Luidia quinaria

Liu, Wei, Liao, Yulin & Li, Xinzheng, 2006, Luidia changi, a new sea star species (Echinodermata: Asteroidea: Luidiidae) from the Yellow Sea, with a review of two related species, Zootaxa 1315, pp. 57-68 : 58-60

Luidia quinaria von Martens, 1865

( Figs. 1 , 2 , 5 A, B, 6A, D)

Luidia maculata var. quinaria von Martens, 1865: 352.

Luidia limbata Sladen, 1889: 252 , Pl. 44 figs. 3–4, Pl. 45 figs. 7–8.

Luidia singapurensis (Grube MS.) Sladen, 1889: 253.

Luidia quinaria – Ives, 1891: 211, Pl. 9 figs. 5–9; Fisher, 1911: 247; Goto, 1914: 293, Pl. 7 figs. 104–112; Dderlein, 1920: 275, Pl. 20 fig. 26; Uchida, 1928: 788; Chang, 1948: 35, Pl. 1 figs. 1–2, Pl. 2 figs. 1–2; Clark, 1953: 392, Fig. 9; Chang et al.,1964: 55; Hayashi, 1973: 41, Pl. 7 fig.1; Blake, 1973: 38; Imaoka et al., 1990: 39; Liao & Clark, 1995: 72, Fig. 38; Chao, 2000: 279, Fig. 5 .

Material examined: 5 ex., CN 54­09, [23.44°N, 117.03°E], coll. Wu, 10 Mar.1954; 2 ex., CN 54­34, [23.27°N, 116.61°E], coll. Wu, 17 Mar.1954; 1 ex., CN 18­37, [35.06°N, 120.5°E], 36m, 20 Oct.1958; 1 ex., CN 21­18, [35.48°N, 119.85°E], 20m, 21 Nov.1958; 7 ex., CN V236B­44, [29.1°N, 124.02°E], muddy sand, 82m, coll. Lin, 3 Apr.1959; 7 ex., CN V248B­11, [28.05°N, 122.02°E], soft mud, 52m, BT, 7 Apr.1959; 1 ex., CN D40B­29, [28.01°N, 123.09°E], muddy sand, 84m, coll. Cheng, 1 Jul.1959; 1 ex., CN D58B­20, [29.01°N, 122.22°E], soft mud, 28m, BT, coll. Cheng, 8 Jul.1959; 2 ex., CN D59B­24, [29°N, 122.53°E], soft mud, 53m, BT, coll. Cheng, 9 Jul.1959; 7 ex., CN D76B­31, [29.23°N, 122.46°E], soft mud, 46m, BT, coll. Cheng, 12 Jul.1959; 2 ex., CN D72B­26, [30.03°N, 122.73°E], soft mud, 40m, BT, coll. Cheng, 12 Jul.1959; 11 ex., CN y306B­8, [35.03°N, 119.58°E], muddy sand, 18m, coll. Huang, 19 Jul.1959; 1 ex. CN D79B­34, [30.5°N, 123.58°E], muddy sand, 63m, 10 Aug.1959; 8 ex., CN D82B­19, [31°N, 123.5°E], sandy mud, 55m, 11 Aug.1959; 14 ex., CN 001­23, [35.96°N, 120.58°E], 8 Sep.1958; 3 ex., [27.5°N, 121.13°E], CN 79­03, Oct.1979; 12 ex., CN V319B­35, [31.02°N, 123°E], muddy sand, 51.6m, coll. Cheng, 25 Oct.1959; 11 ex., CN V52 B­24, [26.5°N, 122.02°E], fine sand, 104m, 29 Oct.1976; 2 ex., CN D51B­24, [28.54°N, 122.07°E], soft mud, 20m, BT, coll. Cheng, 5 Dec.1959; 5 ex., CN F40B­9, [30.46°N, 123.01°E], sandy mud, 57m, AT, 6 Dec.1959; 1 ex., CN F42B­14, [30.5°N, 124.18°E], muddy sand, 56m, AT, coll. Zhang, 7 Dec.1959; 1 ex., CN F43B­54, [30°N, 124.03°E], sand, 57m, AT, coll. Liang, 7 Dec.1959; 1 ex., CN F47­26, [30.01°N, 123.04°E], muddy sand, 54m, AT, coll. Liang, 8 Dec.1959.

Diagnosis: 5 rays, R:r =4.79–8.66. Arms with a distinct dark area in disk center and along midradial line. Large abactinal paxillae, about 280 m high and the top 220 m wide, usually with 10–20 central granules and 20–30 peripheral granular spinelets. Paxillae in disc center and along midradial line smaller, with fewer central granules and peripheral spinelets, and with a tendency to become irregular in form. Commonly superomarginal plates with 1–2 bivalvate pedicellariae arranged in a longitudinal series along side of rays. Mouth plates with 1 or 2 pairs of slender two­jawed pedicellariae, about 1.3–1.5 mm long.

Inferomarginal plates, large, with a large flat spine at abactinal corner, about 1.6–2.5 mm long, mostly with one large bicuspid pedicellaria near base of this spine. Each adambulacral plate with 3 flat spines aligned perpendicular to furrow, innermost and 2nd slightly curved, outermost spine straight, mostly with large slender bicuspid pedicellaria at base.

Distribution: Common, from the Yellow Sea to western Guangdong in the South China Sea ( Fig. 1 ), also from Hokkaido to Kyushu in Japan. Depth 17– 84 m.

Remarks: The material is consistent with the original description of the type specimens. Adults can be easily recognized, with their broad arms with conspicuous dark midline, distinctly granuliform spinelets of paxillae and very slender pedicellariae on the actinal surface. Young specimens are somewhat difficult to distinguish from L. yesoensis since they have shorter arms and the dark radial midline is less distinct. Removal of soft tissue with sodium hypochlorite to check the abactinal plates ( Fig. 5 A–B), revealed that the quadrangular paxillae are thick, with slightly convex top; between imbricating quadrangular paxillar plates very small ossicles can be seen in actinal view. After examination of abactinal spinelets ( Fig. 6 A, D), we find that the rather squat central spinelets of paxillae consistently have many subequal transparent spinules.

Figures

FIGURE 1. Collection localities of the three species, Luidia changi sp. nov., L. quinaria von Martens, 1865 and L. yesoensis Goto, 1914.

FIGURE 2. Luidia quinaria von Martens, 1865 (CN 21 – 18, R = 72 mm). A, abactinal view; B, actinal view; C, arm, dorsal view; D, arm, ventral view. Scale = 5 mm.

FIGURE 5. Denuded abactinal plates, proximal base of ray. A – B, Luidia quinaria von Martens, 1865; C – D, Luidia yesoensis Goto, 1914; E – F, Luidia changi sp. nov. A, C, aboral view, paxillae with raised top (arrow); B, oral view, thick, with very small plates (arrow); D, oral view, thick, paxillae along the median radial line distinctly smaller (arrow); E, aboral view, paxillae with flat top, with very small lateral paxillae (arrow); F, oral view, thin, with very small plates (arrow). Scale = 2 mm.

FIGURE 6. Abactinal spinelets. A, D, Luidia quinaria von Martens, 1865; B, E, Luidia yesoensis Goto, 1914; C, F, Luidia changi sp. nov. A – C, central granules (arrow); D – F, peripheral spinelets (arrow). Scale = 100 m.