Endemic species are organisms that live in a limited geographical area and nowhere else in the world. Differ by age relict endemic species (paleoendeme) and neoendeme. The relic endemics are species which in the past had a great range, but due to climatic and geographical changes and fierce competition in other species are much reduced. Cycas revoluta is endemic in eastern Asia and its natural distribution is from Japan to Java, Ginkgo biloba is endemic to eastern China, Metasequoia glyptostroboides endemic to Central China, Sequoia sempervirens is endemic to the coastal region of California and Oregon, Sequoiadendron giganteum is endemic to California (Sierra Nevada), Wollemia nobilis is endemic to Australia, and Zamia integrifolia endemic in the southeastern part of the United States, the Bahamas, the Cayman Islands, Cuba, Puerto Rico. The foregoing relict endemics originated from the Mesozoic. The next relict endemics originated from the Tertiary and they are endemics of Balkan peninsula. Picea omorica endemic to the east of Bosnia and western Serbia, Ramonda nathaliae and Ramonda serbica are endemic Serbia, Macedonia, Montenegro, Albania, Greece and Bulgaria. Some of these species can be found outside their natural range. Kept in arboretums and botanical gardens and many of them planted in parks as ornamental species. All described relict, exept R. nathaliae, running are on the IUCN Red List of Threatened Species.