Scalopidia spinosipes, 1858

Ng, Peter K. L. & Castro, Peter, 2013, On the genus Scalopidia Stimpson, 1858 (Crustacea: Brachyura: Goneplacoidea: Scalopidiidae), with the description of one new genus and three new species, Zootaxa 3731 (1) : -

Scalopidia spinosipes, 1858

( Figs. 1 , 2 A–D, 3, 5A, 6A, 7A–D, 8A, B, 9A, B, 10A, B, 11A, B, 12A–D, 14A)

Scalopidia spinosipes Stimpson 1858: 95 .—Rathbun 1910: 344, pl. 2 fig. 2.—Tesch 1918: 224, pl. 14 fig. 3.—964: 235, fig. 14; 1968: 92.—Evans 1967: 407.—Fang 1991: 352.—Huang 1994: 592.—Ng et al. 2001: 74, pl. 7f. —Ng et al. 2008: 85.— Ya ng et al. 2008: 771.—Guinot et al. 2013: 118, 294 (part).

Hypophthalmus leucochirus Richters , in Lenz & Richters, 1881: 429, pls. 1–10.

Scalopidia leucochirus .—Serène 1964: 235.

Scalopidia leuchochirus [sic].—Serène 1968: 92.—Ng et al. 2008: 85.

Material examined. Hong Kong: lectotype male (here designated) (9.3× 12.1 mm), paralectotype female (13.3× 17.7 mm) (Stimpson Collection, NHM 61.44).— 1 male (14.8× 19.2 mm) (ZRC 2006.0073), among shellfish, Tai Po Wet market, Hong Kong, coll. P.K.L. Ng, 2006. Singapore: 1 male (ZRC 1989.3671), off Bedok, in mud, dredge, coll. P.K.L. Ng, 27 October 1982.— 1 male (12.2× 16.7 mm) (ZRC 2000.1604), Southern Islands, dredge, coll. D. Lane, 1992.— 1 female (ZRC 2000.1455), off Tanah Merah Jetty, 26 m, 118’13.8” N 10359 ’46.9”E, coll. L.W. Loh et al., 29 August 1997. Indonesia: 1 male (16.1× 11.8 mm) (ZRC 1969.10.13.2), coll. RV Djalanidhi, R. Serène, 6 October 1967. South China Sea: 1 male (ZRC 1985.1627), near Horsburgh Lighthouse, South China Sea, coll. H. Huat, June 1983.— 6 males (largest 14.8× 20.4 mm), 11 females (largest 14.2× 19.2 mm), 1 juvenile (ZRC 2000.1343), about 30 miles from Horsburgh Lighthouse, South China Sea, coll. H. Huat, 10 September 1983. Gulf of Thailand: 3 males, 1 female (ZRC 2013.1414), Sri Racha Fish Port, 20 m, near Chonburi, Thailand, coll. trawlers, J. Lai & N.K. Ng, 17 March 2005.— 1 female (ZRC 2008. 0190), Sri Racha Fish Port, 20 m, near Chonburi, Thailand, coll. trawlers, N.K. Ng et al., 18 March 2005.— 2 males (larger 19.1× 26.3 mm) (ZRC 2013.1413), Sri Racha Fish Port, 20 m, near Chonburi, Thailand, coll. trawlers, J. Lai & N.K. Ng, 19 March 2005.— 4 males, 1 female (ZRC 1997.672), Chonburi Port, 20 m, Thailand, coll. trawlers, P. Naiyanetr, 1996. — 1 male (ZRC 2000.23), Angsila Port, near Chonburi, 20 m, Thailand, coll. trawlers, P.K.L. Ng, November 1999.— 1 male (ZRC 2013.1410), Angsila Port, near Chonburi, 20 m, Thailand, coll. trawlers, P.K.L. Ng, 20 February 2000.— 4 males, 2 ovigerous females, 3 females (ZRC 2000.0886), Angsila Port, near Chonburi, 20 m, Thailand, coll. trawlers, P.K.L. Ng, 20 February 2000. Vietnam: 1 male (17.8×13.0 mm) (ZRC 1969.11.25.1), coll. Fisheries UNDP Vietnam, R. Serène, 25 November 1969. Philippines: 1 juvenile male (ZRC 2013.1423), station D10, Bohol Sea, coll. PANGLAO 2004 Expedition, 20 June 2004.— 1 juvenile female (ZRC 2013.1424), station S25, Bohol Sea, coll. PANGLAO 2004 Expedition, 23 June 2004.— 1 female (12.5× 9.2 mm) (ZRC 2013.1425), station T23, Bohol Sea, coll. PANGLAO 2004 Expedition, 21 June 2004.

