Abstract
The green species Caulerpa taxifolia (Caulerpaceae), native e to the West Australia, is reported for the first time from pelagic zone in Marine research center located in Tajura belong to Tripoli province - Libya. All specimens, which are small and easily overlooked, were found in coast rock habitats in the pelagic zone, at depths in the range of 1 - 4 m, growing freely or attacked to the rocks by rhizoids. Morphological features are described and discussed.