Parapolycope setouchiensis, Tanaka & Tsukagoshi & Karanovic, 2014

Tanaka, Hayato, Tsukagoshi, Akira & Karanovic, Ivana, 2014, Molecular phylogeny of interstitial Polycopidae ostracods (Crustacea) and descriptions of a new genus and four new species, Zoological Journal of the Linnean Society 172 (2), pp. 282-317 : 293-300

publication ID	https://doi.org/ 10.1111/zoj.12176
DOI	https://doi.org/10.5281/zenodo.10542092
persistent identifier	https://treatment.plazi.org/id/03AEFF7E-FFFB-FFB4-FCA1-F526FC1396A8
treatment provided by	Marcus
scientific name	Parapolycope setouchiensis
status	sp. nov.

Treatment

PARAPOLYCOPE SETOUCHIENSIS View in CoL SP. NOV.

( FIGS 10–16 View Figure 10 View Figure 11 View Figure 12 View Figure 13 View Figure 14 View Figure 15 View Figure 16 )

Type series

Holotype: adult male (SUM-CO-2201), right valve length 294 μm and height 220 μm, left valve length 288 μm and height 217 μm, soft parts mounted on slide and valves preserved in a cardboard cell slide, Paratypes: eight adult males (SUM-CO-2202–2209) and nine adult females (SUM-CO-2210–2218).

Type locality

The holotype specimen was collected from Kitagi island Beach , Kasaoka City, Okayama Prefecture, the Seto inland sea of Japan, 34°22′29′′N, 133°31′54′′E ( Fig. 1C View Figure 1 ), on 11 October 2009; interstitial environment at 20 cm below the sand surface at 5 m inland from the low tide shoreline. The substrate consisted mainly of very coarse, decomposed granite sand GoogleMaps .

Diagnosis

Carapace oval in lateral view. Carapace surface covered with a number of shallow pits. Serration along anterior margin with 24 and 22 sharp processes on right valve and left valve, respectively, a dorsal-most process of right valve prominently large. Uropodal projection of male long, with numerous prominent spines or barbs. Three claws on each uropodal lamella in female. Male copulatory organ consisting of extending helical tube.

Description of adult male

Carapace ( Figs 10 View Figure 10 , 11A–E View Figure 11 , 12 View Figure 12 ). Right valve length 285– 297 μm and height 208–220 μm, left valve length 280– 292 μm and height 211–218 μm ( Table 3). Carapace oval in lateral view. Carapace surface covered with a number of shallow pits ( Fig. 11A, B View Figure 11 ). Serration along anterior margin with 24 and 22 sharp processes on right valve and left valve, respectively ( Fig. 10 View Figure 10 ), a dorsal-most process of right valve prominently large. Adductor muscle scars oval and consisting of three closely spaced scars ( Fig. 10 View Figure 10 ). Marginal infold of each valve developed along anterior to posteroventral margins ( Figs 11C, D View Figure 11 , 12B, F, G, L View Figure 12 ). Along inner margin of right valve, bar and groove on anterodorsal to dorsal end ( Fig. 12A View Figure 12 ), one socket (part of hinge structure) developed at dorsal end ( Fig. 12C View Figure 12 ), posterior bar on mid-dorsal to posteri- or end ( Fig. 12D View Figure 12 ), bar and groove on posterior to midposteroventral end ( Fig. 12E View Figure 12 ). Along inner margin of left valve, bar and groove on anterodorsal to dorsal end ( Fig. 12H View Figure 12 ), one knob (part of hinge structure) developed at dorsal end ( Fig. 12I View Figure 12 ), bar on mid-dorsal to posterior end ( Fig. 12J View Figure 12 ), and bar along posteroventral margin ( Fig. 12K View Figure 12 ).

Bellonci organ. Absent.

Upper lip ( Figs 13A View Figure 13 , 14A, B View Figure 14 ). Broad chitinous hook and a chain of cone-shaped setae on right lateral side. Distal part with anteroventral protrusion, tapering to wrinkled, and papilla-shaped termination in lateral view.

Antennula ( Fig. 13B, B′ View Figure 13 ). Uniramous, four articulated podomeres. First podomere quadrate, with setulae on dorsal margin, lateral surface and ventrodistal end. Second podomere about 1.5 times as long as first podomere, proximal half of dorsal cuticle thick and with an inward bulge, with one annulated setulous seta at dorsoproximal end, one cluster of setae on middle of dorsal margin, and three tufts of setulae on lateral surface. Third podomere about two-thirds as long as first podomere, with one short, simple seta at dorsodistal end and five ventrodistal setae consisting of one seta with large disc-shaped sucker, one seta curving at tip armed with five falciform spines and minute setulae, one seta with comb-like setulae, and two simple setae. Fourth podomere small, with five long annulated setae.

Antenna ( Fig. 13C, C′ View Figure 13 ). Typically biramous, with exopodite and endopodite consisting of nine and three podomeres, respectively. Basis triangular tapered distally. Exopodite: first podomere half as long as basis. Podomere length decreasing in size from second to eighth, each podomere with one long annulated seta; ninth (distal-most) podomere very small, with one long annulated seta at proximal, one medium annulated seta with short process and one short seta at distal end. Endopodite: first podomere half as long as basis. Second podomere two-thirds as long as first podomere, with three setae along dorsal margin consisting of one medium annulated and two short, and six annulated setae at distal consisting of three long, one long with some filaments, one medium, one short. Third podomere one-quarter as long as first podomere, with one stout, hook-shaped claw extending backward, one long annulated seta at ventral margin, and one long and one medium annulated seta at distal end.

