【Reading】ばかがい

【English Name】Aoyagi (Surf Clam)

A bivalve belonging to the family Mactridae, with the scientific name Mactra chinensis. Its main habitat is the sandy bottoms of inland bays along the coasts of East and Southeast Asia, and within Japan it is widely seen from Hokkaido to Kyushu. The shell length is about 8 cm, and a notable feature is that the thin shell is fragile to external force and easily broken.

In the world of sushi it is known by the name "aoyagi." It is said that this name took hold because Edo-period chefs avoided using the writing "bakagai" (foolish clam) on their menus and instead borrowed the place name of Aoyagi in Kazusa Province (present-day Ichihara City, Chiba Prefecture), then a major distribution hub, to rename it. Note that "aoyagi" is the name for the entire soft body once the shell is removed, and differs in meaning from being an alternative name for the clam itself.

Each part has its own distinct name. The adductor muscle is called "kobashira," and just the foot cut out is called "shitakiri." Kobashira is prized for kakiage tempura and gunkan rolls, while aoyagi and shitakiri are ingredients that shine in nigiri sushi and nuta dressing.

Several theories have been put forward about the origin of the name: that "hayagai" (easily broken clam) became corrupted from its fragile shell; that it comes from the way it opens its shell and extends its foot; that it comes from being landed in great quantities in bumper catches; and that it derives from the sound of Makuwari (the present-day Makuhari district), a production area. It burrows into the sand faster than the asari clam or hamaguri clam, and behavior of dodging predators by jumping with its foot has also been observed.