Monnioticopa manadoensis, Kim & Boxshall, 2021

Kim, Il-Hoi & Boxshall, Geoff A., 2021, Copepods (Cyclopoida) associated with ascidian hosts: Ascidicolidae, Buproridae, Botryllophilidae, and Enteropsidae, with descriptions of 84 new species, Zootaxa 1, pp. 1-286 : 259-262

Monnioticopa manadoensis gen. et sp. nov.

( Figs. 171 , 172 )

Type material. Holotype ♀ (MNHN-IU-2014-21578, dissected and mounted on a slide) from budẚstçma ẚncrustatum Monniot F. & Monniot C., 1996 (MNHN-IT-2008-4103 = MNHN A3 / EUD/76 ); N. Sulawesi, Indonesia, 13MI W of Murex Resort, W of Manado town OCDN 1283 -F, Site MANADO 6 (01°23.56’N, 124°32.62’E), depth 43 m, CRRF coll., 10 May 1993.

Etymology. The type locality is the source of the name of the new species.

Description of female. Body ( Fig. 171A, B ) eruciform, with soft exoskeleton; body length 1.29 mm; maximum width 382 μm (across second pedigerous somite). Cephalosome short, slightly narrower than first pedigerous somite. Trunk obscurely segmented; first to fourth pedigerous somites defined from one another by lateral constrictions, bearing indistinct dorsal tergites. Genitoabdomen recurved dorsally, 4-segmented; anal somite ( Fig. 171C ) ornamented with 4 transverse rows of minute spinules on lateral surfaces; anal prominence distinct. Caudal rami ( Fig. 171C ) rectangular, broad, slightly longer than anal somite, about 1.8 times longer than wide (80×44 μm), or- namented with numerous, minute spinules; armed with 1 large naked seta (38 μm long) positioned at 66% of ramus length plus 3 granule-like vestigial setae subdistally on dorsal surface.

Rostrum ( Fig. 171D ) small, sub-rectangular, with rounded posterolateral corners. Antennule ( Fig. 171E ) small, 87 μm long, 3-segmented, articulation between second and third segments incomplete; armed with 4, 1, and 8 small setae on first to third segments, respectively. Antenna ( Fig. 172F ) about 70 μm long, digitiform, unarmed, 3-segmented with right angle curve between first and second segments; third segment longest, 33 μm long; second and third segments ornamented with scattered spinules.

Labrum semicircular, unarmed and unornamented. Mandible ( Fig. 171G ) represented by large, powerful claw. Maxillule ( Fig. 171H ) bilobed; larger inner lobe with 1 broad, spinulose seta apically; outer lobe shorter and narrower than inner, digitiform, tipped with 1 slender, naked seta. Maxilla ( Fig. 171I ) bilobate, with broad basal part; inner lobe (endite of syncoxa) twice as long as outer lobe, armed with 1 spinulose seta apically; outer lobe armed with 1 small seta at mid-length plus 2 unequal distal setae, both characteristically sigmoid in shape. Maxilliped absent.

Legs 1-4 each consisting of 2-segmented protopod and unsegmented rami ( Fig. 171J, K ); basis with small outer seta. Exopods much smaller than endopods, tipped with 1 small claw and 1 small, circular lamella; exopod of leg 3 armed additionally with 1 large spine on lateral margin ( Fig. 171K ). Endopods 59×29, 86×36, 91×38, and 89×38 μm, respectively, in legs 1-4. Lengths of laterodistal and mediodistal setae on endopods 97 and 83, 105 and 89, 108 and 86, and 109 and 85 μm, respectively, in legs 1-4.

Leg 5 ( Fig. 171L ) lamellate, nearly circular, as long as wide (172×176 μm), with 2 small setae; distance be- tween setae 118 μm.

Copepodid juvenile. Body ( Fig. 172A ) curved dorsally, consisting of cephalosome, 4-segmented trunk, and indistinctly 3-segmented genitoabdomen. First to fourth pedigerous somites each with faint tergite; fifth pedigerous somite not differentiated. Anal somite ornamented as in adult female. Caudal ramus 2.20 times longer than wide, armed as in adult female.

Rostrum ( Fig. 172B ) semicircular. Antennule 2-segmented, armed with 4 setae on proximal segment and 11 setae on distal segment. Antenna 3-segmented, curved as in adult female, but not ornamented. Labrum ( Fig. 172B ) semicircular, smooth. Mandible, maxillule, and maxilla as for adult female. Maxilliped absent.

Legs 1-4 biramous with 2-segmented protopods; basis bearing 1 small seta on outer margin. Leg 1 ( Fig. 172C ) exopod 2-segmented; proximal segment of exopod with projecting laterodistal corner bearing pointed distal process and 1 thick spine; distal segment inserted into medial margin of proximal segment, armed with 2 thick spines distally (medial spine twice as long as lateral); endopodal segment 1.7 times longer than wide, 2 distal setae shorter than segment. Leg 2 same as leg 1. Leg 3 ( Fig. 172D ) exopod 2-segmented; proximal segment of exopod armed with large spine at laterodistal corner; distal segment armed as in legs 1 and 2, but longer; endopodal segment twice as long as wide, armed as in legs 1 and 2. Leg 4 ( Fig. 172E ) exopod unsegmented, armed with 3 small spines, 1 on lateral margin, 1 subdistal, and 1 distal; distal setae on endopodal segment short, less than half length of segment. Leg 5 not differentiated.

Male. Unknown.

Remarks. Mçnnẚçtẚcçpa manadçensẚs gen. et sp. nov. is distinguishable from its congeners by the possession of the 2 specialized (sigmoid in shape) setae located distally on the outer lobe of the maxilla. In addition, in M. manadçensẚs gen. et sp. nov. the first segment of the antennule is armed with 4 setae and the third segment of the antenna is the longest segment. These features of the antennule and antenna are shared only with M. fẚrma gen. et sp. nov. However, these two species are easy to separate because in M. fẚrma gen. et sp. nov. the antenna is straight, the first to fourth pedigerous somites each bear a well-developed dorsal tergite, the inner lobe of the maxillule is unarmed, and the coxae of legs 1-4 each bear a large mediodistal projection.

Figures

FIG. 171. Mçnnẚçtẚcçpa manadçensẚs gen. et sp. nov., female. A, habitus, dorsal; B, habitus, right; C, anal somite and caudal rami, dorsal; D, rostrum; E, antennule; F, antenna; G, mandible; H, maxillule; I, maxilla; J, leg 1; K, leg 2; L, leg 5. Scale bars: A, B, 0.1 mm; C-I, 0.02 mm; J-L, 0.05 mm.

FIG. 172. Mçnnẚçtẚcçpa manadçensẚs gen. et sp. nov., copepod juvenile.A, habitus, right; B, cephalic appendages; C, leg 1; D, leg 3; E, leg 4. Scale bars: A, 0.1 mm; B-E, 0.02 mm.