Calliostoma hassler Clench & Aguayo, 1939

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 : 404

Calliostoma hassler Clench & Aguayo, 1939

( Fig. 2 A–G)

Synonymy see Dornellas & Simone (2013). Complement:

Calliostoma hassler Clench & Aguayo, 1939: 191 , pl. 28, fig. 3; Abbott, 1974: 46; Massemin et al., 2009: 84, pl. p83; Dornellas, 2012: 104, figs 13–15; Dornellas & Simone, 2013: 285, figs 24–25, 44, 51–53, 91–98.

Astele (Leiotrochus) hassler: Macsotay & Campos, 2001: 35 , pl. 13, figs 9–10.

Calliostoma sp.: Longo et al., 2014: 2, fig. 4F.

Type material. Holotype: MCZ 104554 . Paratypes: MCZ 104555 , 1 sh ; MFP, 1 sh; all from type locality.

Type locality. Brazil, off Cabo Frio , 75 miles east of Rio de Janeiro, 64 m (20/ii/1872) .

Distribution. From Paria, northern Venezuela, to southeastern Brazil, live specimens from 20–100 m ( Macsotay & Campos 2001; Dornellas & Simone 2013).

Habitat. On bottoms alongside bryozoans and coralline algae ( Clench & Turner, 1960).

Material examined. Brazil: Espírito Santo: off São Mateus, Jaseur Bank, 20°27’S, 35°54’W, MD55 sta. DC34, 54 m, MNHN, 1 sh (15/v/1987); Vitoria Bank , 20°32’S, 38°10’W, MD55 sta. DC 22, 52 m, MNHN, 1 sh; Davis Bank , 20°39’S, 34°41’W, MD55 sta. DC40, 60 m, MNHN, 1 sh; Columbia Bank , 20°41’S, 32°12’W, MD55 sta. DC47, 94– 105 m, MNHN, 2 sh (19/v/1987); Dogaressa Bank, 20°54’S, 34°01’W, MD55 sta. DC42, 60 m, MNHN, 1 sh (17/v/1987); Rio de Janeiro: off Cabo de São Tomé, 21°37’S, 40°18’W, MD55 sta. DC15, 37 m, MNHN, 7 sh (10/v/1987). Additional non-MD55 material : Brazil: Rio de Janeiro: types .

Measurements. 7¾ whorls, H= 25.8 mm, D= 25.7 mm (largest whole specimen).

Remarks. The single well-preserved adult individual from the MD55 assemblage ( Fig. 2 A–B) is remarkably similar to the type specimens in outline, sculpture, and coloration. In the original description, Clench & Aguayo (1939) emphasized the yellowish hue of the types owing to a probable color loss after extended exposure to preservative fluid. However, the material studied herein, as well as the specimens illustrated by Dornellas & Simone (2013), suggest otherwise: the variation in color from yellowish ( Fig. 2 A–B) to strongly red ( Fig. 2 D ) seems to be the normal color range of this species. Moreover, even though most specimens have a homogeneous coloration, except for some faint, darker colored axial stripes and white blotches ( Fig. 2 D–F), some have a mixed coloration, showing a reddish-orange hue on the first whorls that becomes yellowish towards the body whorl ( Fig. 2 A ). The protoconch ( Fig. 2 G ), however, seems to be invariably ivory white. The record from the MD55 sta. CB77 is the deepest known so far, though it consists of an empty, fragmentary shell.

There is a large conchological overlap between C. hassler and C. jujubinum ( Gmelin, 1791) , a species known from Mexico and the Caribbean. Wide-ranging calliostomatid species are not entirely uncommon ( Clench & Turner 1960), and a possible synonymy between these two should be further analyzed. Massemin et al. (2009) reported both species occurring together in French Guyana.

Figures

FIGURE 2. Calliostoma collected by the MD55 expedition. A–G. Calliostoma hassler. A. MNHN, sta. DC47, apertural view (H=25.8 mm, D=25.7 mm). B. same, umbilical view. C. MNHN, sta. DC15, apertural view (H=10.2 mm, D=11.1 mm). D. MNHN, sta. DC40, juvenile specimen, apertural view (H=9.6 mm, D=12.2 mm). E. MNHN, sta. DC42, apertural view (H=3.6 mm, D=4.4 mm). F. MNHN, sta. DC22, apertural view (H=1.4 mm, D=1.8 mm). G. MNHN, sta. DC42 detail of apex. H–L. Calliostoma javanicum. H. MNHN, sta. DC55, juvenile specimen, apertural view (H=5.4 mm, D=5.5 mm). I. MNHN, sta. CB77, fragmentary specimen (H=~5.0 mm, D=~4.7 mm). J. MNHN, sta. DC55, juvenile specimen, detail of apex. K. same, apical view. L. same, umbilical view.