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Midshipman fish belong to the genus ''Porichthys'' of toadfishes. They are distinguished by having photophores (which they use to attract prey and after which they are named, reminding some of a naval uniform's buttons) and four lateral lines. Typical midshipman fishes, such as the plainfin midshipman (''Porichthys notatus''), are nocturnal and bury themselves in sand or mud in the intertidal zone during the day. At night they float just above the seabed. Some species have venomous dorsal spines and are capable of inflicting serious injuries if handled. There are three genders of midshipman fish: females, type I males, and type II males. Type I and type II males have different reproductive strategies, and can be distinguished from each other based on physical characteristics. Type I males are eight times larger in body mass, and have much larger vocal organs. Type II males’ reproductive organs are seven times the size of type I males.〔Brantley RK and Bass AH. 1994. Alternative male spawning tactics and acoustic signaling in the plainfin midshipman fish, ''Porichthys notatus''. ''Ethology'' 96: 213-232.〕 Female and type II male midshipman fish can be distinguished from each other by the female’s slightly larger size, and the type II male midshipman’s large reproductive organs.〔Lee SFL and Bass AH. 2006. Dimorphic male midshipman fish: reduced sexual selection or sexual selection for reduced characters? ''Behavioral Ecology'' 17(4): 670-675.〕 ==Species== There are currently 14 recognized species in this genus: * ''Porichthys analis'' C. L. Hubbs & L. P. Schultz, 1939 (Darkedge midshipman) * ''Porichthys bathoiketes'' C. R. Gilbert, 1968 * ''Porichthys ephippiatus'' H. J. Walker & Rosenblatt, 1988 (Saddle midshipman) * ''Porichthys greenei'' C. H. Gilbert & Starks, 1904 (Greene's midshipman) * ''Porichthys kymosemeum'' C. R. Gilbert, 1968 * ''Porichthys margaritatus'' (J. Richardson, 1844) (Daisy midshipman) * ''Porichthys mimeticus'' H. J. Walker & Rosenblatt, 1988 (Mimetic midshipman) * ''Porichthys myriaster'' C. L. Hubbs & L. P. Schultz, 1939 (Specklefin midshipman) * ''Porichthys notatus'' Girard, 1854 (Plainfin midshipman) * ''Porichthys oculellus'' H. J. Walker & Rosenblatt, 1988 (Smalleye midshipman) * ''Porichthys oculofrenum'' C. R. Gilbert, 1968 * ''Porichthys pauciradiatus'' D. K. Caldwell & M. C. Caldwell, 1963 * ''Porichthys plectrodon'' D. S. Jordan & C. H. Gilbert, 1882 (Atlantic midshipman) * ''Porichthys porosissimus'' (G. Cuvier, 1829) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「midshipman fish」の詳細全文を読む スポンサード リンク
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