Popis
Autor: Jan Delsing
Text ID: 125643
Text Type: 1
Page: 0
Založeno: 08.06.2023 14:56:59 - Uživatel Delsing Jan
Language: EN
Odkazová funkce: [[t:2003373,textblock=125643,elang=EN;Popis]]
Shell rather large, wax yellow. Nuclear whorls decollated, except the last turn which is smooth. Postnuclear whorls almost flattened, slightly shouldered at the summit, marked by strong, rounded, slightly protractile axial ribs, which are interrupted by a deep spiral sulcus at the anterior extremity of the posterior two-thirds of the ribs, which lends them the appearance of so many exclamation points. Of these ribs, 16 occur upon the first to third, 18 upon the fourth, 20 upon the fifth, 22 upon the sixth and seventh, and 20 upon the remaining whorls. The ribs are abruptly truncated at the anterior termination of the sulcus and slopingly so at the posterior. In addition to the above sculpture, there appears in (he suture of each turn, an almost smooth, strong spiral cord, which on the last turn, forms the peripheral cord, to which the axial ribs extend feebly. Base very short, slightly concave, marked by three equal and equally spaced spiral cords which occupy the space between the peripheral cord and the insertion of the columella. The spaces which separate these cords are a little less wide than the cords. Aperture decidedly channeled anteriorly and loss strongly so posteriorly; outer lip rendered sinuous by the external sculpture, translucent, showing the external sculpture within; columella covered by a thick callus which is reflected over the parietal wall and renders the peritreme complete.
The type, Cat. No. 250350, U.S.N.M., comes from Port Alfred (Coll. No. 1223). It has 11,5 whorls and measures: Length, 12 mm.; diameter, 3.5 mm.
Bartsch, P., 1915. Report on the Turton Collection of South African marine mollusks, with additional notes on other South African shells contained in the United States National Museum.