Iophon is a genus of sponges belonging to the family Acarnidae.

[2] This genus contains species with non-fistulose, massive, branching or encrusting growth forms.

The ectosomal (outer) skeleton is made of tylotes (long, slender megascleres with knobs at both ends) with microspined bases.

[3] The microscleres include bipocilla and palmate anisochelae with spurs.

They are modified anisochela in which the wing-like alae are joined together by a short curved shaft.