Neanthes kinmenensis, Hsueh, 2019

Hsueh, Pan-Wen, 2019, Neanthes (Annelida: Nereididae) from Taiwanese waters, with description of seven new species and one new species record, Zootaxa 4554 (1), pp. 173-198 : 183-185

Neanthes kinmenensis n. sp.

Figs 9A – G , 10A – E , Table 2

Material examined. Holotype ( NMNS 7946-027 ), Yangshan (24°27.43´N 118°18.12´E), Kinmen County, Fujian, intertidal soft bottom, 21 February 2001 . Paratype: 1 specimen ( NMNS 7946-028 ), collection location, habitat and date information same as holotype .

Description. Holotype, incomplete, posterior end missing, remaining body length 58 mm (72.0) with 83 (110) chaetigers, maximum width 3.0 mm at chaetiger 3 (4), excluding parapodia; beige in alcohol ( Fig. 9A ). Prostomium wider than long, one pair antennae arise antero-laterally; palpophores spherical and biarticulate with sub-conical palpostyles, four pairs of tentacular cirri, longest posterior tentacular cirri reaching chaetiger 2 ( Fig. 9B ). Two pairs of black eyes, in trapezoidal arrangement, anterior pair larger than posterior pair. One apodous anterior segment present, about 1.4 times as long as chaetiger 1. Pharynx with dark brown jaws, each with 5–6 lateral teeth; brown to dark conical paragnaths as: I=3 (4), in a triangle (in a diamond-shaped arrangement with 4); II=10 (13) (left), 11 (15) (right), in 2–3 oblique rows; III=28 (31), in 3–4 transverse rows; IV=22 (24) (left), 23 (20) (right), in 3–4 transverse rows; V=3, in a triangle; VI=2 (left), 2 (3) (right), in a transverse row; VII/VIII=46, in 2– 3 rows ( Fig. 9C ).

Notopodial dorsal ligule narrowed triangular with a pointed tip throughout ( Fig. 9 D–G). Dorsal cirri attached basally to dorsal ligule throughout, shorter than dorsal ligules ( Fig. 9 D–G). Notopodial ventral ligule narrowed triangular with a pointed tip on anterior chaetigers, less developed in posterior chaetigers. Neuropodium with prominent inferior and superior lobes, both lobes elongate projecting beyond neuropodial postchaetal lobe on anterior chaetigers, both lobes less developed on posterior chaetigers. Neuropodial postchaetal lobe present, triangular with a blunt tip throughout. Ventral notopodial ligule digitiform throughout; ventral cirri mid-ventrally attached to ventral edge of parapodia, shorter than ventral ligule ( Fig. 9 D–G).

Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers ( Fig. 10A ). Neurochaetae dorsal fascicle: homogomph spinigers ( Fig. 10B ), and heterogomph falcigers with long, serrated terminal blade ( Fig. 10C ); Neurochaetae ventral fascicle: heterogomph spinigers ( Fig. 10D ), and heterogomph falcigers with long, serrated terminal blade ( Fig. 10E ). Pygidium not observed.

Etymology. The name is derived from the name of the island, Kinmen, where the worm was collected.

Type locality. Yangshan, Kinmen County, Fujian .

Distribution. Only known from the type locality.

Remarks. Neanthes kinmenensis n. sp. is similar to N. donghaiensis from China and N. vitabunda from Philippines, which have 3 conical paragnaths on Area V of the pharynx ( Pflugfelder 1933: 72, fig. 12b; Wu et al. 1981: 132; Table 2). Neanthes kinmenensis n. sp., however, can be distinguished from N. donghaiensis by having greater numbers of conical paragnaths on Areas I, IV & VII/VIII of the pharynx (3–4, 20–28 & 46 versus 1–2, 7–9 & 20–23, respectively) ( Wu et al. 1981: 132; Table 2). Neanthes kinmenensis n. sp. differs from N. vitabunda by having homogomph spinigers, heterogomph spinigers and heterogomph falcigers in neuropodia ( Table 2). The latter species has only homogomph spinigers and heterogomph falcigers in neuropodia ( Pflugfelder 1933: 72, fig. 12d). Of the three species described with 3 conical paragnaths on Area V of the pharynx in the present study, N. kinmenensis n. sp. is somewhat similar to N. babuzai n. sp. in terms of conical paragnath counts on Areas I, II, IV, VI & VII/VIII of the pharynx and the presence of long neuropodial heterogomph falcigers ( Figs 2C, E , 10C, E ; Table 2). However, N. kinmenensis n. sp. has fewer conical paragnaths on Area III of the pharynx than that of N. babuzai n. sp. (28–31 versus 49–63) ( Table 2). Moreover, the longest posterior tentacular cirri of N. kinmenensis n. sp. reach only to chaetiger 2, whereas that of N. babuzai n. sp. reaches to 4–9 chaetigers ( Table 2). Neanthes kinmenensis n. sp. differs from N. jihueiensis n. sp. by having long neuropodial heterogomph falcigers, comparing to medium-length heterogomph falcigers in the latter species ( Fig. 10C, E ; Table 2).

Figures

FIGURE 2. Neanthes babuzai n. sp.; holotype (NMNS 7946-001): A, notochaeta, homogomph spiniger, chaetiger 142; B, neurochaeta of dorsal fascicle, homogomph spiniger, chaetiger 129; C, neurochaeta of dorsal fascicle, long heterogomph falciger, chaetiger 129; D, neurochaeta of ventral fascicle, heterogomph spiniger, chaetiger 129; E, neurochaeta of ventral fascicle, long heterogomph falciger, chaetiger 129. Scale: A–E, 0.05 mm.

FIGURE 9. Neanthes kinmenensis n. sp.; holotype (NMNS 7946-027): A, whole animal; B, anterior body; C, paragnaths of the pharynx; D, right parapodium, anterior view, chaetiger 11; E, right parapodium, posterior view, chaetiger 11; F, right parapodium, anterior view, chaetiger 73; G, right parapodium, posterior view, chaetiger 73. Abbreviations: DC, dorsal cirrus; IL, inferior lobe; NePL, neuropodial postchaetal lobe; NeVL, neuropodial ventral ligule; NoDL, notopodial dorsal ligule; NoVL, notopodial ventral ligule; SL, superior lobe; VC, ventral cirrus. Scale: A, 5.0 mm; B–C, 1.0 mm; D–G, 0.1 mm.

FIGURE 10. Neanthes kinmenensis n. sp.; holotype (NMNS 7946-027): A, notochaeta, homogomph spiniger, chaetiger 82; I, neurochaeta of dorsal fascicle, homogomph spiniger, chaetiger 82; J, neurochaeta of dorsal fascicle, heterogomph falciger, chaetiger 82; K, neurochaeta of ventral fascicle, heterogomph spiniger, chaetiger 82; L, neurochaeta of ventral fascicle, heterogomph falciger, chaetiger 82. Scale: A–E, 0.05 mm.