Early Middle Miocene Radiolaria from Nicobar Islands Northeast Indian Ocean

In the tropical Northeast Indian Ocean, Neogene sediments of the Andaman an d Nicobar Islands belong to a deep water marine facies rich in Radiolaria. Within the Nicobar group of islands, moderately rich radiolarian assemblage s from Nancowry and Kamorta islands have been studied. One hundred-twenty s pecies belonging to the Dorcadospyris alata Zone (similar to 15-13 Ma) are herein reported and illustrated. This is the first detailed record of Early Middle Miocene radiolarian taxa from land-based sections of Andaman-Nicoba r Islands and it is hoped that it will provide a database for comparative s tudies between the tropical radiolarian faunas of the Pacific and Indian oc eans.