Enterocola pterophorus Chatton & Brément, 1909

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 : 198

Enterocola pterophorus Chatton & Brément, 1909

( Figs. 125 , 126 )

Material examined. 6 ♀♀ (MNHN-IU-2014-21541, 2 ♀♀ dissected) in Trẚdẚdemnum cereum (Giard, 1872); Glenan Is., Atlantic coast of France, Lafargue coll., date unknown .

Supplementary description of female. Body ( Fig. 125A, B ) inflated, unsegmented, slightly depressed, and curved dorsally. Body length 1.09 mm in largest specimen; maximum width 445 μm (across region of leg 2). Cepha- losome obscurely defined from trunk, much wider than long. Trunk narrowing posteriorly, with 3 pairs of dorsal tergal folds, 1 pair each on second to fourth pedigerous somites; left and right tergal folds separated from each other on second pedigerous somite, but close to each other on third and fourth pedigerous somites. Ventral surface of trunk lacking interpodal protrusions between left and right legs. Genitoabdomen not defined from but distinctly narrower than trunk, lacking any trace of articulation; dorsal anal prominence distinct. Caudal rami ( Fig. 125C ) about 2.0 times longer than wide (67×33 μm), unarmed, tapering towards blunt apex. Egg sac ( Fig. 125D ) curved, 505×240 μm; eggs arranged in 3 or 4 rows, each egg about 160 μm in diameter.

Rostrum absent. Antennule ( Fig. 125E ) 42×27 μm, strongly tapering, with convex anterior margin and straight posterior margin, armed distally with 5 (occasionally 4) setae of subequal lengths. Antenna ( Fig. 125F ) flattened, indistinctly 2-segmented, 119×57 μm; proximal segment unarmed; distal segment as long as proximal segment, armed with 6 small setae, and ornamented with fine spinules on concave surface; lengths of setae I-VI (medial to lateral setae) 15, 12, 12, 20, 21, and 34 μm, respectively; setae 1-3 curved and stiff.

Labrum ( Fig. 125G ) rhomboidal, bearing pair of palps and patch of spinules near base of palps; palp densely spinulose, club-shaped, gradually thickening distally. Mandible ( Fig. 125G ) tapering, densely spinulose, slightly shorter than labral palp. Maxillule ( Fig. 125H, I ) 2-segmented; endite of proximal segment (precoxa) with 1 slender, spinulose seta and more than 20 thin setules; palm-shaped distal segment (palp) with 5 spinulose setae on distal margin and 1 small, naked, setiform process on lateral margin. Maxilla ( Fig. 125J ) 2-segmented; proximal segment (syncoxa) with mediodistal endite bearing thick, spinulose, spiniform element; distal segment with tapering distal part, with thick subterminal spine bearing several rows of spinules along medial margin, and with 1 small seta proximally on posterior surface. Maxilliped absent.

Legs 1-4 each with unsegmented protopod and rami ( Fig. 126 A-C); protopods unarmed. Exopod of leg 3 ( Fig. 126B ) elongate, longer than endopod, and acutely pointed. Exopods of legs 1, 2, and 3 distinctly shorter than endopod, tipped with small, claw-like process. Endopods of legs 1-4 50×27, 58×29, 54×27, and 46×26 μm, respectively. Lengths of laterodistal and mediodistal setae on endopods: 52 and 45, 45 and 41, 48 and 45, and 50 and 41 μm in legs 1-4, respectively.

Leg 5 ( Fig. 125K ) much wider than long (120×205 μm) and unarmed.

Male. Unknown.

Remarks. bnterçcçla pterçphçrus was redescribed and illustrated in detail by Illg & Dudley (1980) based on specimens from a variety of different ascidian hosts. Of the copepods they examined, those associated with aẚdemnum fulgens (Milne Edwards, 1841) from the Mediterranean Sea and Trẚdẚdemnum tenerum (Verrill, 1871) from the North East Atlantic displayed the characteristic form and setation of the antennule and antenna, and this was shared with our specimens associated with Trẚdẚdemnum cereum from the North East Atlantic. In this material the antennule tapers and is armed with 3 to 5 small setae distally, and the antenna is armed with 6 small setae (mediodistal 3 strongly curved). In addition to these features, our specimens and those of Illg & Dudley’s share an unsegmented genitoabdomen and the absence of the ventral interpodal protrusions between left and right legs. On the basis of the evidence provided by the combination of all these characters, we identified our specimens as b. pterçphçrus.

Figures

FIG. 125. bnterçcçla pterçphçrus Chatton & Brément, 1909, female. A, habitus, dorsal; B, habitus, right; C, caudal rami; D, egg sac; E, antennule; F, antenna; G, labrum and mandibles; H, precoxa of maxillule; I, palp of maxillule; J, maxilla; K, leg 5. Scale bars: A, B, D, 0.1 mm; C, E-J, 0.02 mm; K, 0.05 mm.

FIG. 126. bnterçcçla pterçphçrus Chatton & Brément, 1909, female. A, leg 1; B, leg 3; C, leg 4. Scale bars: 0.02 mm.