapering, slightly longer than wide (63×52 μm); armedwith 6 naked setae.

Rostrum( Fig.382D )weak,flexible,broadproximally, narrow and tapering distally; denselycovered with setules. Antennule ( Fig. 382E ) also densely ornamented with setules, incompletely 2-segmented; broader first segment armedwith 17 small setae, narrower, tapering second segment with 8 setae. Antenna ( Fig. 382F ) 3-segmented; coxa and basis unarmed; unsegmented endopod narrow, 3.6 timeslongerthan wide (160×44 μm) and longerthan basis; armed with 6 small setae (2 at proximal 40% on inner margin, 2 subdistal, and 2 distal) plus very small terminal claw, 0.25 times as long as endopodal segment.

Labrum ( Fig. 382G ) broad, unornamented, with convex posterior margin. Mandible ( Fig. 382H ) with coxalgnathobase slightly narrowing medially; medial margin nearly straight, pectinate, with 1 minute tooth distally: palp consistingof basis (basis+first endopodal segment) armed with 2 setae; exopod and endopod each with 4 setae. Maxillule ( Fig. 382I ) as single lobe bearing 10 densely plumose setae (medial 3 shorter than others). Maxilla ( Fig. 382J ) strongly curved, incompletely 3- segmented; armed with 4, 1, and 2 setae on first to third segments, respectively. Maxilliped absent.

Legs 1–4 ( Fig. 382 K-N) biramous, unsegmented with elongate digitiform rami covered with setules; rami lacking any trace of articulation; endopods shorter than exopods. Exopods of legs 1–4 armed with 9, 13, 8, and 8 setae, respectively, 1 seta (originally outer seta of basis) positioned on proximal outer margin. Endopods of legs 1–4 armed with 7, 8, 8, and 6 setae, respectively. All setae small and naked, except original inner distal seta on basis on proximal inner margin of leg 1 endopod broadened. Leg 4 smaller than anterior legs. Leg 5 absent.

Male. Unknown.

Remarks. The new species shares the same species of host with Adrodelphys tectifera gen. et sp. nov. (described below) from the same locality.

Figures

FIGURE 382. Unimeria longipedata gen. et sp. nov., female. A, habitus, right; B, urosome, dorsal; C, caudal ramus, dorsal; D, rostrum; E, antennule; F, antenna; G, labrum; H, mandible; I, maxillule; J, maxilla; K, leg 1; L, leg 2; M, leg 3; N, leg 4. Scale bars: A, 0.5 mm; B, 0.1 mm; C, H–J, 0.02 mm; D–G, K–N, 0.05 mm.