The Integrated Marine and Coastal Regionalisation of Australia (IMCRA), formerly the Interim Marine and Coastal Regionalisation for Australia, is a biogeographic regionalisation of the oceanic waters of Australia's exclusive economic zone (EEZ). As of 2008, the most recent version is IMCRA Version 4.0. IMCRA actually defines two bioregionalisations: a benthic bioregionalisation, based on biogeography of fish together with geophysical data; and a pelagic bioregionalisation, base on oceanographic characteristics. The benthic bioregionalisation incorporates three separate regionalisations: