China is one of 17 megadiverse countries, lying in two of the world's major biogeographic realms: the Palearctic and the Indomalayan. By one measure, China has over 34,687 species of animals and vascular plants, making it the third-most biodiverse country in the world, after Brazil and Colombia. The country signed the Rio de Janeiro Convention on Biological Diversity on 11 June 1992, and became a party to the convention on 5 January 1993. It later produced a National Biodiversity Strategy and Action Plan, with one revision that was received by the convention on 21 September 2010.