Turrids show a diversity of shell shapes, some look like cones, others resemble mitrids, fasciolarids or buccinids. Turrids are carnivorous, some have a radula and associated poison gland similar to the harpoon-like structure of the cone shells, while others have lost the radula and poison gland. Most of the species live deep water area and some occupy shallow subtidal down to 20 m. The primary identification feature of turrids is the sinus, the indentation at the top of the outer lip. Its shape and position are important for classification. The sinus may be narrow and deep, broad and shallow, or a mere indentation as in members of the subfamily Mangelliinae. The apex of the sinus may be on the periphery of the last whorl, at the suture, or on the shoulder slope between suture and periphery. Development of the sinus proceeds as the shell matures, being only a shallow indentation in juvenile shells.
Genus: Gemmula Weinkauff, 1875
Species: Gemmula speciosa Reeve, 1843
Shell length 64.4 mm, moderately thick, cone-spire, cordlet, deep spiral cord, striation, long siphonal canal, white.
Pleurotoma speciosa Reeve, 1842.
Gemmula speciosa Reeve, 1843- [Hinton (1972): 61; Abbott and Dance (1982): 238; Springsteen et al. (1986): 267; Tucker (2004): 922].
Indo West Pacific.
This taxon has not yet been assessed for the IUCN Red List.