Recent attention to members of the sepiolid squid genusEuprymnaand symbiotic associations with luminescent bacteria (Vibrio fischeristrains) has prompted a review of this poorly-resolved group of squids. Twelve nominal species have been placed in this genus of which the majority are ill-defined, known only from their original descriptions and separated on the basis of inadequate characters. As a first step in resolving this group, a temperate Australian species, the Southern dumpling squid,Euprymna tasmanica, is here redescribed in detail. As the genusEuprymnacurrently stands, most members are only distinguished on the number and position of enlarged suckers in mature males. No diagnostic characters are available to identify females. All nominal species placed in this genus are reviewed and a key to proposed valid species is presented. Six species are considered here to be valid:Euprymna berryi, E. hoylei, E. morsei, E. scolopes, E. tasmanicaand an undescribed species treated here asEuprymnasp. 1.Euprymna similisis a synonym ofE. morseiof Japan. Due to inadequate original descriptions, and lost or poor type material, two species are considered here to benomen dubia(E. schneehageniandE. pusilla), while the taxonomic status of four additional species remain unresolved (E. albatrossae, E. bursa, E. phenaxandE. stenodactyla).