Ryukyu islands

The relatively late start-up growth of modern coral reefs in the Ryukyu Islands may be due to the main flow of the Kuroshio Current inferred to reentering into the East China Sea around 8600 BP (¹⁴C, Diekmann et al., 2008) along with the high-latitudinal locality of the archipelago. The development of modern reefs shows the distinct latitudinal gradients in size and distribution until around 30°N. The reef founded in the Iki Island at 33°48’N is a favid reef (Yamano et al., 2001) partially distributing in the area. It is different from the series of acroporid reefs in the Ryukyu Islands and there is a gap of reef development between 30°Nand 33°48’N. The gradually disappearing of modern reefs at high latitude along Ryukyu Islands is unique in the global coral reef distribution.