Zeidora pussa, 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 : 460-461

Zeidora pussa new species

Figures 126–132

Types. Holotype MNHN 25320. Paratypes: MZSP 107728, 1 shell from type locality. Brazil. Espírito Santo, continental slope of Abrolhos (MD55; Bouchet, Leal & Métivier col, 27/v/1987); off Regência, 19°40’S 37°48’W, 790–940 m, MNHN 25880, 1 shell, MZSP 105511, 1 shell (sta. CB77); off Itaúnas, 18°59’S 37°48’W, 607–620 m, MNHN 25321, 1 shell (sta. DC73); 18°59’S 37°50’W, 295 m, MZSP 105510, 2 shells (sta. DC75).

Type locality. Brazil. Espírito Santo; off Conceição da Barra, continental slope of Abrolhos, 18°59’S 37°50’W, 637 m (MD55 sta. CB76; Bouchet, Leal & Métivier col. 27/v/1987).

Diagnosis. Shell symmetrical to slightly curved to left. Height ca. 40% of length; width 62% of length. Sculpted by ca. 60 radial, low cords, and concentric cords of equal size, forming delicate, but well-marked network, interspaces ca. 5 times cords’ width. Slit relatively wide, 28% of shell length. Septum ca. 30% of shell length.

Description. Shell size ca. 4 mm; low, elongated, limpet-like; height ca. 40% of length. Pure white. Protoconch sunken in posterior shell wall (Figs 127, 128, 132), of one rounded whorls; in median line, slightly bended to right; size 280 µm. Slit rectangular, widely opened anteriorly, posterior end rounded, ca. 15% wider than long; ca. 8% of shell width, 28% of shell length; edges simple, rather irregular (Figs 126–128, 130, 132). Apex terminal, slightly protruding posterior end of shell, in median region; teleoconch of 1.5 whorls; sagittal profile as arc (imaginary center of arc located in middle level of ventral surface, ca. 20% below aperture) (Figs 129, 131). Sculpture of narrow, equally developed radial and concentric cords (Figs 126, 129, 130, 131), forming delicate network, ca. 60 radial cords close to shell edge, ca. 40 concentric cords close to median line; cords with approximately same width from apical region to shell edge, secondary cords gradually appearing (Figs 126, 130); interspaces between radial cords ca. 5 times cord’s width, concentric cords with interspaces slightly longer than radial interspaces. Selenizone long, running all along shell median line (except for slit), anteriorly as wide as slit, shallow; edges simple, low, similar to neighboring radial cords; lunules regularly distributed and well-spaced (Figs 126, 130). Aperture planar (Figs 128–129, 131), outline elliptical, width 62% of length; edges simple. Inner surface smooth, glossy (Figs 127, 128, 132). Septum straight, ca. 30% of shell length; ca. twice as high as wide; anterior edge strongly concave, ca. 80% of aperture width; gradually narrowing to posterior edge, forming ventral wall of posterior cavity for visceral mass (Figs 127, 128, 132). Shell edges exceeding ca. 10% shell width surrounding septum, bearing regular denticulate holes, i.e., ca. 10 pairs of transverse minute teeth (Figs 127, 128, 132).

Measurements (in mm). Holotype: 2.7 by 1.1; Paratype MZSP 105510: 3.9 by 1.5 ( Figs 130–132 ).

Distribution. Continental slope off Espírito Santo, Brazil.

Habitat. Sandy mud bottoms, 607–940 m (dead specimen).

Material examined. Types.

Etymology. The specific epithet is derived from the native Tupy language, puçá (with pronunciation: pussah), meaning a small net for capturing fishes; an allusion to the delicate reticulate sculpture of the shell. The changing of the “ç” for “ss” is for phonetic reasons.

Figures

FIGURES 130 – 132: Zeidora pussa n. sp., paratype MZSP 105510 (L 3.9 mm). Fig. 130: dorsal view. Fig. 131: left view. Fig. 132: ventral view. FIGURES 133 – 134: Zeidora crepidula n. sp., holotype MNHN 25322 (L 4.9 mm). Fig. 133: dorsal view. Fig. 134: ventral view. FIGURES 135 – 139: Emarginula icosisculpta n. sp. Fig. 135: holotype MNHN 25323 (L 2.5 mm), dorsal view. Fig. 136: same, left view. Fig. 137: same, ventral view. Fig. 138: paratype MZSP 102949 (L 2.2 mm), dorsal view. Fig. 139: right view. FIGURES 140 – 143: Hemimarginula hemitoma n. sp.. Fig. 140: holotype MNHN 25324 (L 4.6 mm), dorsal view. Fig. 141: same, right view. Fig. 142: same, ventral view. Fig. 143: paratype MNHN 25326 (L 2.7 mm), dorsal view.