Heterocithara rigorata facts for kids
Quick facts for kidsHeterocithara rigorata
|Original image of a shell of Heterocithara rigorata|
Mangelia rigorata Hedley, 1909 (original combination)
The length of the shell attains 3.8 mm, its diameter 1.5 mm.
(Original description) The small, oblong shell is turreted and rather solid. Its colour is dull white. It contains 6 whorls, including a smooth three-whorled protoconch. whose initial whorl is eccentric. The sculpture shows from ten to twelve very prominent, close, radial ribs, widest apart on the back of the body whorl, and becoming closer on the earlier whorls. These ribs project on the summit of the whorl and fade gradually on the base. The body whorl is encircled by twelve to fourteen strong spiral cords, which override both ribs and interstices. On the penultimate whorl there are four such cords, and on the antepenultimate three. Between and parallel to the spiral cords are fine, close, microscopic hairlines. The aperture is narrow linear, with a deep sinus and a prominent varix
Some variation in contour occurs, some individuals being shorter and broader than others. The species is characterised by its straight, narrow form, gradate spire, and strongly modelled sculpture.
Heterocithara rigorata Facts for Kids. Kiddle Encyclopedia.