Copepods (Cyclopoida) associated with ascidian hosts: Ascidicolidae, Buproridae, Botryllophilidae, and Enteropsidae, with descriptions of 84 new species Author Kim, Il-Hoi m@gwnu Author Boxshall, Geoff A. m@gwnu text Zootaxa 2021 1 1 286 journal article 10.11646/zootaxa.4978.1.1 1175-5326 4820443 9C7C1723-73EB-4FBE-A47A-54627DEB8F93 Enterocola fulgens van Beneden, 1860 ( Figs. 127 , 128 ) Material examined. 9 ♀♀ (MNHN-IU-2014-21542, 2 ♀♀ dissected) from mçlyclẚnum aurantẚum Milne Edwards, 1841; Saint-Vaast-la-Hougue, Atlantic coast of France , Monniot coll., date unknown . Supplementary description of female. Body ( Fig. 127 A-C) eruciform, cylindrical, consisting of cephalosome, trunk and genitoabdomen. Body length 1.36 mm in dissected specimen; mean body length 1.27 mm ( 0.98-1.45 mm ), based on 7 specimens : maximum width 352 μm (across second pedigerous somite). Cephalosome 1.25 times wider than long, distinctly narrower than trunk, and well-defined from first pedigerous somite. Trunk consisting of first to fifth pedigerous somites, unsegmented or indistinctly segmented; first to fourth pedigerous somites each bearing dorsal tergite and paired ventral interpodal protrusions, these protrusions weak in first and second pedigerous somites, but prominent in third and fourth; in young adult ( Fig. 127C ) dorsal tergites usually incomplete, forming dorsolateral tergal folds. Genitoabdomen ( Fig. 127D ) 4-segmented, consisting of genital double-somite and 3 abdominal somites, ornamented with numerous minute spinules on all surfaces; articulations between somites distinct on ventral surface but indistinct dorsally; anal prominence large. Caudal rami ( Fig. 127E ) unarmed, about 2.5 times longer than wide (136×54 μm), slightly narrowing distally, about twice as long as anal somite, with rounded distal margin; covered with numerous minute spinules. Rostrum absent. Antennule ( Fig. 127G ) distinctly 3-segmented, consisting of expanded first segment and small distal segments; first segment much wider than long (45×61 μm), with straight, sclerotized anterior margin, strongly protruding posterior margin, armed with 1 small seta distally and ornamented with 2-5 setiform spinules near base of second segment; second segment wider than long (5×8 μm) armed with 1 small seta at posterodistal corner; third segment slightly longer than wide (7×5 μm), armed with 1 seta and 1 setiform process distally. Antenna ( Fig. 127H ) about 135×68 μm, 2-segmented, but suture line between segments vestigial; proximal segment unarmed, but ornamented with spinules on convex surface; distal segment distinctly longer than proximal segment, armed with 6 small setae and ornamented with scattered spinules on convex surface; lengths of setae I-VI (medial to lateral) 18, 32, 25, 11, 27, and 13 μm, respectively; setae IV and VI markedly smaller than other 4 setae. Labrum ( Fig. 127I ) with cylindrical, spinulose palp and 2 patches of spinules on each side; posterior margin projecting, with truncate apex. Mandible ( Fig. 127I ) spinulose, shorter and more slender than labral palp. Maxillule consisting of precoxa ( Fig. 127J ) and palp ( Fig. 127K ): precoxa ( Fig. 127J ) with bluntly bifurcate tip; endite tipped with 1 spinulose spine and about 10 short spinules: palp ( Fig. 127K ) with 5 stout spinulose spines on distal margin and 1 naked, attenuated spine on lateral margin. Maxilla ( Fig. 127L ) 2-segmented; proximal segment (syncoxa) with mediodistal endite extending to distally spinulose large process; distal segment with 2 blunt distal projections (shorter anterior and longer posterior), and 1 small, blunt seta proximally on posterior surface. Maxilliped absent. FIG. 127. bnterçcçla fulgens van Beneden, 1860 , female. A, habitus, dorsal; B, habitus, ventral; C, habitus of young adult, dorsal; D, genitoabdomen, dorsal; E, caudal rami, dorsal; F, egg sac; G, antennule, with inset showing detail of distal segments; H, antenna; I, labrum and mandibles; J, precoxa of maxillule; K, palp of maxillule; L, maxilla. Scale bars: A-C, F, 0.2 mm; D, 0.1 mm; E, 0.05 mm; G-L, 0.02 mm. FIG. 128. bnterçcçla fulgens van Beneden, 1860 , female. A, leg 1; B, leg 3; C, leg 5. Scale bars: 0.05 mm. Legs 1-4 each consisting of 2-segmented protopod and 1-segmented rami; protopods unarmed, but ornamented with rows of minute spines. Exopods shorter than endopods ( Fig. 128A ); exopod of leg 3 acute, spiniform ( Fig. 128B ). Endopods 68×33, 89×38, 92×39, and 82×38 μm, respectively, in legs 1-4; each endopod armed with 2 setae distally. Two distal setae on endopods characteristically equal in length, 0.6-0.7 times as long as endopodal segments; lengths of endopodal setae 48, 59, 55, and 55 μm, respectively, in legs 1-4. Leg 5 ( Fig. 128C ) wider than long (167×196 μm), armed with 2 small setae on distal margin separated by dis- tance of 136 μm. Male . See Ooishi (2007b) . Remarks. Ooishi (2007b) redescribed this species in detail on the basis of specimens collected from the ascidian mçlyclẚnum aurantẚum at Roscoff. Our examined copepod specimens were associated with the same ascidian host from a nearby geographical locality. bnterçcçla fulgens seems to be a distinctive species due to its characteristic antennule which is distinctly 3-segmented, with the first segment inflated and 2 small distal segments. Nevertheless, we found some differences in details between Ooishi’s and our material, as follows: (1) the caudal ramus is 1.6 times longer than wide in Ooishi’s material, compared to 2.5 times longer than wide in our material; (2) the antennule is armed with 2, 1, and 3 setae on the first to third segments, compared to the setation 1, 1, and 1 in our material; (3) the setae on the antenna of Ooishi’s material are shorter than those of our material; (4) the ventral interpodal protrusions on the first to fourth pedigerous somites of Ooishi’s material are obscure, but distinct in our material; and (5) the 2 distal setae on the endopods of legs 1-4 of Ooishi’s material are unequal in length, compared to the equal lengths in our material. On the evidence available, we interpret these differences as due to infraspecific variation, at least in part because some of this variability is shown in the illustrations of Illg & Dudley (1980) . Illg & Dudley (1980) recorded variability in the setation of the antenna, noting that either 5 or 6 setae were present. In the 5-setae condition in Illg & Dudley’s material, the smallest apical seta (seta IV), which is the most likely to be overlooked, was missing. This variability could not be confirmed in our study or by Ooishi (2007b) .