Episiphon didymum (Watson, 1879)

Fig. 57

+ Dentalium didymum Watson 1879: 517; 1886: 10, pl. 1, fig. 11.

+ Dentalium ensiculus var. didymum: Pilsbry and Sharp 1897: 123, pl. 7, fig. 20.

+ Dentalium (Bathoxiphus) didymum: Henderson 1920: 83, pl. 14, fig. 10; Maury 1922: 39; Turner 1955: 314.

+ Dentalium (Episiphon) johnsoni Emerson 1952: 5, pl. 1, fig. 2; Penna­Neme 1974: 114.

+ Episiphon didymum: Scarabino 1985: 200, pl. 73, fig. 1024; 1994: 308, pl. 107, fig. 1512; Díaz and Puyana 1994: 257, pl. 71, fig. 1044; Steiner and Kabat 2001: 444; 2004: 584.

+ Episiphon didymus: Redfern 2001: 190, pl. 76, figs. 782a, 782b.

Type material

Syntypes BMNH 1887.2.9.43–44, 2 dd.

Type locality

off Culebra Island, Challenger sta 24, 18 º38’30"N, 65º05’30"W, 712 m (by original designation).

Diagnosis

Shell to 10 mm long, slender, solid, almost straight, yellow­white, smooth, glossy. Apical, oral diameters nearly equal. Apical callous present, non­centric, lumen small. An extended pipe often present. Section subtriangular to suboval throughout.

Material examined

IBUFRJ 14310, sta C13, 1 dd.

Distribution

Caribbean Sea: South Dry Tortugas (Turner 1955); Porto Rico (Emerson 1952); Barbados (Henderson 1920); North of St. Thomas, Virgin Islands (Emerson 1952), off Culebra Island (Watson 1879; Emerson 1952); Colombia (Díaz & Puyana 1994); Bahamas (Redfern 2001); Brazil: off Amapá and Maranhão (Penna­Neme 1974; Scarabino 1985, 1994), Bahia (this study). Living 439 m (Emerson 1952), shells 60 to 830 m (Emerson 1952; Penna­Neme 1974).

Remarks

Emerson (1952) stated that mature specimens range from 17 to 28 mm long, with the Brazilian specimen being shorter. The shell illustrated by Abbott (1974: 387, fig. 4525) as Dentalium (Bathoxiphus) didymum do not fit to this species, being notably more curved.