Strobiligera sp. 1

Figure 22

Material examined. Brazil: off Espírito Santo state: MNHN, MD55 41-DC73 [1].

Description. Shell sinistral, elongated, very thin, almost fusiform, rectilinear profile, reaching 3.19 mm in length, 0.77 mm in width, length/width ratio 4.1. Protoconch slightly globose, subcylindrical, 0.47 mm in length, 0.43 mm in width of its last whorl; 2.75 convex protoconch whorls, weak distinction between protoconch and teleoconch; initial whorl somewhat pointed, mostly smooth, but with several minute, irregular granules especially concentrated on its abapical portion; remaining whorls initially with a strong spiral cord in a median/adapical position of the whorl, assuming an abapical position and a keeled shape; an adapical cord appears soon after, much narrower than the abapical one until the end of protoconch, in addition to a small subsutural thread; the two main cords are situated at 26% and 60% of last whorl height. Teleoconch with up to ~8.5 whorls; three spiral cords in the beginning, continuous to those of protoconch, the adapical one narrower than other cords through the entire teleoconch; on the body whorl, distance between spiral cords is 2.1 times the width of cords; 15 opisthocline axial ribs; rounded nodules of a medium size; distinct suture, with a small sutural cord; narrow, slightly wavy subperipheral cord, one smooth, very narrow basal cord, close to the subperipheral cord; shortened base; no supranumerical cords; ovate aperture, length/width ratio 1.3; anterior canal partly broken; posterior canal not formed. White shell.

Remarks. Strobiligera sp. 1 is similar to shells of S. dinea from Brazil, the differences between them consisting of the width of the teleoconch (1.20 mm in a shell of of S. dinea 3.83 mm in length, 0.77 mm in a shell of Strobiligera sp. 1 3.19 mm in length), the dimensions of the protoconch (first whorl much inflated in S. dinea) and the abapical cord of the protoconch being more prominent in Strobiligera sp. 1 (but the adapical one in S. dinea).

The shell of Strobiligera sp. 1 is also apparently narrower than those of Strobiligera enopla (Dall, 1927) (Fig. 3X) and Strobiligera meteora (Dall, 1927), both from the northwestern Atlantic (Rolán & Fernández-Garcés 2008), in addition to the adapical spiral cord of the teleoconch of Strobiligera sp. 1 being broader than that of S. enopla but narrower than that of S. meteora .

Geographical distribution. Brazil: off Espírito Santo.

Bathymetric distribution. 607–620 m.