Hemichordate genera

Balanoglossus is a genus of ocean-dwelling acorn worms. It has zoological importance because, being hemichordates, they are an "evolutionary link" between invertebrates and vertebrates. Balanoglossus specimens are deuterostomes, and resemble the chordates in that they possess branchial openings.

Planctosphaera pelagica is a hemichordate and the only known representative of the class Planctosphaeroidea.

Rhabdopleura is a genus of colonial sessile hemichordates belonging to the Pterobranchia class. They are exclusively marine, benthic organisms whose species occur within all major oceans and range in habitat from intertidal to . As one of the oldest living genera with a fossil record dating back to the Middle Cambrian, it is also considered to be the only living genus of graptolites.

Cephalodiscus is a genus of hemichordates in the family Cephalodiscidae of the order Cephalodiscida.

Harrimania is a genus of acorn worms belonging to the family Harrimaniidae.