中国的淡水水母

<正> 淡水水母为W.Sowerby于1880年6月9日于英国伦敦Regent公园一人工水池中首次发现,标本经E.R.Lankester研究,订名为Craspedacusta sowerbyi,于同年发表。自此以后才在世界各国陆续发现,主要是在欧洲、亚洲及美洲等温带地区,大洋洲也有发现。1907年日本人川井正方在我国湖北宜昌附近长江沿岸采得淡水水母标本,为日本学者丘浅次郎研究,当时误订为一新种Limnocodium kawaii,于1922年改为一变种L.sowerbyi

FRESHWATER MEDUSAE IN CHINA

The freshwater medusae were rare organisms.They were called Tao-huayu(peach blossom fish)in ancient times of china.Three handred years ago,morphology and ecology of them were recorded in many ancient Chiense books(Zhang,S.R.1609;Chen,M.L.1726;Wu,Y.C.1826).In 1609 Tao-hua-yu was recorded in“The Record of Gui County(vol.1).”Se-veral specimens were collected in the Yangtse River,Yichang in 1907 by Oka'A.and was identified to be a new varify Craspedacusta sowerbyi var.kawaii(Oka,1907,1922).Thirty years,later the freshwater medusa wasdiscovered from a rapidly increasing number of localities,mainly in the Ya-ngtse River valley and southeastern areas along the sea(He,Z.W.1964,1981)Since OKa's paper(1907)on the freshwater medusa(Limnocodium kawaii=Craspedacusta sowerbyi var.kawaii)from Yichang,there have been describedmore species in China.In 1939 Gaw and Kung reported Craspedacusta sinen-sis and C.sowerbyi var.kiatingi from Leshan(Kiating)and afterwards He(1980)described Craspedacusta sowerbyi hangzhouensis from west Lake andC.sowerbyi xinxiangensis from Xinyang.Recently He and Xu(1984),Heand Kou(1984)reported two new species C.ziguiensis from Zigui and C.sichuanensis from Sichuan。From specimens collected in many localities of China and the reportsobtained by us,We know that the freshwater medusae are widely distributedin China as following:Suzhou(Tomita,1942),Tai Lake(Lovegren,1930),West Lake(Fujiwara,1932;Tomita,1942;He,1980),Pudong Zhejiang, (Xue,1954),guangzhou(Liang,1936;H.T.Chen,1940),Hong Kong(Herklot,1940),Longnan,Jiangxi(Kimura,1937),Lingling,Hunan(Kimura,1937),Dongting Lake(Uchida and Kimura,1933),Xiamen(Tang,Yang,Fang,1936),Yichang(Oka,1907),Zigui(Kimura,1937;Heand Xn,1984),Badong.Yunyang,Changle(Kimura,1937),Taiwan(Shiehand Wang,1959),Xinyang(He,1980),Zunyi(Li and Sun,1984),Leshan(Lovegren,1930;Gaw and Kung,1939;Kramp,1950),Chongping(Kimura,1937;He,1983),Xinjin(Uchida and Kimura,1937),Zhong county(Kimura,1937),Chang shou(Cheng,1956),and Guan County(He and Kou,1984).And also discovered in Chengdu,Nanxi,Yiben,Mianyang,Tongliang,Nanxi,Hechuan,Fuling,Nanchong,Zhong(county,Changsha,Wuhan,Lizhuang(Sichuan),Yuanpu and Zhuantang(Zhejiang).Key to the Genus and Species of Freshwater Medusae1.gonads on stomach wall Genus Limocnida,2gonads on radial canals Genus Craspedacusta,32.Diameter of umbrella large;with tentaclesof different sizes L.tanganyicaeDiameter of umbrella small;with two distinctsereis of marginal tentacles L.indica3.Perradial tentacles not longer than others 4Perradial tentacles longer than others 54.Statocyst tubular;nematocyst wart elongated cylindrical or club-shaped;gonads pocket like,brownish yellow Craspedacusta sinensisstatocyst spherical;nematocyst wart ring-shaped;gon ads pocket-like,twisted,slightlygreenish C.sichuanensis5.Statocyst spherical;nematocyst not collectedinto cluster C.iseanumStatocyst tubular;nematocyst Collectedinto warts 66.Nematocyst warts spherical;arranged in a horseshoe C.ziguiensisNematocyst warts papilla-shaped;arranged in ring C.sowerbyi,77.Gonads bana-shaped,pink;nematocyst wartsconical,arranged irregular C.sowerbyi hangzhouensisGonads not band-shaped,greenish 88.Gonads triangular;nematocyst warts conicaland club-shaped,arranged annular C.sowerbyi xinxiangensisGonads not triangular 99.Gonads leaf-shaped;nematocyst warts papillashaped, arranged irragular C.sowerbyi var.kaw aiiGonads pocket-like;nematocyst warts hemisphericalarr anged in ring C.sowerbyi var。kiatingi