Doropygus martiniquensis, 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 : 344-347

Doropygus martiniquensis sp. nov.

( Figs. 228 , 229 )

Typematerial. Holotype (intact ♀, MNHN-IU-2017- 2080 ) , paratypes (7 intact ♀♀, MNHN-IU-2014-21316), and dissected paratype (♀, figured) from Pyura vannamei Monniot C., 1994 , MADIBENTHOS Stn. AB 189, SE Pointe Caracoli, Martinique (14°44.1 Ń, 60°50.8 Ẃ), depth 16 m, MNHN coll., 18 September 2016.

Additionalmaterial. 6 ♀♀ (MNHN-IU-2017-2078) from P. vannamei , Martinique (14°38 Ń, 60°51.2 Ẃ), MADIBENTHOSStnAR188,depth 5-14m, 17September 2016; 2 ♀♀ (MNHN-IU-2017-2081) from P. vannamei , Martinique (14°38 Ń, 60°51.2 Ẃ), MADIBENTHOS Stn AR 188, depth 5-14 m, 17 September 2016.

Etymology. The specific name is derived from the name of the type locality, Martinique.

Descriptionoffemale. Body ( Fig. 228A ) narrow, laterally compressed, 2.73 mmlong; prosome 2.25 mm long. Dorsalcephalic shield clearly defined. Pedigerous somites not articulated but delimited by constrictions. Fourth pedigerous somite forming conical brood pouch with blunt posterior margin, 1.03×0.69 mm in lateral view, occupying about 46% of prosomal length. Fifth pedigerous somite fused with brood pouch. Free urosome 5-segmented: abdominal somites becoming shorter posteriorly. Caudal rami ( Fig. 228B ) divergent, widely separated from each other; each ramus tapering and only partially articulated from anal somite (on outer side), about 3.2 timeslongerthan wide (205×64 μm) and twice as long as anal somite: armed with 6 small setae; all setae shorter than width of ramus at base; outer proximal and dorsal setae characteristically positioned together at same level (40% length of ramus).

Rostrum ( Fig. 228C ) weak, spatulate, nearly as long as wide. Antennule ( Fig. 228D ) 300 μm long, 9- segmented, gradually narrowing distally; armature formula 3, 17, 6, 4+aesthetasc, 4, 3+aesthetasc, 2, 2+aesthetasc, and 7+aesthetasc; 2 pinnate setae on first segment, 3 on second, and 1 each on fifth and sixth; first segment ornamented with minute spinules on anterior margin. Antenna ( Fig. 228E ) with unarmed coxa; basis with small knob at outer distal corner (representing exopod), tipped with 2 small setae, plus 1 small seta on distal margin; first endopodal segment inflated outwards, unarmed; compound distal endopodal segment about 3.3 timeslongerthan wide (82×25 μm); armedwith 10 small setae plus small terminal claw, less than half as long as segment.

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

Labrum ( Fig. 228F ) with linear, setulose posterior marginand smooth posteromedian lobe. Mandible ( Fig. 228G ) with 5 teeth and 1 smallseta on coxal gnathobase; basis with 1 seta distally on medial margin; exopod unsegmented with 5 equally long setae; endopod incompletely articulated from basis, armed with 4 and 9 setae on first and second segments, respectively, and ornamented with patch of fine spinules at outer distal corner of each segment; second distal outer seta on second endopodal segment markedly larger than other setae on endopod. Paragnath ( Fig. 228H ) as small lobe bearing semicircular lobule outer distally; denselysetulose on medial margin. Maxillule ( Fig. 228I ) with 9 setae and proximal tuft of setules on arthrite, 1 moderately broad seta on coxal endite, 2 unequal setae on epipodite, 3 setae (increasingly in length from proximal to distal) on medial margin of basis; exopod with 3 setae, outermost seta about twice as long as inner 2; endopod also with 3 setae distally, outermost seta slightly shorter than inner 2. Maxilla ( Fig. 228J ) 5-segmented; syncoxa with 9 setae arranged as 3, 1, 2, and 3; basiswith 3 setae; endopodwith 1, 1, and 3 setae on first to third segments, respectively; one of setae on third endopodal segment naked and wrinkled. Maxilliped ( Fig. 229A ) incompletely 2-segmented; articulation confined to medial half of limb; first segment with 8 setae; second segment with 2 equal, large setae distally.

Leg 1 ( Fig. 229B ) biramous with 3-segmented rami. Outersetaonbasisbroadproximallyand flagellatedistally. Inner distal spine on basis 53 μm long, extending slightly beyond distal border of second endopodal segment. Legs 2–4 ( Fig. 229 C-E) biramous, with 3-segmented exopods and 2-segmented endopods; exopod nearly equal in length to endopod in leg 2, slightly longer in leg 3, and distinctly longer in leg 4. Inner coxal seta well-developed, about 1.5 times longer than endopod and extending about to distal end of endopod. Outer seta on basis small. Legs 3 and 4 lacking inner seta on first exopodal segment. Outer setae on first and second exopodal segments and all setae on third exopodal segment of legs 2–4 naked. Armature formula for legs 1–4 as follows:

Leg 5 ( Fig. 229F ) 2-segmented: protopod widerthan long, not defined from brood pouch, with small naked seta at outer distal corner and patch of spinules on inner side; free exopodal segment slender, about 4 times longer than wide (115×29 μm) with nearly parallel margins; ornamented with 4 rows of spinules on dorsomedial surface; armed with 2 unequal naked setae distally, outer seta more than 3 times longer than inner.

Male. Unknown.

Remarks. The morphology of the cephalic appendages and legs of this new species are very similar to those of the two new species described below. These three species are compared below, in the remarks section of D. rotundus sp. nov. and their distinguishing character states are summarised in Table 8 .

Figures

FIGURE 228. Doropygus martiniquensis sp. nov., female. A, habitus, right; B, anal somite and caudal rami, ventral; C, rostrum; D, antennule; E, antenna; F, labrum; G, mandible; H, paragnath; I, maxillule; J, maxilla. Scale bars: A, 0.5 mm; B, 0.1 mm; C–G, 0.05 mm; H–J, 0.02 mm.

FIGURE 229. Doropygus martiniquensis sp. nov., female. A, maxilliped; B, leg 1; C, leg 2; D, leg 3; E, leg 4; F, leg 5. Scale bars: 0.05 mm.