Calliostoma rude Quinn, 1992

Cavallari, Daniel C., Salvador, Rodrigo B., Dornellas, Ana P. S. & Simone, Luiz R. L., 2019, Calliostomatidae, Colloniidae, Margaritidae, and Solariellidae (Gastropoda: Trochoidea) collected by the Marion Dufresne (MD 55) expedition in southeastern Brazil, with description of a new species of Calliostoma, Zootaxa 4609 (3), pp. 401-428 : 407

Calliostoma rude Quinn, 1992

( Fig. 3 A–I)

Calliostoma rude Quinn, 1992: 83 , figs 7–8; Massemin et al., 2009: 85.

Type material. Holotype: USNM 860251 . Paratypes: UMML 305844 , 2 sh, FSBC I 44076, 1 sh, from type locality; MCZ 302593, Guyana, off Georgetown , Chain Cruise 35, sta. 35 and 36, 8°10.5–8°10N, 57°48’W, 53–60 m (28/iv/1963) .

Type locality. French Guyana, off Cayenne, Pillsbury sta. P-650, 6°07’N, 52°19’W, 84–91 m.

Previously known distribution. Guyana to French Guyana, live specimens from 53–91 m ( Quinn 1992).

New occurrence. Southeastern Brazil, off Espírito Santo, Abrolhos Slope, 120–295 m (shells only).

Habitat. Sandy bottoms, 53– 91 m.

Material examined. Brazil: Espírito Santo: off São Mateus, edge of the Abrolhos Slope, 18°59’S, 37°50’W, MD55 sta. DC 75, 295 m, MNHN, 1 sh (27/v/1987); 19°00’S, 37°47’W, MD55 sta. DC81, 120– 135 m, MNHN, 1 sh (27/v/1987). Additional non-MD55 material: French Guyana: holotype.

Measurements. 9 whorls, H= 13.1 mm, D= 9.2 mm (adult specimen).

Remarks. The adult specimen analyzed herein ( Fig. 3 A–C) compares exceedingly well with the holotype, presenting nearly identical proportions, color, and sculpture. Shells of juvenile individuals ( Fig. 3 D–I) have a somewhat flatter base, which also lacks the stronger sculpture of spiral ribs ( Fig. 3 F ) seen in adult individuals ( Fig. 3 C ). The new records reported here are the second since the original description of this apparently rare species. The new occurrence is far away from the previously known distribution in northern South America, extending its range ca. 3,200 km to southeastern Brazil.

Figures

FIGURE 3. Calliostoma collected by the MD55 expedition, Calliostoma rude. A–C. MNHN, sta. DC81 (H=13.1 mm, D=9.2 mm). A. apetural view. B. apical view. C. umbilical view. D–I. MNHN, sta. DC75, juvenile specimen (H=5.0 mm, D=4.5 mm). D. apertural view. E. apical view. F. umbilical view. G. SEM, apertural view. H. SEM, apical view. I. SEM, detail of apex.