Haplostomides bermudensis, 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 : 136-138

Haplostomides bermudensis sp. nov.

( Fig. 89 )

Type material. Holotype ♀ (MNHN-IU-2018-1989), 4 ♀♀ paratypes (MNHN-IU-2018-1990), and 2 ♀♀ para- types (dissected, MNHN-IU-2014-17381) from mçlyclẚnum cçnstellatum Savigny, 1816 (MNHN-IT-2008-6981 = MNHN A1 / POL.B/3); St David’s I., Bermuda, 1970.

Etymology. The new species is named after its type locality.

Description of female. Body ( Fig. 89A ) similar to e. sẚmẚlẚs sp. nov. in form, unsegmented, curved dorsally, and narrowing anteriorly. Body length 4.20 mm; maximum width 0.97 mm in posterior quarter. Intervals between first to fourth legs 0.76, 0.98, and 1.21 mm, respectively. Genitoabdomen short, not defined from metasome. Caudal ramus ( Fig. 89B ) slightly wider than long (25×29 μm), indistinctly defined from genitoabdomen, armed with 1 distal spine and 2 setae (1 at proximal third of outer margin and 1 dorsal, subdistally); distal spine longer than wide (11×8 μm). Egg sac ( Fig. 89D ) 3.26× 0.29 mm, containing 3 or 4 rows of eggs; each egg about 170 μm in diameter.

Rostrum ( Fig. 89C, E ) small, much wider than long, ornamented with minute spinules subdistally and 4 minute sensilla proximally. Antennule ( Fig. 89F ) 4-segmented; armature formula 3, 1, 2, and 10+2 aesthetascs; terminal segment subdivided by partial suture in middle of posterior side into parts bearing 4+aesthetasc and 6+aesthetasc. Antenna ( Fig. 89G ) 2-segmented; proximal segment (coxobasis) unarmed; distal segment (endopod) with 2 larger distal and 2 very small subdistal spines; all spines articulated at base.

Labrum ( Fig. 89H ) weak, flexible, unornamented, with broadly convex posterior margin. Mandible ( Fig. 89I ) digitiform, tapering distally, with slight constriction distally and 2 small setae subapically. Maxillule ( Fig. 89J ) incompletely 2-segmented; proximal segment (precoxa) with 3 setae (distalmost rudimentary); distal segment (palp) roughly quadrate, with 5 setae (4 outer and 1 distal), distal seta shorter than other 4. Maxilla ( Fig. 89K ) as broad lobe bearing 1 apical and 1 subapical seta. Maxilliped ( Fig. 89L ) 4-segmented; first segment broad, unarmed; second segment with 2 small setae; third and fourth segments small, unarmed; terminal claw small, conical, half as long as fourth segment.

Legs 1-4 biramous, consisting of protopod, exopod, and small endopod ( Fig. 89 M-O). Both rami not articulated from protopod; protopods with outer seta. Exopods of legs 1, 3, and 4 each armed with 1 seta and 2 spines ( Fig. 89M, O ). Exopod of leg 2 ( Fig. 89N ) armed with 1 seta and 3 spines. Endopod rather distinct, bearing 1 or 2 sensilla. Endopods of legs 3 and 4 shorter but broader than in legs 1 and 2.

Leg 5 represented by 2 minute setae. Leg 6 represented by 1 spine and 1 spiniform process in genital area, accompanied by 5 internal, tooth-like elements.

Male. Unknown.

Remarks. In the genus eaplçstçmẚdes the number of armature elements on the exopod of leg 1 is more than or the same as that of leg 2. The exopods of legs 1-4 of eaplçstçmẚdes bermudensẚs sp. nov. are armed with 3, 4, 3, and 3 armature elements, respectively, which is an unusual combination of armature elements that serves to characterize the new species. The maxillule of e. bermudensẚs sp. nov. is armed with 3 setae on the proximal segment and 5 setae on the distal segment. This maxillulary setation is shared only with e. brementẚ Chatton & Harant, 1924, but further comparison between e. brementẚ and the new species is unnecessary because of the different armature patterns in legs 1-4 of e. brementẚ (5, 4, 3, and 3 according to Ooishi (2008a)).

Figures

FIG. 89. eaplçstçmẚdes bermudensẚs sp. nov., female. A, habitus, right; B, caudal rami, dorsal; C, cephalic appendages, right; D, egg sac; E, rostrum; F, antennule; G, antenna; H, labrum; I, mandible; J, maxillule; K, maxilla; L, maxilliped; M, leg 1; N, leg 2; O, leg 3. Scale bars: A, D, 0.5 mm; B, E-O, 0.02 mm; C, 0.05 mm.