Abstract
Deep-water Ascidia escabanae known previously only from Escabana Trough, NE Pacific and Ciona pomponiae, originally described from Galapagos Islands are recorded at abyssal and bathyal depths in the region of Commander Islands and East Kamchatka in NW Pacific. Ciona gefesti is a junior synonym of C. pomponiae. The northern Atlantic species C. gelatinosa Bonnevie, 1896 (previously thought to be a subspecies of C. intestinalis and related to the Pacific Ocean C. mollis) is redescribed here and shown to be a distinct species. Also discussed are several littoral and bathyal Molgula spp. considered previously as closely related or possibly conspecific that are shown here to be separate species readily distinguished by their gonads. Molgula beringense sp.n. is described from the vicinity of the Bering Island.References
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