Campodelphysbullatus, 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 : 591-595

Campodelphysbullatus gen. etsp. nov.

( Figs. 398 , 399 )

Type material. Holotype ♀ (dissected and mounted on a slide, MNHN-IU-2014-21431 ) from Aplidium lobatum Savigny, 1816 (MNHN-IT-2008-490 = MNHNA1/APL. B/499), Djibouti, Red Sea, depth 3 m, Monniot coll., 1995.

Etymology. The specific namerefers tothe presence of the paired bullae on the ventral surface of the anal somite.

Descriptionoffemale. Body ( Fig. 398A ) elongate, cylindrical, curved dorsally: bodylength 2.06 mm. Prosome unsegmented, narrowing anteriorly and posteriorly from maximum width in mid-region (415 μm wide); cephalosome not demarcated from metasomal region, bearing paired tubercles ( Fig. 398E ) on ventral surface located lateral to oral region. Anterior region of prosome, from rostrum to leg 4, occupying about 30% of prosome length; region posterior to insertion of leg 4 forming brood pouch. Free urosome ( Fig. 398B ) small, consistingof genitalsomiteand 4 abdominalsomites, 137 μm long, curved ventrally. Anal somite ( Fig. 398C ) with paired trilobate swellings (bullae) on ventral surface ( Fig. 398D ), surface of bullae ornamented with spinules, anal somitewithscattered setules. Caudal ramus ( Fig. 398C, D ) small, 18×14 μm, much shorter than anal somite, directed laterally: armed with 6 naked setae and ornamented with scattered setules.

Rostrum ( Fig. 398F ) 43×39 μm, tapering towards rounded distal margin, surface covered with setules. Antennule ( Fig. 398G ) short (about 52 μmlong), strongly tapering, incompletely 5-segmented; first segment with 2 setae; setae on other segments not distinguishable from setules. Antenna ( Fig. 398H ) stout, 3-segmentedwith short coxa; basis as long as wide, unarmed, broadened proximally; unsegmented endopod about 1.8 times longer than wide (25×14 μ); armed with 4 setae (1 in middle, 1 subdistal, and 2 distal) plusterminal claw 0.7 times as long as endopod.

Labrum missing. Mandible ( Fig. 398I ) with coxal gnathobase bearing pectinate medial margin; palp consistingof well-defined basis, exopod and endopod; armedwith 1 setaon basis, 4 pinnate setaeon exopod, 1 broad, naked seta on first endopodal segment and 4 setae on second. Maxillule ( Fig. 398J ) represented by lobe bearing 6 subequal, pinnate setae. Maxilla ( Fig. 398K ) unsegmented, armed with 6 setae (3 medial and 3 on distal margin). Maxilliped ( Fig. 398L ) small, obscurely 2-segmented, armed with 1 small seta on tip of second segment.

Legs 1–4 ( Fig. 399 A-D) broad, biramous, setulose, with 2-segmented rami and unsegmented or indistinctly 2-segmented protopod; coxa lacking inner seta. Outer seta on basis lacking in leg 1, but present in legs 2–4. Basis of leg 1 bearing small inner distal seta. First exopodal segment of legs 1–4 bearing broad, bifurcate process at outer distalcorner (outer branch of each process shorter and tipped with 1 to 4 small denticles). All setae on legs 1–4 short. Inner setaon first endopodal segment of legs 1–4 weakly pinnate; all other setae naked and usually blunt. Armature formula for legs 1–4 as follows:

	Protopod	Exopod	Endopod
Leg 1	0-1	1-0; 7	0-1; 6
Leg 2	1-0	1-1; 10	0-1; 7
Leg 3	1-0	1-1; 9	0-1; 8
Leg 4	1-0	1-1; 8	0-1; 7

Leg 5 ( Fig. 398B ) represented by 2 small setae on posteroventral margin of prosome, near base of free urosome.

Male. Unknown.

Remarks. Campodelphysbullatus gen. etsp. nov. shares some features with the type species C. hirsutus gen. et sp. nov. These are the only two species which possess 2-segmented endopods in all swimming legs. In the other three new species described below, the endopods of the swimming legs are typically 1-segmented, with the exception of the 2-segmented endopod of leg 1 only of C. stocki gen. etsp. nov. Campodelphysbullatus gen. etsp. nov. is readily distinguishable from the type species, C. hirsutus gen. et sp. nov., because it does not share any of the five outstanding features listed in the remarks section of thetype species.

Figures

FIGURE 398. Campodelphys bullatus sp. nov., female. A, habitus, right; B, urosome, right; C, anal somite and caudal rami, dorsal; D, distal part of anal somite, right; E, ventral tubercle of cephalosome; F, rostrum; G, antennule; H, antenna; I, mandible; J, maxillule; K, maxilla; L, maxilliped. Scale bars: A, 0.2 mm; B, 0.05 mm; C–H, 0.02 mm; I–L, 0.01 mm.

FIGURE 399. Campodelphys bullatus sp. nov., female. A, leg 1; B, leg 2; C, leg 3; D, leg 4. Scale bars: 0.02 mm.