phoronid; horseshoe worm
A wormlike marine animal of the phylum Phoronida. Primarily a technical term in biology.
Phoronids live in tubes they construct in the sandy or muddy seafloor.
At low tide, phoronid tubes can sometimes be seen on this beach.
Usually written in katakana as a biological term; the kanji form 箒虫 is rare.
Kanji form is seldom used; the katakana spelling is standard in scientific contexts.
From 箒 (ほうき, 'broom') + 虫 (むし, 'worm, insect'), referring to the broom-like tentacles. The exact origin of the name is uncertain, but it is a calque of the scientific name Phoronida (from Greek phoronis, 'broom').