“Coleoptera Mosaic” prototype, from Pheromone: The Insect Artwork of Chrisiopher MarleyThe first beetles (Coleoptera, meaning “sheath wing”) evolved before the dinosaurs, 265 million years ago. They have since diversified to live in all habitats except the sea and the polar regions. Over 350,000 species have been described; that constitutes 40% of all insect species and about 25% of all known life forms. However, new species are being discovered all the time and the full number of species is unknown. Habitat loss is the greatest threat to the beetle. To date 75 known species are listed on the IUCN (International Union for Conservation of Nature) Red List of threatened species. Of these 20 species are listed as endangered, 10 as critically endangered and 15 as already extinct.