Centaurea in South-West Asia: patterns of distribution and diversity

Abstract

SynopsisIn SW Asia 260 species of Centaurea in 38 sections are recognised. Species numbers are highest in S and E Turkey and adjacent Iran and Iraq. East Iran and Afghanistan are poor in species. The number of sections is largest in NE Turkey (and adjacent Transcaucasia). Two hundred and one species are restricted to the area under study; the greatest number of narrow endemics is found in S and E Turkey. The subgenera and sections show quite different patterns of distribution and centres of diversity. The data presented point to E Anatolia and adjacent areas as the foremost centre of evolution for the genus and make probable a relatively recent speciation; an important secondary centre is S Turkey (and of course several other Mediterranean countries too). Some notes are added on the morphological variation in the genus and possible factors influencing its evolution.