Bathymophila euspira ( Dall, 1881 )

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 : 418

Bathymophila euspira ( Dall, 1881)

( Fig. 7 G–L)

Synonymy see Quinn (1979). Complement:

Margarita euspira Dall, 1881: 44 .

Trochus euspira: Jeffreys, 1883: 98 , pl. 20, figs 6, 6a, 6b.

Margarites (Bathymophila) euspira: Quinn, 1979: 5 , figs 1–2.

Bathymophila euspira: Marshall, 1999: 20 .

Margarites euspira: Rosenberg et al., 2009: 624 ; Welch, 2010: table S1.

Margarites euspirus: Miloslavich et al., 2010 : table S6.

Type material. Unknown ( Quinn 1979).

Type locality. Cuba, off Havana, Blake sta. 2, 23º14’N, 82º25’W, 1472 m .

Previously known distribution. Portugal, Gulf of Mexico, Caribbean Sea, live specimens from 713–1472 m ( Rosenberg et al., 2009).

New occurrence. Southwestern Atlantic, Brazil, off Espírito Santo, Abrolhos Slope.

Habitat. Coralline and muddy bottoms.

Material examined. Brazil: Espírito Santo: off São Mateus, Abrolhos Slope , 19°00’S, 37°48’W, 950–1050 m, MNHN, 2 sh; 19°40’S, 37°48’W, MD55 sta. CB77 , 790– 940 m, MNHN, 1 sh (27/v/1987) .

Measurements. 4½ whorls, H=4.0 mm, D= 4.1 mm (largest specimen).

Remarks. The diagnostic spiral sculpture pattern of the early whorls, as well as the overall shell shape and proportions and the large circular aperture, is consistent with Bathymophila euspira . The holotype of this species could not be located. However, topotypes and the syntypes of the variety (and synonym) B. euspira nitens Dall, 1881 (USNM 214275, from off Portugal), alongside the redescription of Quinn (1979), support the identification of the present specimens. Bathymophila euspira is known for its considerable conchological variation, from completely smooth specimens to a variable number of fine spiral striae and having a subsutural spiny spiral thread ( Quinn 1979). The present specimens lack the subsutural spiral thread and are almost completely smooth ( Fig. 7 G, J ), counting with circa 8 very fine spiral striae on the base of the whorl, circling the umbilicus ( Fig. 7 I, J ). Moreover, the present specimens have narrower shells than the typical B. euspira . The present record greatly extends the species range ca. 6,900 km to the southeast, which is relatively common for the MD55 material (e.g., Calliostoma echinatum , above).

Figures

FIGURE 7. Margaritidae and Solariellidae collected by the MD55 expedition. A–F. Margarites imperialis A–C. MNHN, sta. CB105, spm #1 (H=8.8 mm, D=11.7 mm). A. apertural view. B. apical view. C. umbilical view. D. MNHN, sta. CB105, spm #2 (H=8.6 mm, D=11.2 mm), apertural view. E. MNHN, sta. CB78, juvenile specimen (H=5.5 mm, D=6.6 mm), apertural view. F. MNHN, sta. CB93, juvenile specimen (H=4.3 mm, D=5.2 mm), apertural view. G–L. Bathymophila euspira. G–H. MNHN, sta. DC72 (H=4.0 mm, D=4.1 mm). G. apertural view. H. apical view. I. MNHN, sta. CB77 (D=3.2 mm), umbilical view. J–L. MNHN, sta. DC72 under SEM. J. apertural view. K. apical view. L. detail of apex.