Synalpheus cf. pandionis Coutière, 1909

Almeida, Alexandre Oliveira De, Guerrazzi, Maria Cec Lia & Coelho, Petr Ȏ Nio Alves, 2007, Stomatopod and decapod crustaceans from Camamu Bay, state of Bahia, Brazil, Zootaxa 1553, pp. 1-45 : 15

Synalpheus cf. pandionis Coutière, 1909

( Figs. 3–4 )

Material examined (N=2). 1f, 24/III/2005, St. 0 4 ( MZUESC #661); 1f, 30/X/2004, St. 0 4 ( MZUESC #709).

Distribution. Western Atlantic – Florida, Gulf of Mexico, Puerto Rico, Virgin Islands, Barbados, Curaçao, off Panama, and Venezuela ( Chace 1972; Dardeau 1984). Brazil (Ceará) ( Coelho Filho 2006).

Ecological notes. Under rocks, in seagrass meadows, sponges, and dead and living coral. From shallow waters to 73 m ( Dardeau 1984).

Previous records in Bahia. None.

Remarks. Synalpheus pandionis is a western Atlantic species complex within the S. longicarpus (Herrick, 1891) clade (see Morrison et al. 2004).

Dardeau (1984) resurrected S. pandionis from the synonymy of S. longicarpus , originally proposed by Christoffersen (1979). The morphology of two females (MZUESC#661: 4.0 mm CL, not ovigerous; MZUESC#709: 4.7 mm CL, ovigerous) examined by us agrees well with the diagnosis of S. pandionis provided by Dardeau (1984). The orbital hoods and the rostrum are subequal in length; they are also rounded and broader than the rostrum; the space between the orbital teeth and the rostrum is U-shaped ( Figs. 3 A, B). The antennal scaphocerite and basicerite are subequal in length ( Fig. 3 A). The palm of the major chela bears a blunt dorsodistal tubercle, which is armed with a secondary, ventrally directed tooth ( Figs. 3 H, I). The dactylus of the minor first chela is distally bidentate; the fixed finger is simple ( Fig. 4 C). The pereiopods 2–5 are very similar to those illustrated by Dardeau (1984) ( Figs. 4 D, E, G, I). The uropodal exopod is armed with 5 fixed teeth proximal to the movable spine ( Fig. 3 F). The dactyli of pereiopods 3–5 are biunguiculate, with the tooth on the flexor margin being smaller and slightly divergent from the distal tooth ( Figs. 4 F, H, J). The main difference between the two females examined by us lies in the rostrum length. A subtle variation was observed in the length of the rostrum relative to the orbital hoods length: in the ovigerous female (MZUESC#709), the rostrum is narrower at base (spine-like in dorsal view) and slightly longer than the orbital hoods ( Fig. 3 B), whereas in the non-ovigerous female (MZUESC#661), the rostrum and orbital hoods are equal in length and the rostrum has a wider base (more triangular) ( Fig. 3 A). The herein reported occurrence of S. cf. pandionis in Camamu Bay extends the southern range limit of this species complex.

Figures

FIGURE 3. Synalpheus cf. pandionis Coutière, 1909, from Camamu Bay, Bahia, Brazil. A, D – F, H, I: non-ovigerous female (MZUESC # 661); B, C, G, ovigerous female (MZUESC # 709). A. anterior region of carapace and frontal appendages, dorsal view; B. anterior region of carapace, dorsal view; C. same, lateral view; D. abdomen and telson, lateral view; E. telson, dorsal view; F. uropod, left exopod, dorsal view; G. left major chela, lateral view; H. left major chela, lateral view of distal portion; I. same, mesial view; Figures A, C, E – G — setae omitted. Scale bars: A, C, D, H, I = 1 mm; B, E, F = 0.5 mm; G = 2 mm.

FIGURE 4. Synalpheus cf. pandionis Coutière, 1909, ovigerous female (MZUESC # 709), from Camamu Bay, Bahia, Brazil. A. right minor chela, lateral view; B. same, dorsal view; C. same, detail of chela, mesial view. D. right pereiopod 2; E. right pereiopod 3; F. same, distal portion; G. right pereiopod 4; H. same, distal portion; I. right pereiopod 5; J. same, distal portion. Scale bars: A, B, D, E, G, I = 1 mm; C = 0.5 mm; F, H, J = 0.25 mm.