Opalia revizee, Lima, Silvio Felipe Barbosa & Christoffersen, Martin Lindsey, 2014

Lima, Silvio Felipe Barbosa & Christoffersen, Martin Lindsey, 2014, New species of Gregorioiscala and Opalia (Caenogastropoda: Epitoniidae) in the Western Atlantic: a case of republication, Zootaxa 3835 (3), pp. 392-396 : 394

Opalia revizee n. sp.

Type material. Holotype, MNRJ 18.307 ( Fig. 2 ).

Type locality and distribution. Continental slope of the state of Alagoas (northeastern Brazil), 'Natureza', 10°06'35'' S, 35°46'41'' W, 720 m, 16.xii.2001.

Description. Shell small (3.03 mm long), conical, whitish. Protoconch conical, multispiral, with about 3 slightly convex whorls, sculptured with spiral rows of microscopic pits. Teleoconch with about 5 rounded whorls, regularly convex, surface totally covered by intritacalx thickened, densely and coarsely sculptured with conspicuous spiral rows of microscopic oval pits. Varix prosocline, strong, thick, broad, rounded on penultimate and body whorl. Suture quite impressed, weakly deep. Body whorl prominent, about 1/2 of total length. Base rather broad, weakly convex, without basal ridge and disc. No umbilicus. Aperture oval. Peristome double, thickened, complete.

Etymology. The specific name, revizee , is actually an acronym for "Recursos Vivos na Zona Econômica Exclusiva", which is the program through which the new species were collected on the Brazilian coast.

Remarks. Opalia revizee n. sp. is somewhat similar to O. fortunata Bouchet & Warén, 1986 from the northeastern Atlantic. Both species have small, regular conical shells with a similar outline and number of whorls on the proto/teleoconch. Furthermore, a thickened peristome, microscopic pits and a prominent varix are present on the teleoconch of the new species and O. fortunata .

Despite the surface somewhat eroded, Opalia revizee n. sp. shows clearly a dense intritacalx, which is coarsely sculptured with pits, while the surface of the shell in O. fortunata is very smooth with pits that are not as coarse in comparison to the new species. The body whorl accounts for about 50% the total length in O. revizee n. sp., while reaching about 60% the length of the shell in O. fortunata . The main difference that distinguishes the two species is the low axial ribs on the teleoconch of O. fortunata ( Bouchet & Warén 1986: 552, figs. 1233, 1267; Weil et al. 1999: 44), whereas there is no evidence of axial ribs on the teleoconch whorls of O. revizee n. sp.

Figures

FIGURE 2. Opalia revizee n. sp., holotype, MNRJ 18.307. A, ventral view; B, view of body whorl; C, teleoconch – detail of sculpture; D, protoconch – lateral view; E, protoconch – detail of sculpture. Scale bars: A. 300 µm, B. 200 µm, C – D. 100 µm, E. 20 µm.