Speocarcinus carolinensis Stimpson, 1859

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 : 6-10

Speocarcinus carolinensis Stimpson, 1859

( Figs. 1A–B ; 3B; 4A, D; 5B; 6B; 8B)

Speocarcinus carolinensis Stimpson, 1859: 59 .

Speocarcinus carolinensis – Faxon 1895: 236; Rathbun 1901: 11; 1918: 39; Tesch 1918: 46; Holthuis 1959: 235; Serène 1964: 194; Guinot 1969: 707; Felder 1973: 71; Powers 1977: 116; Herbst et al. 1978: 993; Williams 1984: 437; Camp et al. 1998: 148; Ng et al. 2008: 201; Brandão et al. 2010: 137.

Material examined. United States, North Carolina, Eastward, st. E2–77–259, 35 °02’24” S–075°W, vi.1977, G. Herbst det.: 1 male cl 10 mm, cw 14 mm ( USNM 180101), st. E2–77–253, 35 °02’18” S–075°W, vi.1977, G. Herbst det.: 1 female cl 8 mm, cw 10.8 mm ( USNM 180100), st. E2–77–257, 35 °03’30” N– 075°25’42”W, 14.viii. 1977, 36 m, 1 female ( USNM 180098) (G. Herbst det.), st. E 5–77–13, 34°34’54” S – 075°10’30”W, 4.viii. 1977, 34 m, G. Herbst det.: 1 female cl 8 mm, cw 10.5 mm ( USNM 180099). Florida, near Crescent Beach, 29o45’30”N – 0 81o 14’25”W, P. Webster coll., 26.v. 1991, 7 m, A.W. Williams det.: 1 male cl 2.9 mm, cw 3.9 mm ( USNM 251311). Florida, Dry Tortuga I., st. 9–31, W. Schmitt coll., 21.vi.1931: 2 juv. males ( USNM 71011).

Puerto Rico, 18o30’24”N – 66o4’15”W, Johnson-Smithsonian Exp. coll., st. 10, 2.ii. 1933, 182 m: 1 juv. male ( USNM 67779). Off Porto Real, Fish Hawk US. Fish Commission, st. 146 (6074), 15 m: 1 juv. male, 1 juv. female ( USNM 23766).

Suriname, R/V Coquette USFWS, st. 212, 14.vi.1957, mud, 43 m, L.B. Holthuis det.: 1 juv. female ( USNM 103293).

Type locality. Charleston Harbor, South Carolina, USA.

Description. See Williams (1984).

Remarks. Large and small individuals of S. carolinensis look very different from each other. In large individuals the carapace anterolateral teeth are remarkably stronger and much more pronounced than in smaller ones, in which the last anterolateral tooth may even be no more than a prominent granule ( Fig. 1A, B ). Small and medium size individuals of S. carolinensis and S. lobatus are very similar in respect to the carapace anterolateral teeth ( Figs.

1B; 2C. See also Felder & Rabalais, 1986). Speocarcinus carolinensis , however, can be separated from S. lobatus by (i) the branchiostegal region of the carapace with dispersed distinct granules, but no transversal row of granules ( Fig. 3B ) (one distinct transversal row of granules in S. lobatus , Fig. 3D ); (ii) the ocular peduncle is smooth ( Fig. 4A ) (ocular peduncle distinctly granular in S. lobatus ); (iii) male abdominal segment 2 free, not intercalated between edges of abdominal segments 3–5 ( Fig. 6B ) (male abdominal segment 2 partially intercalated between edges of abdominal segments 3–5 in S. lobatus , fig. 6D).

Small male and female individuals of S. carolinensis also closely resemble S. monotuberculatus , from which they can be separated by the absence of a dorsal median tubercle on abdominal segment 2, whereas in S. monotuberculatus the male and female abdominal segment 2 has one dorsal median tubercle ( Felder & Rabalais 1986).

Distribution. North Carolina (south of Cape Hatteras) to the Gulf of Mexico and the West Indies, between 15 and 43 m deep.

Figures

FIGURE 1. A – B, D, E, Habitus, dorsal view. C, Lateral view of right cheliped. A – B, Speocarcinus carolinensis Stimpson, 1859. A, adult male cl 29 mm, cw 39 mm (USNM 251311). B, young male cl 10 mm, cw 14 mm (USNM 180101). C – E, Speocarcinus dentatus n. sp. C – D, Adult male holotype cl 11.5 mm, cw 22.5 mm (MZUSP 12615). E, Young male paratype cl 9 mm, cw 17 mm (MZUSP 11007). Note the variation in the patterns in carapace dentition between adult and young individuals. Scale bars: A – B, D, 10 mm; C, E, 2 mm.

FIGURE 3. A – D, Carapace, lateral view. A, Speocarcinus amazonicus Brandão, Tavares & Coelho-Filho, 2010, holotype male cl 8 mm, cw 11 mm (MZUSP 23654). B, Speocarcinus carolinensis Stimpson, 1859, male cl 10 mm, cw 14 mm (USNM 180101). C, Speocarcinus dentatus n. sp., male holotype cl 11.5 mm, cw 22.5 mm (MZUSP 12615). D, Speocarcinus lobatus Guinot, 1969, male cl 5 mm, cw 10 mm (USNM 187191). E – F, Carapace, fronto-lateral view. E, Speocarcinus amazonicus Brandão, Tavares & Coelho-Filho, 2010, holotype male cl 8 mm, cw 11 mm (MZUSP 23654). F, Speocarcinus meloi D’Incao & Silva, 1991, holotype male cl 12 mm, cw 15.6 mm (MZUSP 9577). Note the differences in the granulation pattern on the branchiostegal region. Scale bars: A, D – F, 5 mm; B, 2.5 mm; C, 2 mm.

FIGURE 4. A – B, Carapace, orbital region. C – E, Carapace, dorsal view of fronto-orbital region. A, D, Speocarcinus carolinensis Stimpson, 1859, male cl 10 mm, cw 14 mm (USNM 180101). B, E, Speocarcinus dentatus n. sp., male holotype cl 11.5 mm, cw 22.5 mm (MZUSP 12615). C, Speocarcinus amazonicus Brandão, Tavares & Coelho-Filho, 2010, holotype male cl 8 mm, cw 11 mm (MZUSP 23654). Note the differences in the granulation pattern on the ocular peduncle and on the frontal region of the carapace. Scale bars: A – B, E 2 mm; C – D, 5 mm.

FIGURE 6. A – F, Abdominal segments 1 – 5, ventro-posterior view. A, Speocarcinus amazonicus Brandão, Tavares & Coelho- Filho, 2010, holotype male cl 8 mm, cw 11 mm (MZUSP 23654). B, Speocarcinus carolinensis Stimpson, 1859, male cl 10 mm, cw 14 mm (USNM 180101). C, Speocarcinus dentatus n. sp., male holotype cl 11.5 mm, cw 22.5 mm (MZUSP 12615). D, Speocarcinus lobatus Guinot, 1969, male cl 5 mm, cw 10 mm (USNM 187191). E, Speocarcinus meloi D’Incao & Silva, 1991, holotype male cl 12 mm, cw 15.6 mm (MZUSP 9577). F, Speocarcinus spinicarpus Guinot, 1969, male cl 7 mm, cw 14 mm (USNM 127056). Note in C – D the abdominal segment 2 partially intercalated between edges of the abdominal segments 3 – 5. a 2, abdominal segment 2; a 3 – 5 abdominal segments 3 to 5 fused. St. 6 – 8, thoracic sternites 6 to 8. Scale bars: A – F, 2 mm.