Haplostoma manadoense, 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 : 143

Haplostoma manadoense sp. nov.

( Fig. 92 )

Type material. Holotype ♀ (MNHN-IU-2018-1992), 3 ♀♀ paratypes (MNHN-IU-2018-1993), and 1 ♀ paratype (dissected, MNHN-IU-2014-17383) from budẚstçma sp.; Point called TG Torowitan, North tip of Sulawesi, Indonesia, OCDN 1431 -P, Site MANADO 25 (01°45.10’N, 124°58.87’E), depth 5 m, CRRF coll., 21 May 1993.

Etymology. The name of the type locality, Manado, is taken for the name of the new species.

Description of female. Body ( Fig. 92A ) eruciform, relatively slender, slightly curved dorsally, consisting of cephalosome, 4-segmented metasome, and 3-segmented genitoabdomen. Body length 1.69 mm; maximum width 350 μm across fourth pedigerous somite; maximum dorsoventral depth 380 μm at fourth pedigerous somite. Cepha- losome narrower than metasome, defined from metasome by indistinct articulation. Metasome gradually broadening posteriorly; somites defined from one another by constrictions. Genitoabdomen ( Fig. 92B, C ) as long as wide (215×220 μm), tapering, consisting of genital and 2 abdominal somites. Genital somite bearing transverse stripe dorsally; genital apertures positioned dorsolaterally. Second abdominal somite distinctly narrower than first. Left and right caudal rami completely fused with each other ( Fig. 92D ), each bearing 1 conical spine on distal margin and 1 seta on lateral margin.

Rostrum absent. Antennule ( Fig. 92E ) longer than wide, distinctly 2-segmented, armed with 1 seta distally on proximal segment, and cluster of about 12 setae around apex of segment; all setae short and bluntly tipped. Antenna ( Fig. 92G ) 2-segmented; proximal segment swollen, unarmed; distal segment about 1.5 times longer than wide, armed with 4 spines, proximal spine minute and simple, 3 distal spines larger and bifurcate.

Labrum ( Fig. 92G ) simple, unornamented with sclerotized posterior margin. Mandible ( Fig. 92G ) as weak lobe positioned lateral to labrum, each tipped with 1 small, nipple-shaped element. Maxillule and maxilla absent. Maxilliped ( Fig. 92H ) small, stout, 4-segmented; proximal 3 segments unarmed, each wider than long; terminal segment bearing unequally bifurcate claw.

Legs 1-4 each consisting of protopod and exopod; endopod not discernible. Exopods with short inner margin and much longer outer margin, armed only with spines (lacking seta). Two terminal spines on each exopod fused at base (arising from common base). Leg 1 ( Fig. 92I ) exopod armed with 5 spines and ornamented with many spinules on anterior surface. Legs 2 ( Fig. 92J ), 3 and 4 shaped and ornamented as leg 1, but armed with 4 spines (with 2 terminal spines fused at base).

Leg 5 ( Fig. 92C ) as short, blunt posterolateral tubercle on compound last metasomite bearing 1 or 2 small setae. Leg 6 ( Fig. 92K ) represented by 1 small spine and 1 spiniform process; 4 dentiform elements on surface adjacent to leg 6.

Male. Unknown.

Remarks. While describing eaplçstçma junctum Ooishi, 2009 as an associate of budẚstçma sp. in Madagascar, Ooishi (2009b) mentioned that this copepod was the only species of eaplçstçma to have medially fused caudal rami. eaplçstçma manadçense sp. nov. is the second species characterised by the possession of medially fused caudal rami and is, therefore, compared in detail with e. junctum. The new species differs from e. junctum as follows: (1) the fused caudal rami are clearly articulated from the anal somite (cf. indistinctly articulated in e. junctum); (2) the caudal rami are armed with 1 spine and 1 seta (cf. armed only with 1 spine in e. junctum); (3) the first segment of the antennule is not expanded (cf. markedly expanded in e. junctum); (4) the two terminal spines on the exopods of legs 1-4 are fused at base (cf. these spines separate from each other in e. junctum); and (5) and the mandible is tipped with a rudimentary setal element (cf. tipped with 2 setae in e. junctum).

Figures

FIG. 92. eaplçstçma manadçense sp. nov., female. A, habitus, right; B, distal part of body, right; C, distal part of body, dorsal; D, anal somite, dorsal; E, antennule; F, antenna; G, labrum and mandibles; H, maxilliped; I, leg 1; J, leg 2; K, genital aperture. Scale bars: A, 0.2 mm; B, C, 0.1 mm; D-K, 0.02 mm.