Enterocola tuberculatus, 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 : 219-221

publication ID	https://doi.org/ 10.11646/zootaxa.4978.1.1
publication LSID	lsid:zoobank.org:pub:9C7C1723-73EB-4FBE-A47A-54627DEB8F93
DOI	https://doi.org/10.5281/zenodo.5047149
persistent identifier	https://treatment.plazi.org/id/3729879B-FF3F-FF2B-FA93-FD7DD76D18AB
treatment provided by	Plazi
scientific name	Enterocola tuberculatus
status	sp. nov.

Treatment

Enterocola tuberculatus sp. nov.

( Figs. 142 View FIG , 143 View FIG )

Type material. Holotype ♀ (MNHN-IU-2014-21554) and 1 ♀ paratype (dissected, MNHN-IU-2014-21472) from mçlysyncratçn cerebellum Monniot F. & Monniot C., 2001 (MNHN-IT-2008-7078 = MNHN A2 About MNHN / POL/96 ); Papua New Guinea, CRCHO 262 , Brooker Ils. , Louisiades, Site Brooker CH (11°03.09’S, 152°28.62’E) depth 12 m, CRRF coll., 01 June 1998. GoogleMaps

Etymology. The specific name alludes to the presence of a large dorsal tubercle on the first pedigerous somite of the new species.

Description of female. Body ( Fig. 142 View FIG A-C) eruciform, curved dorsally; body length 760 μm, maximum width 244 μm (across cephalic shield). Cephalic shield with obscure posterior margin. First pedigerous somite with weak tergal folds posterolaterally, but with large mid-dorsal projection ( Fig. 142A View FIG ); second to fourth pedigerous somites each with pair of large, lamellate dorsolateral tergal folds and single, broad ventral interpodal protrusion between left and right legs. Genitoabdomen ( Fig. 142D View FIG ) short, unsegmented dorsally, but 4-segmented ventrally, with distinct anal prominence. Caudal rami elongate, unarmed, originating close to each other; each ramus ( Fig. 142D View FIG ) about 3.5 times longer than wide (102×29 μm), slightly broadened proximally, with rounded distal margin.

Rostrum absent. Antennule ( Fig. 142E View FIG ) unsegmented, more than twice as long as wide (approximately 39×18 μm), with rounded distal margin, nearly parallel anterior and posterior margins; armed with 5 small setae at antero- distal corner. Antenna ( Fig. 142F View FIG ) incompletely 2-segmented, 2.34 times longer than wide (103×44 μm); proximal segment unarmed; distal segment as long as, but narrower than, proximal segment, and ornamented with fine spinules on concave surface; armed with 5 setae, lengths of setae I-V 17, 12, 12, 17, and 25 μm; medial seta (seta I) spinulose and distinctly thicker than other 4 setae; setae II and III positioned close to each other.

Labrum destroyed; palp ( Fig. 142G View FIG ) spinulose, bulbous, markedly inflated in distal half. Mandible ( Fig. 142H View FIG ) spinulose, slender, much narrower than labral palp. Maxillule as usual for genus; distal sclerotized part of precoxa ( Fig. 142I View FIG ) weakly bilobed; endite of precoxa tipped with 1 spinulose spine and more than 10 stiff setules; palp ( Fig. 142K View FIG ) armed with 5 spines on distal margin and 1 naked seta on lateral margin. Maxilla ( Fig. 142L View FIG ) 2-segmented; proximal segment with unarticulated, spinulose mediodistal process; distal segment distally bifurcate, with 1 minute seta proximally on posterior surface. Maxilliped absent.

Legs 1-4 ( Fig. 142M View FIG ; 143 View FIG A-C) each consisting of incompletely 2-segmented protopod and unsegmented rami; protopods unarmed. Exopods of legs 1, 2, and 4 with pointed distal tip and minute cusp subdistally on lateral margin; exopod of leg 3 elongate ( Fig. 143B View FIG ) and thin distally. Endopods 51×35, 48×22, 55×27, and 48×20 μm, respec- tively, in legs 1-4. Enodpods of legs 3 and 4 with convex lateral margin. Lengths of laterodistal and mediodistal setae on endopods 68 and 49, 59 and 47, 65 and 52, and 68 and 59 μm, respectively, in legs 1-4. Laterodistal setae on endopods longer than endopodal segments, 1.39, 1.26, 1.25, and 1.15 times longer than mediodistal setae on legs 1-4, respectively. Leg 5 ( Fig. 143D View FIG ) unarmed, wider than long (98×167 μm).

Male. Unknown.

Remarks. The most conspicuous feature of b. tuberculatus sp. nov. is the presence of a large dorsal tubercle on the first pedigerous somite, which serves to differentiate the new species from its congeners. The presence of any dorsal tubercles or projections has been recorded in only three species: there is a tapering posterior projection on the cephalic shield in b. dẚcaudatus (see Marchenkov & Boxshall, 2005), there are 2 tubercles (one each on the second and third pedigerous somites) in b. quadrẚsetus sp. nov., and 2 tubercles (one each on the cephalosome and first pedigerous somite) in b. parvus sp. nov.

The caudal rami of b. tuberculatus sp. nov. are elongate, 3.2 times longer than wide. This is another potential diagnostic feature of the new species, because in other species of bnterçcçla the length/width ratio of the caudal rami seldom exceeds 3.0. The exceptions are b. bẚlamellatus Sars, 1921, b. dẚcaudatus, b. quadrẚsetus sp. nov., and b. rçbustus sp. nov. all of which have caudal rami with a length to width ratio of about 3. These four species are easily separated from b. tuberculatus sp. nov. by their lack of a dorsal tubercle on the first pedigerous somite.

The antenna of bK tuberculatus sp. nov. is armed with 5 setae. This feature is shared with some varieties of b. fulgens and by four other species, b. adnatus, b. latẚceps, b. parapterçphçrus, and b. mabulensẚs sp. nov. ( Table 6 View TABLE 6 ). All of these species also lack any dorsal tubercles or projections.