Diagnosis. Carapace subovate, lateral margins convex ( Fig. 2 A–D); dorsal carapace surface uneven with regions of different convexities ( Figs. 2 A–D, 5A); cornea with pigmentation in centre ( Figs. 3 B, 5A); cheliped carpus with long sharp tooth on inner dorsal angle, distal margin very finely granular or almost smooth; P2 merus dorsal margin with sharp granules and/or short spines, ventral margin with row of sharp spines ( Figs. 2 C, D, 3A); P2 carpus unarmed ( Figs. 2 C, D, 3A); P2 propodus with row of spines on dorsal margin ( Figs. 2 C, D, 3A); P3, P4 merus dorsal margins with strong spines, ventral margin with 2 rows of sharp spines ( Figs. 2 C, D, 3A); P3, P4 carpus each with rows of strong spines on dorsal margin, with low subdorsal ridge; P3, P4 propodus each with strong spines on dorsal, ventral margins ( Figs. 2 C, D, 3A); P5 merus with strong spines on dorsal margin, ventral margin with numerous strong spines on proximal half ( Figs. 2 B–D, D, 3A, 8A, B); surface of thoracic sternum mostly smooth or pitted, surface near sterno-abdominal cavity with low, flattened granules ( Fig. 9 A, B); episternite 7 as tranversely elongated subrectangular plate ( Fig. 9 B); male abdominal somite 6 as wide as long ( Figs. 9 A, 10A, B); G1 distal part elongated, tip prominently open distally, slightly flared ( Fig. 12 A-C).

Variation. Females are similar to males in non-sexual characters. Their chelipeds are almost equal but the two chelae do not differ substantially in structure except the difference in size. The same is true for young male specimens. Large male specimens, however, have very unequal and heteromorphic chelipeds; with the pollex prominently curved, as well as very different palm and finger structures and dentition ( Fig. 7 C, D). Small males ( Fig. 7 A) and females have the outer surface of the chela pitted, setose to different degrees, the fingers relatively shorter, and less curved with the teeth well developed ( Fig. 7 A). As males become larger, the pollex curves more substantially ( Figs. 3 D, 7B).

Remarks. Evans (1967: 407) listed two dried syntype specimens of Scalopidia spinosipes as NHM 61.44. Both specimens were examined ( Fig. 2 A, B), and although in poor condition, they are easily identifiable with Stimpson’s species. The male is here designated as the lectotype. They agree very well with a fresh male specimen from Hong Kong (ZRC 2006.0073).

We disagree with Serène (1964, 1968) in treating S. leucochirus as a distinct species. Scalopidia leucochirus was described on the basis of one male measuring 19 × 14 mm from Hong Kong infected with the rhizocephalan Sacculina . The figures of the species by Richters (in Lenz & Richters 1881: pls. 1–10) ( Fig. 3 ) show no major differences with the large series of specimens of S. spinosipes we have from East and Southeast Asia, particularly in the armature of ambulatory legs. There is one discrepancy. The figure of the male abdomen of Hypophthalmus leucochirus by Richters (in Lenz & Richters 1881: pl. 10) ( Fig. 3 F) is unusual because somite 6 is depicted as being much longer than wide. It is quite unlike any seen in any Scalopidia species and is almost certainly incorrectly drawn.

Figures

FIGURE 1. Posterior thoracic sternum and male abdomen of Scalopidia spinosipes, male (12.2 × 16.7 mm) (ZRC 2000.1604), Singapore. Symbols: a 3 = abdominal somite 3; cx 3 – 5 = coxae 3 – 5, respectively; G 1 — male first gonopod; p = penis; s 5 – 8 = thoracic sternites 5 – 8, respectively.

FIGURE 2. Overall views. Scalopidia spinosipes: A, lectotype male (9.3 × 12.1 mm) (NHM 61.44), Hong Kong; B, paralectotype female (13.3 × 17.7 mm) (NHM 61.44), Hong Kong; C, male (14.8 × 19.2 mm) (ZRC 2006.0073), Hong Kong; D, male (12.2 × 16.7 mm) (ZRC 2000.1604), Singapore; E, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; F, female (14.2 × 19.2 mm) (ZRC 2000.1343), South China Sea. Scalopidia indica n. sp.: G, holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea; H, paratype female (10.0 × 13.1 mm) (ZRC 1992.10459 - 10461), Penang. Scalopidia spectabilis n. sp.: I, holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea.

FIGURE 3. Hypophthalmus leucochirus Richters, in Lenz & Richters, 1881 (after Lenz & Richters 1881: pls. 1, 7 – 10).

FIGURE 7. Outer views of chelae. Scalopidia spinosipes: A, lectotype male (9.3 × 12.1 mm) (NHM 61.44), Hong Kong; B, male (14.8 × 19.2 mm) (ZRC 2006.0073), Hong Kong; C, D, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; E, F, Scalopidia indica n. sp.: G, holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea; G, H, Scalopidia spectabilis n. sp., holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea.

FIGURE 9. Male thoracic sternum and abdomen. A, B, Scalopidia spinosipes, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; C, D, Scalopidia indica n. sp., holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea; E, F, Scalopidia spectabilis n. sp., holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea; G, H, Caenopedia ocularia n. sp.: holotype male (11.2 × 15.0 mm) (MNHN-IU- 2010 - 1573), Madagascar.

FIGURE 12. Gonopods. A – D, Scalopidia spinosipes, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; E – H, Scalopidia indica n. sp., holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea. A – C, E – G, left G 1 s; D, H, left G 2 s. Scales: A, D, E, H, 1.0 mm; B, C, F, G = 0.5 mm.