Phoronids (scientific name
Phoronida, sometimes called
horseshoe worms) are a
phylum of marine animals that
filter-feed with a
lophophore (a "crown" of tentacles), and build upright tubes of
chitin to support and protect their soft bodies. They live in most of the oceans and seas including the Arctic Ocean but excluding the
Antarctic Ocean, and between the
intertidal zone and about 400 meters down. Most adult phoronids are 2 cm long and about 1.5 mm wide, although the largest are 50 cm long.