The composition and structure of a protected coral reef in Cam Ranh Bay in the South China Sea

A nonstructural reef at Hon Nai Island in Cam Ranh Bay (southern Vietnam) was investigated. In comparison with most of the coastal continental and island coral reefs of this region, it is characterized by high species richness of reef-building corals, among them scleractinians. A total of 34 species of Acropora were found, which represent 80% of the total species composition of this scleractinian genus on the reefs of Vietnam and 25% on the reefs of the Indo-Pacific. Among 169 species of scleractinians found on the reef of Hon Nai, Favia sp. nov. was previously unknown to science. The vertical bionomic zonality of the reef corresponds to a zonal distribution of environmental factors and is similar to that on reefs of the Gulf of Siam and various areas of the Pacific and the Caribbean Basin. The thriving of the Hon Nai island reef may be connected with protective measures undertaken by the Government of Vietnam and the minimization of anthropogenic impacts due to the activities of the Sanest Co.