Caeca present and functional. Oil-gland nude. Palate schizognathous, the vomer truncated behind; basipterygoid processes present. Sternum with a broad shallow incision on each side behind. Semitendinosus muscle present. Aftershaft to feathers very small.
Nest none: the eggs, generally two in number, are laid on the ground and (doubtless because of the protection thereby afforded) differ from those of all other Macrochires by being coloured. The young are hatched helpless, but covered with down. All members of this suborder are crepuscular and nocturnal.
A single family.