L. Agassiz, 1860
Body compressed in the tentacular plane, expanded on each side of mouth to form a pair of oral lobes. Subtentacular comb rows giving rise to four flap-like auricles, usually shorter than substomodeal comb row. Meridional canals much longer than comb rows, extending into oral lobes. Paragastric canals join subtentacular meridional canals orally. Statocyst usually deeply sunk. Tentacles migrate orally as lobes develop, tentacle sheaths are lost, and tentacles become reduced, surrounding mouth and extending to oral lobes.
Family Bolinopsidae
Genus Bolinopsis
Genus Mnemiopsis
Family Leucotheidae
Genus Leucothea
Family Eurhamphaeidae
Genus Eurhamphaea
Family Ocyropsidae
Genus Ocyropsis