Mactra veneriformis; trough shell
A species of bivalve mollusk; the name is usually written in katakana as シオフキガイ.
The Mactra veneriformis is a type of shell commonly found during clam digging.
Kanji spelling exists but is rarely used; the word is usually written in kana.
The name シオフキガイ (潮吹貝) literally means 'tide-spouting shell', referring to the way the clam squirts water when disturbed. The exact historical derivation is uncertain.