Macridiscus aequilatera
NameMacridiscus aequilatera
Scientific NameMacridiscus aequilatera
Common NameAequilateral Venus Clam, Aequilateral Hard Clam
FamilyVeneridae
GenusMacridiscus
Speciesaequilatera
Geographic DistributionIndo-Pacific, particularly common in East Asia (e.g., Japan, Korea, China).
Habitatintertidal
Average Size (mm)Typically ranges from 40 to 70 mm in length.
Identifying FeaturesProminent concentric growth lines on the shell surface. Highly variable but often distinctive color patterns, including radial rays, zigzag markings, or concentric bands. Ovate to subtrigonal shape with a relatively smooth exterior apart from growth lines.
Raritycommon
Author Citation(Sowerby II, 1853)
Description
Three specimens of Macridiscus aequilatera, commonly known as the Aequilateral Venus Clam, are displayed on black sand. The shells exhibit notable color polymorphism: one is predominantly white with striking black or dark grey chevron-like patterns, another is a uniform dark grey/black with subtle concentric lines, and the third is light brown/tan with darker, somewhat mottled concentric bands. All shells show distinct concentric growth lines. They are bivalves, characterized by their ovate to subtrigonal shape.
