Emperor Helmet Snail

Lamarck, 1822

Cassis madagascariensis

Class:

Order:

Family:

Gastropoda

Littorinimorpha

Cassidae

Cassidae

Shell Information

Maximum length (mm): 350

Dextral

Chirality:

The is a large shell that has a very reduced spire and an enlarged body whorl. This shell typically has three rows of blunt knobs and smaller lines of spiral folds. It has an elongated aperture with folds on both sides of the inner aperture. A dark brown stain will develop between the folds of the inner aperture. Adults develop a thick flattened lip. This shell can vary in color from white to tan and sometimes has brown markings and blotches.

Description:

Ecological Information

Distribution:

Depth (m):

North Carolina to Barbados

3 to 183 meters

Diet:

Carnivore; They feed on a variety seaurchins.

Habitat:

Marine; Soft substrate and among seagrass

Misc. Facts

This is the largest helmet shell found on the east coast of the United States. This shell is also sometimes called Clench's Helmet.

Citations

MolluscaBase eds. (2021). MolluscaBase. Cassis madagascariensis Lamarck, 1822. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=419778 on 2021-06-23

Rosenberg, G., F. Moretzsohn, and E. F. Garc�a. 29. Gastropoda (Mollusca) of the Gulf of Mexico, Pp. 579�699 in Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico�Origins, Waters, and Biota. Biodiversity. Texas A&M University Press, College Station, Texas.

Morris, P. A. (1987). A field guide to shells: Atlantic and Gulf coasts and the West Indies (3rd ed.). Houghton Mifflin.