- A minute tube-dwelling colonial acorn worm found chiefly in deep water.
More example sentences
- Class Pterobranchia, phylum Hemichordata
- The SSU data supported enteropneust paraphyly by placing acorn worms of the family Ptychoderidae as the sister to a group consisting of pterobranchs + acorn worms of the family Harrimaniidae.
- Previously, hemichordates were thought to be paraphyletic, with enteropneusts (acorn worms) more closely related to chordates and pterobranchs closer to echinoderms.
- The ciliary bands on the phoronid and brachiopod tentacles are upstream-collecting bands with separate cilia on monociliate cells just like those of larvae or adults of pterobranchs, echinoderms and enteropneusts.
More definitions of pterobranchDefinition of pterobranch in:
- The British & World English dictionary