The Flora of Somalia is edited by Mats Thulin and published by the Royal Botanic Gardens Kew. It cover alls vascular plants known to occur in Somalia. The Somali flora is very rich in comparison with other arid areas in Africa. Several hundred species are endemic and they constitute a unique genetic resource, and in many cases they are of great potential value for arid countries in general. Of particular interest are the relict occurences of many apparently ancient arid elements, often with their closest relatives  not in surrounding regions but rather in areas such as Namibia, Pakistan or even Mexico and southern U.S.A.