PHYLOGENY OF THE GENUS EREMURUS (ASPHODELACEAE) BASED ON MORPHOLOGICAL CHARACTERS IN THE FLORA IRANICA AREA

A phylogenetic analysis of Eremurus (Asphodelaceae) based on morphological data is presented. A total of twenty-five characters including 20 gross morphological, 4 palynological and 1 chromosomal characters were analyzed to reconstruct phylogenetic relationships for 24 taxa of Eremurus and Trachyandra malosana plus Asphodelus tenuifolius and two Asphodeline species as outgroups. Maximum parsimony approach as implemented in PAUP* using heuristic search and branch swapping option of tree bisection-reconnection were used for phylogenetic analyses. The analysis of characters with successive weighting using rescaled consistency index generated more resolved and supported trees than the analysis with equally weighting characters. The analyses showed that T. malosana is well allied with a clade of Eremurus species. Among Eremurus species analyzed, E. persicus and a subclade of E. kopetdaghensis and E. luteus comprise the basal most branches as sisters to the remainder. Eremurus subgenus Henningia with 15 taxa was paraphyletic; whereas, nine members of Eremurus subgenus Eremurus formed a well supported monophyletic group for which E. furseorum of the former subgenus was sister taxon. Sections Henningia (of subgenus Henningia) and Eremurus (of subgenus Eremurus) are also appeared to be non-monophyletic while the section Ammolirion (of subgenus Eremurus) is monophyletic. Medium size pollen grain, (25-50 µm) and chromosome number of 2n=14 are shared by Eremurus and Trachyandra. Three characters including non-branched inflorescence, basifixed stamens and ellipsoidal pollen grains are synapomorphies for the genus Eremurus solely. Tubular/campanulate flowers, incurved tepals and tepals with 3-5 nerves are synapomorphies for the subgenus Eremurus. Similarly exerted stamen is a synapomorphy for the subgenus Eremurus and E. forseorum (from subgenus Henningia). The tubular flowers (rather than campanulate) and the thinnest pollen exine are putative synapomorphies for the section Ammolirion. The remaining characters were evolved homoplasiously or ambiguously among these taxa.