Oxypleurodon stimpsoni Miers, 1885

Lee, Bee Yan, Forges, Bertrand Richer De & Ng, Peter K. L., 2017, Deep-sea spider crabs of the families Epialtidae MacLeay, 1838 and Inachidae MacLeay, 1838, from the South China Sea, with descriptions of two new species (Decapoda, Brachyura, Majoidea), European Journal of Taxonomy 358, pp. 1-37 : 5-8

Oxypleurodon stimpsoni Miers, 1885

Figs 2 A–C, 3A–C, 13B

Oxypleurodon stimpsoni Miers, 1885: 588 (type locality: Ki Islands, Banda Sea, Indonesia).

Oxypleurodon stimpsoni – Miers 1886: 26 (list), 29 (list), 38–39, pl. 6 fig. 1a–b. — Ho et al. 2004: 648, fig. 3E. — Ng et al. 2008: 105 (list). — Richer de Forges & Ng 2009b: 248 (table), 251, 253, fig. 7A. — Froglia & Clark 2011: 51 . — Lee et al. 2015: 1257, fig. 1A.

Sphenocarcinus stimpsoni – Takeda 1982: 121, un-numbered text-fig. — Guinot & Richer de Forges 1986: 135 (key), 136, figs 19C–D, 21A–B, pl. 8 figs G–I.

(For complete synonymy, see Richer de Forges & Ng 2009b: 251.)

Material examined

SOUTH CHINA SEA: 1 ♂ (14.0 × 9.0 mm) [photographed] ( ZRC 2016.0072), 1 ♂ (10.5 × 7.1 mm), 1 ♀ (13.3 × 9.3 mm), 1 ovigerous ♀ (14.2 × 9.5 mm) ( ZRC 2016.0071), 1 ♀ (9.0 × 5.5 mm), 1 ovigerous ♀ ( NTOU), 1 ♀ (11.8 × 7.7 mm), 1 ovigerous ♀ (11. 8 × 7.6 mm) (MNHN-IU-2016-175), continental slope, Dongsha, stn CP4135, 19°58.42′ N, 114°32.93′ E to 19°58.94′ N, 114°37.70′ E, 211–218 m, coll. ZHONGSHA 2015 Expedition, 23 Jul. 2015; 1 ovigerous ♀ (11.0 × 6.9 mm) ( ZRC 2016.0073), west of Zhongsha, seamount, stn CP4151, 16°04.72′ N, 113°55.09′ E to 16°02.58′ N, 113°53.93′ E, coll. ZHONGSHA 2015 Expedition, 27 Jul. 2015.

INDONESIA: 1 ♂ (14.0 × 9.0 mm) ( AM P.34658), Kai Island, stn 46, 5°47.20′ S, 132°13′ E, 300 m, coll. Danish Kai Islands Expedition, 2 May 1922.

PHILIPPINES: 1 ♂ (14.9 × 10.2 mm), 1 ♀ with Sacculina (15.5 × 10.4 mm), 1 ♀ (14.0 × 9.2 mm) ( ZRC 2011.0056), northwest coast of Panglao Island, 146–549 m, coll. J. Arbasto, Jan.–Mar. 2011; 2 ♂♂ (13.4 × 8.8 mm, 11.6 × 7.9 mm), 1 ♂ with Sacculina (15.7 × 10.5 mm), 1 ♀ with Sacculina (11.5 × 8.1 mm) ( ZRC 2013.0761), Bohol, off Panglao Island, Balicasag Island, P.K.L. Ng et al. leg., 25–30 Jul. 2003.

Remarks

Oxypleurodon stimpsoni Miers, 1885 , is the type species of the genus. Miers (1885) first mentioned the species in a narrative, followed by a detailed description and figures of the species based on material in the “ Challenger ” expedition, collected from Indonesia and the Philippines in 1886. The first description of the genus and species by Miers (1885) was not known to Tavares (1991), when he revised the genus ( Froglia & Clark 2011: 51). Specimens from Indonesia were measured and figured by Miers (1886: 39, pl. 6 fig. 1). This species appears to be common in the depth range of 250 to 580 m in the tropical West Pacific and Indo-Malayan archipelago. The specimens examined from the South China Sea (SCS) have dorsal plates on carapace with rounded angles, and the articles of the ambulatory legs are cylindrical and slightly carinate ( Figs 2C , 3C ). The large series of specimens from Balicasag Island, the Philippines, differ from the SCS material in several features: the pseudorostral spines are relatively more divergent; the angles of the plates (especially the gastric plate) are sharper; and the articles of the ambulatory legs are more distinctly carinate ( Figs 2B , 3B ). Interestingly, the morphology of the only specimen collected by the AURORA cruise on the east coast of Luzon is closer to the SCS material than those from the Bohol Sea. With regards to the specimen from the Kai Islands in Indonesia, which is closer to the type locality, the dorsal plates look relatively more inflated and the branchial plates are more elongated ( Figs 2A , 3A ) compared to the SCS specimens ( Figs 2C , 3C ); and the meri of the ambulatory legs are also weakly carinate. The variation observed here is difficult to explain and suggests that we are dealing with a species-complex. To resolve this matter, all the available specimens from across its wide range (including the types) will need to be examined. At present, only one species is recognised, O. stimpsoni sensu lato.

Distribution

This species was recorded from Indonesia ( Miers 1885), the Philippines ( Miers 1886; Richer de Forges & Ng 2009), Japan ( Sakai 1938) and South China Sea ( Lee et al. 2015).

Figures

Fig. 2. Oxypleurodon stimpsoni Miers, 1885, overall dorsal view. A. ♂ (14.0 × 9.0 mm) (AM P34658), Indonesia. B. ♂ (14.9 × 10.2 mm) (ZRC 2011.0056), Philippines. C. ♂ (with Sacculina, 14.0 × 9.0 mm) (ZRC 2016.0072), South China Sea. Scale bar = 5 mm.

Fig. 3. Oxypleurodon stimpsoni Miers, 1885, lateral view of carapace. A. ♂ (14.0 × 9.0 mm) (AM P34658), Indonesia. B. ♂ (14.9 × 10.2 mm) (ZRC 2011.0056), Philippines. C. ♂ (14.0 × 9.0 mm) (ZRC 2016.0072), South China Sea. Scale bars = 5 mm.