Distribution and diversity of recurrent groups of demersal fishes in the South China Sea off Viet Nam

The distribution and diversity of demersal fish communities were described in the South China Sea off Viet Nam from December 1968 to July 1969. The first recurrent group including lizardfish as a principal member was located dispersedly along coastal front from winter to summer. Snapper which was a principal member of the second recurrent group coexisted with largeeyed bream at 40-60m depth in winter. However, snapper coexisted with grunt in the shallow region less than 40m depth in summer. Diversity was relatively high in southeastern area, and was low off the Mekong delta.