Can wings can be present on a snail snail? The answer is, of course not! But, this post concerns the so-called “winged triton” seashell, more formerly known a Gyrineum perca. In scientific description, these so-called “wings” are more properly referred to as varices. They are aligned along the sides of the shell, and they probably provide stability on the ocean floor for the shell. The growth of varices on shells is referred to as “episodic,” growth; that is to say, it is intermittent but fast. Initially, a thin-flexible expansion of the shell is built, and as this material is secreted, it is mineralized and gradually thickened, over a period of several days. The gastropod otherwise remains inactive and concealed until the new shell material is hardened (Vermeij, 1993).
For you “old timers,” this particular seashell was colloquially known as the “winged triton” or “maple-leaf triton.” For awhile, it was previously referred to in the scientific literature as Apollon perca or Biplex perca, but if you regularly read my posts, you will be fully aware that the names of sea-shells are commonly in a state of flux these days; mainly, because of new DNA data about these animals.
Gyrineum (Biplex) perca, length 55 mm, width 45 mm, thickness 16 mm.apertural view. A) apertural view. B) abapertural (back) view. C. Right-side view. No Locality data available.
Another specimen of Gyrineum perca: length 52 mm, width 40 mm, thickness 15 mm. This second specimen has an operculum [used to close off the aperture from predators]; the operculum consists of horny [=organic material which is not calcified]. Locality data not known.
According to WoRMS [World Register of Marine Species], the current classification of this seashell is:
Class Gastropoda
Order Littorinimorpha
Family Cymatiidae
Genus Gyrineum
Subgenus Biplex
Species perca (Perry, 1811)
The shell of Gyrineum (Biplex) perca ranges from 31 to 100 mm (1.2 to 3.9 inches) in length. The shell, which is white, yellowish, or pale brown, is quite flattened, with a large flange (“so-called wings”) along its two sides.
The modern-day distribution of Gyrineum (Biplex) perca is eastern Africa to Japan. It is essentially confined to warm (tropical) waters (Wikipedia, 2024).
Gyrineum is one of the 24 known genera of family Cymatidae Link, 1807. To view some of the species of Gyrineum that resemble Gyrineum perca (there are at least four other such species)—the differences being in the shape of the wings (flanges); for more information, see the following website: https://www.jaxshells.org/gryrineum.htm
References Cited:
Beu, A.G. 1998. Family Ranellidae. In Mollusca The Southern Synthesis, Part B. Fauna of Australia Volume 5. Pp. 799-802. CSIRO Publishing, Melbourne, Australia
Vermeij, G.J. 1993. A natural history of shells. Princeton Science Library. 207 pp.
Wikipedia. 2004.
WoRMS. 2024. World Register of Marine Species [https://marinespecies.org]
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