Genus Theonella Gray, 1868

Rhachella Sollas, 1888

Diagnosis. with characteristics of Theonellidae; ectosomal spicules as phyllo- to dichotriaenes; large choanosomal oxeas sometimes present; megascleres sometimes completely absent; microscleres as small, acanthose microrhabds only, sometimes curved slightly.

Type-species. Theonella swinhoei Gray, 1868; by monotypy (Gray 1868).