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Filogenija in biogeografija skupine Euphorbia barrelieri 
(Euphorbiaceae)
Phylogeny of Euphorbia barrelieri group (Euphorbiaceae)
Bo ž o Fr a j M a n
1
 & P e t e r Sc h ö N S W e t t e r
2
1
  Oddelek za biologijo, Biotehniška fakulteta, Univerza v Ljubljani, Večna pot 111, SI-
1000 Ljubljana; bozo.frajman@bf.uni-lj.si.
2
  Oddelek za biogeografijo, Univerza na Dunaju, Rennweg 14, A-1030 Dunaj, Avstrija.
Euphorbia is one of the largest genera of seed plants with mostly tropical distribution. 
Around 100 species are native to Europe (Euphorbia subg. Esula) with the highest diversity 
in Southern Europe. The E. barrelieri group consists of c. five species distributed in the 
Eastern Alps, Balkan and Apennine Peninsulas. Euphorbia saxatilis is endemic to the 
northeastern Calcareous Alps of Austria, E. triflora is disjunctly distributed on Čaven in 
Slovenia and on Velebit and Gorski Kotar in Croatia, E. kerneri on the southern outskirts 
of the Carnic Alps and the southwestern outskirts of the Julian Alps, and E. hercegovina in 
the Dinaric Mountains from Bosnia and Herzegovina to Montenegro as well as on Pelješac 
Peninsula in Croatia. Euphorbia barrelieri is more widespread, E. barrelieri subsp. 
barrelieri is confined to the Apennine Peninsula and E. barrelieri subsp. thessala to the 
southern Balkan Peninsula.
The aim of the study was to test hypotheses on the relationships among the taxa 
based on classical morphological and biogeographical assumptions, as well as to infer the 
phylogenetic position of the group within Euphorbia, using AFLP and chloroplast (trnT-
trnF) as well as nuclear ribosomal DNA sequences (ITS), respectively.
The sequence data suggest that the E. barrelieri group as traditionally circumscribed 
is not monophyletic, E. nicaeensis (incl. E. glareosa) and E. segueriana (incl. E. niciciana) 
are nested within it. The sister to the group is E. pithyusa from the western Mediterranean. 
Chloroplast and nuclear phylogenies are incongruent, suggesting a complicated evolutionary 
history. The ITS phylogeny is in several respects congruent with patterns suggested by 
AFLP data. Euphorbia kerneri and E. triflora form distinct clades and should be treated as 
independent species. Euphorbia herzegovina subsp. javoriensis is clearly nested within E. 
triflora. Additional studies to better understand the evolutionary history of the group and 
relationships among the taxa are underway. 
Bo ž o Fr a j M a n & p e T e r Sc h ö n S w e T T e r : Filogenija in biogeografija skupine …