Speocarcinus spinicarpus Guinot, 1969

Brandão, Marianna, Coelho-Filho, Petronio Alves & Tavares, Marcos, 2012, A review of the genus Speocarcinus Stimpson, 1859 (Crustacea: Brachyura: Xanthidae), with a key to its species and the description of one new species, Zootaxa 3327, pp. 1-19 : 16

Speocarcinus spinicarpus Guinot, 1969

( Fig. 2 H; 6F; 7 F–G; 8D; 9 C–D)

Speocarcinus spinicarpus Guinot, 1969: 711 .

Speocarcinus spinicarpus —Ng et al. 2008: 201; Brandão et al. 2010: 137.

Material examined. Holotype, male cl 16 mm, cw 19 mm ( USNM 231701), Mexico, Gulf of California, C. Walker, coll. ii.1949, 9– 18 m. Baja California, 10 miles southeast of San Felipe, 18 m: 2 males, 2 females paratypes ( USNM 125076).

Type locality. Gulf of California, Sonora, Mexico, between 9 and 18 m.

Description. See Guinot (1969).

Remarks. Speocarcinus spinicarpus mostly resembles S. granulimanus in several features, including the shape and ornamentation of the carapace; the shape, coalescence and number of anterolateral teeth of the carapace; and the presence of a strong spine on the inner margin of the cheliped carpus. However, the two species are clearly distinct from one another primarily in features of the propodus and carpus of the cheliped, and the male abdominal segment 6 and telson. In S. spinicarpus the cheliped propodus is generally smooth, except for a row of granules along the proximal part of its inferior margin ( Fig. 2 F), whereas in S. granulimanus the cheliped propodus has a row of granules extending longitudinally across its dorsal and ventral margins, and its lateral surface is microscopically granular and coarsely granular posteriorly ( Fig. 2B ). In S. spinicarpus , the dorsal surface of the cheliped carpus is smooth, except for small granules lining the margins and scattered, minute granules near the inner margin ( Fig. 9C ), whereas in S. granulimanus it is evenly coarsely granular ( Fig. 9A ). The anterolateral angles of the abdominal segment 6 are strongly produced outward and the telson is broadly triangular in S. spinicarpus ( Fig. 9 D), whereas in S. granulimanus the anterolateral angles of the abdominal segment 6 are weakly produced outward and the telson is distinctly more elongated ( Fig. 9B ).

Distribution. Mexico, Gulf of California, 9 to 73 m.

Figures

FIGURE 2. A – B, Lateral view of right and left chelipeds, respectively. C – H, Habitus, dorsal view. A, C, Speocarcinus amazonicus Brandão, Tavares & Coelho-Filho, 2010, holotype male cl 8 mm, cw 11 mm (MZUSP 23654). B, D, Speocarcinus granulimanus Rathbun, 1894, lectotype male cl 17.5 mm, cw 21 mm (USNM 17461). E, Speocarcinus lobatus Guinot, 1969, holotype male cl 16 mm, cw 12 mm (USNM 101081). F, Speocarcinus meloi D’Incao & Silva, 1991, holotype male cl 12 mm, cw 15.6 mm (MZUSP 9577). G, Speocarcinus monotuberculatus Felder & Rabalais, 1986, holotype female cl 6 mm, cw 7.8 mm (USNM 228459). H, Speocarcinus spinicarpus Guinot, 1969, male holotype cl 16 mm, cw 19 mm (USNM 231701). Note the differences in the chelipeds inner carpal spines. Scale bars: C – F, H, 10 mm; G, 2.5 mm.

FIGURE 9. A, C, Carpus of the right cheliped in dorsal view. B, D, Telson and sixth abdominal segment in dorsal view. A – B, Speocarcinus granulimanus Rathbun, 1894, lectotype male cl 17.5 mm, cw 21 mm (USNM 17461). C – D, Speocarcinus spinicarpus Guinot, 1969, male holotype cl 16 mm, cw 19 mm (USNM 231701). Scale bars: A – D, 1 mm.