Abstract
A male monstrilloid copepod of the genus Cymbasoma Thompson, 1888, collected in 1908 by the U.S. Fisheries Steamer "Albatross" off Mindanao, Philippines, and deposited in the U.S. National Museum of Natural History, was originally identified and labeled as Monstrilla leucopsis (sic) Sars, 1921 by C. B. Wilson. Reexamination of this historical sample revealed that the specimen is in fact assignable to Cymbasoma bullatum (A. Scott, 1909), described from specimens collected in 1899 in the Moluccan Sea during the Dutch "Siboga" Expedition. My earlier redescription of this species, based on the incomplete, damaged specimens of the type lot, lacked taxonomically relevant details and is supplemented herein. This species can be distinguished from its congeners by a combination of characters including the body proportions, armature of the antennules, presence of an anterior rostral protuberance, and structure of the genital lappets. New characters for distinguishing males of Cymbasoma species are evaluated. A relatively recent (1981) record of C. bullatum in Japan was evaluated in the light of these new data. Several differences in, e.g., antennulary armature, proportions of fifth pedigerous and anal somites, and morphology of the genital lappets, suggest that the Japanese specimens represent an undescribed taxon.References
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