Aquaculture related invasion of the exotic <Emphasis Type="Italic">Artemia franciscana</Emphasis> and displacement of the autochthonous <Emphasis Type="Italic">Artemia</Emphasis> populations from the hypersaline habitats of India

Autochthonous parthenogentic Artemia populations have been reported from Indian hypersaline habitats since 1950s. Exotic Artemia franciscana was imported and introduced into India as live food for aquaculture since the early eighties. To assess the present status of the Artemia populations and the possibility of invasion by the introduced A. franciscana in Indian Salinas, an extensive study was conducted using conventional and molecular approaches. Morphological and biometric observations, crossbreeding experiments and molecular and phylogenetic analysis using Internally Transcribed Spacer-1 sequence revealed the extensive presence of alien, sexual A. franciscana populations in various hypersaline areas. Individual culture experiments and crossbreeding studies further confirmed the absence of autochthonous parthenogentic Artemia populations. Lack of regional endemism in populations of distant origins was evident, indicating that the invaded populations have naturalized and are in the process of evolution. This forms the first report of invasion by A. franciscana in hypersaline habitats of Indian subcontinent and further studies are required to assess the biological implications of this invasion.