Epitonium (Parviscala) deificum ( Melvill & Standen, 1903 )

Brown, Leonard & Raines, Bret, 2004, Two new records of Epitoniidae from Easter Island, Chile, Zootaxa 402 (1), pp. 1-7 : 2-3

Epitonium (Parviscala) deificum ( Melvill & Standen, 1903)

( Figure 1 )

Scala deifica Melvill & Standen, 1903: 343 , pl. VII, fig. 4.

Epitonium deificum ( Melvill & Standen, 1903) : Kaicher, 1980: 2316.

Parviscala deifica ( Melvill & Standen, 1903) : DuShane, 1988: fig. 10; 1990: 8–9, fig. 37–38.

Epitonium (Parviscala) deificum ( Melvill & Standen, 1903) : Weil et al., 1999: 108, fig. 346.

Type material: BMNH type collection: 1903.12.15.19 (one syntype) ( Trew, 1987).

Type locality: Gulf of Oman, 156 fathoms [= 285 m] (by original designation) .

Distribution: Originally described from the Gulf of Oman, but is known from the Red Sea and the Hawaiian Islands ( DuShane, 1990). Now, first reported from Easter Island.

Habitat: In sand and rubble collected at 150 m, off the western coastline from Hanga Pico to Orongo, and from sand collected at 100 m from La Perouse Bay.

Description: White; 3–4 glassy, smooth protoconch whorls, about 8 teleoconch whorls; sutures deep; about 18 thin erect costae that are hooked below the suture, interspaces are spirally striate; about 21 spiral lines on the body whorl, lip reflected with a small hook; maximum size of approximately 11 mm.

Remarks: The complete specimen from Easter Island matches up well with the E. deificum from Mamala Bay, Hawaii, illustrated in DuShane (1990:15, figures 37–38), with the only noticeable difference being the fact that the specimen from Easter Island has 21 costae on the body whorl whereas the Hawaiian specimen appears to have about 16 costae. However, as DuShane (1990) noted, the more costae per whorl, the greater variability there may be. Therefore, we do not consider the difference in the number of costae to be significant. Epitonium deificum ( Melvill & Standen, 1903) , can be distinguished from E. (P.) cf. gloriolum Melvill & Standen reported from Hawaii by DuShane (1990), because the latter species has fewer, thicker, more widely spaced spiral cords on the teleoconch whorls. Epitonium (P.) gradilis ( Jousseaume, 1912) , another species reported from Hawaii by DuShane (1990), has much heavier, strongly reflected costae, not at all like the thin erect costae found on E. deificum . Epitonium deificum is represented from Easter Island by one complete specimen and numerous fragments.

Figures

FIGURE 1. Epitonium (Parviscala) deificum (Melvill & Standen, 1903), length: 3.76 mm. A) Full apertural view. B) Close up of protoconch and postnuclear whorls. C) Close up of costae and sculpture. D) Close up of suture. Scale bars: B, C & D = 250 µm. Photographs by B. Raines.