Genus Diogenion Codreanu, Codreanu & Pike, 1960

Diagnosis: Female head with dorsal groove; antennulae broad, antennae reduced; small maxilliped present. Oostegites 1 7 present; oostegite 1 without ascendant lobe, with strongly developed recurrent lobe lined with pleatlike folds; brood pouch formed by overlapping of oostegites 1 4, oostegites 5 7 reduced. Pereopods 1 7 present. Pleon slender, heart tubercle in pleomere 1; pleural lamellae, pleopods and uropods absent. Male with both pairs of antennae present, antennulae projecting beyond margin of head; head not fused with pereomere 1. Pereopods 1 6 present, multisegmented; lacking pereopod 7 or greatly reduced. Pleon of five segments plus pleotelson, medioventral spines absent, uropods present. Epicaridium larva with pereopods 1 6 isomorphic; lacking pereopod 7; pereopod 6 similar in length to pereopod 5. Pleon with five pairs of biramous pleopods. Pleotelson tapering to point. Uropods with endopod slightly longer than exopod. Cryptoniscus larva unknown.