Notodelphys aurantiaca Stock, 1970

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 : 23-26

Notodelphys aurantiaca Stock, 1970

( Figs. 10 , 11 )

Material examined. 2 ♀♀, 2 ♂♂ (MNHN-IU-2018- 1761) and 1 dissected ♀ from Ascidia curvata (Traustedt, 1882) , Guadeloupe, No. 18; 1 ♀ (MNHN-IU-2018-1762) and 1 dissected ♀ (figured) from A. curvata, Riviere salee, Guadeloupe, February 1985.

Supplementary description of female. Body ( Fig. 10A ) 4.56 mm long. Cephalosome widerthan long. Fifth pedigerous somite completely incorporated into brood pouch. Freeurosome ( Fig. 10B ) 5-segmented: genital somite 175× 320 μm, shorter than 4 free abdominal somites 233×313, 240×302, 233×265, and 225×233 μm, respectively, each wider than long. Anal somite ornamented with fine spinules on posteroventral margin and few setules near posterolateral corner. Caudal ramus ( Fig. 10C ) gradually narrowing distally, denselysetulose on both inner and outer margins; outer lateral seta located subdistally at 78% of ramus length. Rostrum ( Fig. 10D ) elongate, 184×100 μm, with truncated apex. Antennule 505 μm long, 10-segmented ( Fig. 10E ), segmental fusion pattern as follows: I-II, III-V, VI-XI, XII-XIV, XV-XVI, XVII-XX, XXI-XXIII, XXIV, XXV, XXVI-XXVIII; armatureformula 3, 5, 12, 6, 4+aesthetasc, 7, 3+aesthetasc, 2, 2+aesthetasc, and 7+aesthetasc; setae on proximal segments mostly pinnate (as figured). Antenna ( Fig. 10F ) rather stout with short unarmed coxa; basis with 2 equally large pinnate setae representing exopod; first endopodal segment with 1 subdistal seta on inner margin; compound distal endopodal segment 133×44 μm, 3.2 times as long as wide, with 9 setae (arranged as 1, 1, 3, 1, and 3) plus strong terminal claw; 3 distal setae on second endopodal segment naked and blunt at tip.

Labrum ( Fig. 10G ) with denticles on middle of posterior margin and setules on produced posterolateral corners. Mandible ( Fig. 10H ) with 4 teeth on coxal gnathobase; basis with 1 setaon inner margin; exopod with 5 setae, distal seta much larger than others; endopod with 4 setae on first segment and 9 setae on second. Maxillule ( Fig. 10I ) with 10 setae on precoxal arthrite, 1 seta on coxal endite, 2 unequal setae on coxal epipodite; basis with 1 short proximal and 2 longer distal setae on inner margin; exopod indistinctly 2-segmented, with 4 setaeon distal segment; endopod distinctly 2-segmented, with 1 seta on proximal segment and 4 setae on distal segment, outermost seta markedly shorter than other 3. Maxilla ( Fig. 10J ) consistingof syncoxa, basis, and 3-segmented endopod; syncoxa with 4, 1, 2, and 3 setae on first to fourth endites, respectively; basis carrying strong claw with fine spinulesalongconcavemargin, plus 2 setae; endopodwith 1, 1, and 4 setae on first to third segments, respectively, one of setae on thirdsegment minute. Maxilliped ( Fig. 11A ) 3-segmented; armatureformula 9, 1, and 3.

Legs 1–4 with 3-segmented rami. Leg 1 ( Fig. 11B ) with straight inner distal spine on basis; first endopodal segment about 1.5 times as long as wide, longer than distal 2 segments combined. Leg 2 ( Fig. 11C ) identical to leg 3 in armature formula. Leg 4 ( Fig. 10D ) with inner spine (rather than seta) on coxa; inner seta on first exopodal segment small, as long as outer seta on same segment. Armature formula for legs 1–4 as follows:

	Coxa	Basis	Exopod	Endopod
Leg 1	0-1	1-I	I-0; I-1; III, 5	0-1; 0-1; 1, 2, 3
Legs 2 & 30-1	30-1	1-0	1-1; 1-1; 3, 1, 5	0-1; 0-1; 1, 2, 3
Leg 4	0-I	1-0	1-1; 101; 2, 1, 5	0-1; 0-1; 1, 2, 2

Leg 5 ( Fig. 11E ) small, located on posteroventral surfaceof brood pouch, consisting of incorporated protopod and free exopod. Protopod with 1 seta tipped on elongate lateral process. Exopodal segment 19×23 μm, wider than long, about half as long as lateral process of protopod, and armed with 1 naked seta and 1 rudimentary seta. Leg 6 absent.

Remarks. Our specimens from Guadeloupe are identified as N. aurantiaca because the first endopodal segment of leg 1 is elongated, about 1.5 times longer than wide, the lateral process of the protopod of leg 5 is elongate (distinctly longerthan wide), and the exopod of leg 5 is sub-rectangular. These distinctive character states are all typical of N. aurantiaca . Stock’s (1970) material was collected from Ascidia interrupta Heller, 1878 at Curaçao in the Caribbean Sea.

Figures

FIGURE 10. Notodelphys aurantiaca Stock, 1967, female. A, habitus, dorsal; B, urosome, ventral; C, left caudal ramus, dorsal; D, rostrum; E, antennule; F, antenna; G, labrum; H, mandible; I, maxillule; J, maxilla. Scale bars: A, 1 mm; B, 0.2 mm; C, 0.1 mm; D–J, 0.05 mm.

FIGURE 11. Notodelphys aurantiaca Stock, 1967, female. A, maxilliped; B, leg 1; C, leg 2; D, leg 4; E, left leg 5, ventral. Scale bars: A, 0.05 mm; B–D, 0.1 mm; E, 0.02 mm.