The members of the genus live in tubes at the bottom of the sea.

Like other phoronids, members of this genus are benthic filter feeders with a worm-like body encased in a loosely fitting chitinous tube.

The genus is characterised by the epidermis folding under itself at the collar beneath the lophophore (feeding organ).

The gut is U-shaped, with the anus close to the mouth.

A 2018 phylogenetic analysis indicates that Phoronopsis is a monophyletic genus, while Phoronis is paraphyletic.