noun
Barnea dilatata; a species of piddock
A type of boring clam found in marine environments. The name is usually written in katakana as ウミタケ.
ウミタケは岩に穴を開けてすむ二枚貝です。
The umitake is a bivalve that lives by boring holes into rocks.
Compound of 海 (umi, 'sea') + 茸 (take, 'mushroom'), likely from the shape of the siphon resembling a mushroom. The exact derivation is uncertain.