Cranopsis columbaris, Simone, Luiz Ricardo L. & Cunha, Carlo M., 2014

Simone, Luiz Ricardo L. & Cunha, Carlo M., 2014, Taxonomical study on the mollusks collected in Marion-Dufresne (MD 55) and other expeditions to SE Brazil: the Fissurellidae (Mollusca, Vetigastropoda), Zootaxa 3835 (4), pp. 437-468 : 452

Cranopsis columbaris new species

Figures 84–89

Types. Holotype MZSP 107719. Paratypes: MZSP 105520, 3 shells from type locality.

Type locality. Brazil. Ceará, off Fortaleza, Canopus bank, 2°12’43”S 38°18’52”W, 250 m (Coltro col., viii/ 2005).

Diagnosis. Apex curved posteriorly, dorsal-located. Height 68% of length; width 70% of length. Sculpted by ca. 30 radial, low cords, with rather triangular pustules; interspaces twice cords’ width. Foramen with tall edges; located dorsally.

Description. Shell size up to 2.8 mm; tall, cone-like; height 68% of length. White-translucent, with minute white-opaque pits in interspaces of radial sculpture (Figs 84, 85). Protoconch one rounded whorl (Figs 86, 89); situated on right; smooth, opaque; ca. 170 µm. Foramen cuneiform (pointed anteriorly), width ca. 30% of length; located dorsally, preceding anterior slope; 9% of shell width, 22% of shell length; edges regular, thick (Figs 85, 87), projected dorsally as short wings. Groove anterior to foramen very narrow; flanked by pair of cords similar sized as neighboring cords; length 84% of shell height (Fig. 85, 87). Shell profile conical, apex curved posteriorly, in dorsal quarter of shell height, located between middle and posterior thirds (in dorsal view); teleoconch of 1.2 whorls (Figs 84, 86). Sculpture of ca. 30 radial cords (Figs 84–87, 89), with small, rather triangular pustules (longer axis radially arranged); cords gradually increasing in width towards aperture ( Fig. 89 ); ca. 10 primary cords, in ventral half secondary cords gradually appearing; pustules slightly elevated, scale-like, twice as long as wide, connected with neighboring pustules of same radial line by narrow folds; interspaces between successive radial cords ca.3 times their width; ca. 40 pustules along cords close to median line. Selenizone short, narrow, shallow, anterior part as wide as foramen, 33% of shell length (Figs 85, 87). Aperture planar (Figs 84, 86), outline elliptical, width ca. 70% of length; edges slightly denticulated by radial sculpture. Inner surface smooth, glossy ( Fig. 88 ); narrow furrow located in front of fissure, fainting at short distance from anterior edge (Figs 87, 88). Septum ca. 60% of shell height; ca. 3 times higher than wide; ventral edge somewhat straight, 41% of aperture width ( Fig. 88 ); gradually narrowing up to posterior edge of fissure (Figs 84, 87).

Measurements (in mm). Holotype = 2.8 by 1.9 mm.

Distribution. Continental slope off Ceará, Brazil.

Habitat. Sandy bottoms with debris, 250 m (dead specimens).

Material examined. Types.

Etymology. The specific epithet is derived from Latin columbar-is, meaning collar, an allusion to the shell sculpture, looking like a necklace with radially arranged stones.

Figures

FIGURES 88 – 89: Cranopsis columbaris n. sp., holotype MZSP 107719 (L 2.8 mm), SEM. Fig. 88: ventral-slightly right view. Fig. 89: detail of apical region, right view, scale = 50 µm. FIGURES 90 – 99: Emarginula suspira n. sp. types. Fig. 90: paratype MZSP 102932, dorsal view (L 5.0 mm). Fig. 91: holotype MNHN 25310, right view, detail of apex region (right side = 2 mm). Fig. 92: paratype MNHN 25311 (same as Fig. 98, upper side = 1 mm), ventral view. Fig. 93: holotype, MNHN (sta. 75), dorsal view (L 6.8 mm). Fig. 94: same, right view. Fig. 95: same, ventral view. Fig. 96: paratype MNHN 25311, dorsal view (L 3.9 mm). Fig. 97: same, right view. Fig. 98: same, ventral view. Fig. 99: paratype MNHN 25315 (sta. 34), dorsal view (L 2.7 mm).