Marphysa sanguinea (a species of eunicid worm)
A marine polychaete worm, sometimes called 'rock worm' or 'blood worm' in English. Used in fishing bait and occasionally in cuisine.
Many people use Marphysa sanguinea as fishing bait.
Marphysa sanguinea lives among the rocks on the shore.
Katakana spelling is common for this organism name; usually written in kana.
Kanji spelling is rare and may not be widely recognized; the katakana form is preferred.
Compound of 岩 (iwa, 'rock') and 虫 (mushi, 'worm'), referring to its habitat among rocks. The exact derivation is straightforward.