Eight species and four subspecies of the genus Echinosigra were identified in the samples collected during expeditions of the Institute of Oceanology in 1953-1989. They are E. vityazi n. sp. from the Indo-Pacific; E. phiale partita n. subsp. from the Subantarctic; E. fabrefacta, E. valvaedentata and E. antarctica which were previously considered as E. amphora subspecies. The samples were collected at 49 stations at the depths of 1026-7170 m. The genus is divided into two subgenera: Echinosigra with two genital pores, long neck and Echinogutta n. subgen. with four genital pores, short neck. E. vityazi n. sp. has the most lengthened test among echinoids; length is eight times as much as width. A key to identify all Echinosigra species and subspecies is given.
