九州における熱帯産ヒルガオ科植物の海流散布

抄録

Distribution expansion of several tropical Convolvulaceae species by ocean current dispersal were observed on the coast of Kyushu, Japan. Except Ipomoea pes-caprae which have been often reported, seedlings or adult plants of eight species from sea-borne seeds were newly found on or near the drift zone of many beaches; I. alba, I. cairica, I. fimbriosepala, I. stolonifera, Merremia peltata, Operculina turpethum and Stictocardia tiliifolia. These localities are beyond each producing area where species produce seeds and complete the life cycle.　These plants from sea-borne seeds were found on beaches where I. pes-caprae and tropical drift fruits and seeds were also found. Distribution expansion of these tropical Convolvulaceae species is a good indicator of global warming.