Hysteroconcha dione
Hysteroconcha dione or the elegant Venus clam, formerly known as Venus dione, is a species of bivalve mollusc in the family Veneridae, the Venus clams.
The shell is whitish pink, with a row of long curved spines on each valve.
The species was named in Systema Naturae in 1758 by the Swedish naturalist Linnaeus. Both there and in his 1771 Fundamenta Testaceologiae, he described the shell in "disquieting" sexual terms.
Etymology
The species was named in 1758 by the Swedish naturalist Linnaeus as Venus dione, Venus being the name of the Roman goddess of love, and especially of sex.The specific epithet Dione is the name of the mother of Venus in Roman mythology. The later generic name Hysteroconcha is from Greek hyster, womb, and Latin concha, shell.
Description
The shells of Hysteroconcha dione can reach a length of about. The color of the whole shell is very pale or whitish pink, with whitish interior. The anterior end is broadly rounded, while the posterior is lightly sloping. The surface of each valve is characterized by several sharpened concentric and prominent ribs. This rare species is unusual in that it has a double series of long, curved spines on the posterior slope of each valve.A closely related species from the Eastern Pacific is Pitar lupanaria.