Geographical Distribution of the Brown Alga Tinocladia crassa (Suringar) Kylin in Ryukyu Islands

Abstract

Distribution of the edible brown alga Tinocladia crassa in the Ryukyus was first described by Okamura in 1907. Some authors also reported that the habitat of this species is distributed from Okinawa to Fukushima Prefecture probably based on Okamura's findings. Later, some other authors showed that this species is distributed in Amami-ohshima Island and Mage Island. Surveys on the culture and ecology of two Chordariaceae species conducted during the period from 1972 to 1992 showed that habitat of this species is not expanded from Iheya and Okinawa Islands to Iriomote Island. Further studies by the present author on the distribution of this species showed that T. crassa does not exist in the Okinawa and Sakishima groups of Ryukyu Islands. Thus, it seems that the distribution of T. crassa on the southern part of Japan is limited to Amamiohshima Island.