Description
Author: Jan Delsing
Text ID: 114058
Text Type: 1
Page: 0
Created: 2022-03-10 14:04:49 - User Delsing Jan
Language: EN
Text function: [[t:1878470,textblock=114058,elang=EN;Description]]
Shell small, solid, circular, lenticular, depressed, nearly flat spire, whitish. Protoconch with 2,25 whorls, small nucleus of 40 µm and a total diameter of about 420 µm Teleoconch with up to two whorls, which have a light insinuation of ribs at the beginning, but immediately smooth except for a small depression near the suture; the periphery is formed by 5 well-marked spiral cords, which are continued towards the base by other, a little more attenuated spiral cords. Suture visible, not deep, bordered by a small depression at each side. Under high magnification one can see numerous microtubercles in the depressed areas between the cords, which in the periphery are replaced by an irregular structure in axial sense. The umbilicus is very wide, so that the previous whorls can be seen. Aperture circular with two expansions, the upper one adherent to the anterior whorl and the lower one prominent towards the base. Dimensions: the holotype measures 1.2 mm, the largest shell measures 1.7 mm. The smooth surface of the dorsum of the shell makes this species stand out from all other Circulus from the West African area.
Rolán E. & Swinnen F. (2013) A new Circulus species (Gastropoda, Rissoidea) from Senegal.
Distribution
Author: Jan Delsing
Text ID: 114059
Text Type: 3
Page: 0
Created: 2022-03-10 14:05:47 - User Delsing Jan
Language: EN
Text function: [[t:1878470,textblock=114059,elang=EN;Distribution]]
Distribution: Only known from the type locality, but with a protoconch consisting of 2 XA whorls it is probable that it has a large range of distribution, but being a species from deep water it is probably difficult to be collected. Type locality: Saint Louis, Dakar, Senegal, at 100-120 m.
Rolán E. & Swinnen F. (2013) A new Circulus species (Gastropoda, Rissoidea) from Senegal.