一、前言水螅水母类Hydromedusa管水母类Siphonophorae为浮游动物组成的重要类群.虽然它们含水量高,经济意义小,常排于饵料生物之外,而且它们中的大多数会捕食浮游甲壳动物及某些经济鱼类的幼体,是渔业及养殖业中的敌害,但是它们种类多,数量大,分布广,某些种类可作为一定海流或水团的良好指标.因此,开展对其深入地调查研究,在经济上和理论上都有一定意义. I. INTRODUCTION Siphonophorae, a Hydromedusa jellyfish, is an important group of zooplankton, and although they have high water content and low economic value, they are often excluded from food organisms and most of them prey on plankton and some The larvae of these economic fishes are predators in fisheries and aquaculture, but they are numerous, large in number and widely distributed, and some species may be good indicators of certain ocean currents or water masses. Therefore, Research, both economically and theoretically, has some meaning.