Mandibula ( Fig. 13D View Figure 13 ). Coxal endite with four sharp teeth. Basis with three plumose setae on ventral margin and one annulated setulous seta on dorsal margin. Endopodite consisting of two podomeres. First podomere with two annulated plumose setae on ventral margin near proximal end and two annulated plumose long setae at dorsodistal end. Second podomere very small with setulae on dorsal margin, bearing one medially plumose and one claw-like, setulous annulated seta.

Maxillula ( Fig. 13E, E′ View Figure 13 , E″). Precoxa ( Fig. 13E′ View Figure 13 ) with ten annulated plumose setae of different lengths. Coxa ( Fig. 13E View Figure 13 ″) with one short and one medium plumose setae on lateral surface near ventroproximal margin, one short plumose setae on lateral surface near ventral middle margin, three medium plumose setae on ventral margin, and two tufts of setulae on dorsal margin. Basis with one short, one medium annulated, and two long plumose setae on ventral margin, and setulae along ventral and dorsal margins. First podomere of endopodite with one annulated setulous seta dorsodistally, and one long annulated and one long plumose seta at ventroproximal margin. Second podomere with two long, annulated setulous setae and two long, stout setulous setae with few bilateral spines. Exopodite consisting of two podomeres. First podomere with setulae along dorsal margin. Second podomere with

LV, left valve; RV, right valve.

one very long, stout setulous seta, four long and three medium annulated setae on ventral margin, and one tuft of setulae on dorsal margin.

Fifth limb ( Fig. 13F, F′ View Figure 13 ). Coxa bearing epipodite with 12 long plumose setae and two short setulous setae on dorsodistal margin. Basis with three plumose setae along dorsal margin and one slender, annulated setulous seta on ventral margin. Endopodite with one short, plumose annulated, one medium annulated, and two long plumose setae. Exopodite with one stout setulous seta.

Uropod ( Figs 14B, C View Figure 14 , 15A View Figure 15 ). Left lamella with three stout claws and three rows of setae on anteroventral surface. Right lamella with four stout claws and ventrodistally situated uropodal projection, which is long, flexible, and covered with numerous prominent spines.

Male copulatory organ ( Fig. 15A View Figure 15 ). Arising from outer surface of body on left side of terminal trunk segment as a long stretched helically tube.

Description of adult female

Mandibula, maxillula, and fifth limb similar to those of adult male.

Carapace ( Fig. 11F–J View Figure 11 ). Right valve length 301– 319 μm and height 218–234 μm, left valve length 294– 321 μm and height 219–234 μm ( Table 3).

Upper lip ( Fig. 16A View Figure 16 ). Semicircular in lateral view. A number of setae on lateral surface.

Antennula ( Fig. 16B View Figure 16 ). Uniramous, four articulated podomeres. First podomere quadrate, with two tufts of setulae on dorsal margin. Second podomere about 1.5 times as long as first podomere, proximal half of dorsal cuticle robust and with inward bulge, with one annulated setulous seta at dorsoproximal end, one cluster of setae on middle of dorsal margin, and two tufts setulae on lateral surface. Third podomere about two-thirds as long as first podomere, with one short simple seta at dorsodistal end, two short simple setae on ventrodistal end, and setulae along dorsal margin. Fourth podomere small, with five long annulated setae.

Antenna ( Fig. 16C View Figure 16 ). Only second and third podomeres of endopodite differing from those of adult male. Second podomere, with one annulated setulous seta on dorsodistal end and six annulated setae at distal consisting of three long, one long with some filaments, one medium, one short. Third podomere one-quarter as long as first podomere, with one long annulated seta at ventral margin, and one long and one medium annulated seta at distal end.

Uropod ( Fig. 15B View Figure 15 ). Each lamella with three claws. Right lamella with three rows of setae on anteroventral surface.

Female copulatory organ ( Fig. 15B View Figure 15 ). Female spermatheca double twisted tube in lateral view.

Dimensions

See Table 3.

Distribution

Tai Beach (Kyoto Pref. 35°34′53′′N, 135°14′09′′E), Komatsubara (Kagawa Pref. 34°15′10′′N, 134°22′33′′E), Aji (Kagawa Pref. 34°23′48′′N, 134°07′44′′E), Kitagi island Beach (Okayama Pref. type locality, 34°22′29′′N, 133°31′54′′E), Meotoura (Miyazaki Pref. 31°29′36′′N, 131°23′04′′E), Injo Beach (Kagoshima Pref. 30°33′27′′N, 131°01′32′′E). All specimens were collected by Hayato Tanaka from interstitial pore water in Japan GoogleMaps .

Etymology

This species is named after the type locality, the Seto inland sea of Japan .

Remarks

Appendage morphology of Pa. setouchiensis sp. nov. is similar to that of Parapolycope spiralis Tanaka & Tsukagoshi, 2010 . However, the new species can be easily distinguished from Pa. spiralis by the characteristics of the male uropodal projection. Namely, males of the new species bear a number of prominent spines on the uropodal projection, whereas they are absent in Pa. spiralis .