Type species: Polynoe (Macellicephala) mirabilis McIntosh, 1885, by monotypy. Gender: feminine. = Macellicephala mirabilis McIntosh, 1885.
Diagnosis. Body with 18 segments. Elytra and elytrophores 9 pairs, on segments 2, 4, 5, 7, 9, 11, 13, 15 and 17. Prostomium bilobed, with or without paired frontal filaments; with median antenna and smooth palps. Pharynx with 9 pairs of papillae and 2 pairs of jaws, with smooth margins. Segment 1 [(= tentacular segment, as used by Pettibone (1976)]) without chaetae. Segment 2 with buccal (ventral) cirri longer than following ventral cirri, attached to basal parts of parapodia lateral to mouth. Parapodia biramous, with shorter notopodia and long neuropodia, both rami with elongate acicular processes. Nephridial papillae present from fifth segment, usually largest on segments 10, 11 and 12. Pygidium medial to greatly reduced parapodia of segment 18.