Multiple origins of dendroid shrubs in the eastern M editerranean E uphorbia hierosolymitana group ( E uphorbiaceae) with description of a new species, E uphorbia lemesiana , from C yprus

The leafy spurges, E uphorbia subgenus E sula , have one of their diversity centres in the Mediterranean, which is considered to be one of the 25 biodiversity hot‐spots. The eastern M editerranean, in particular, is characterized by its high species richness and is therefore considered to be a cradle for lineage diversification. However, the area remains neglected in phylogenetic studies. Using nuclear ribosomal internal transcribed spacer ( ITS ) and plastid trn T ‐ trn F sequences, we explored the phylogenetic relationships in the predominantly eastern M editerranean E . hierosolymitana group, which is characterized by a woody habit. The widespread shrublets E . acanthothamnos , E . glabriflora and E . spinosa , which are similar in habit, are not most closely related, the last two forming a sister clade to other taxa. From the E . acanthothamnos alliance, dendroid shrubs evolved at least two, but possibly four, times, giving rise to widespread E . bivonae and E . hierosolymitana , the C retan endemic E . sultan‐hassei and the here newly described and genetically most divergent E. lemesiana , endemic to C yprus. We provide a taxonomic treatment and morphological comparison with the similar, but not most closely related, E . hierosolymitana . Our study underlines the phytogeographical peculiarity of C yprus and contributes to our current knowledge on the diversification patterns in the eastern Mediterranean. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society , 2015, 179 , 295–307.