Improvements in the phylogeny of Epilobium and Chamaenerion inferred from nrDNA and cpDNA data focusing on Türkiye

: Epilobium and Chamaenerion included 165 and 8 species over the world, respectively. The members of the genera are distributed particularly in moist habitats from subpolar to tropical regions. This paper aims to provide improvements in the phylogeny of the genera Epilobium and Chamaenerion using Internal Transcribed Spacer (ITS) of nuclear DNA and mat K gene sequence data evaluation with maximum parsimony, maximum likelihood, and Bayesian inference criterations. A total of 188 individual accessions belonging to 28 taxa were newly generated and 110 sequences imported from GenBank (NCBI) were analysed. The nrDNA and plastid DNA gene trees supported to treat Epilobium and Chamaenerion as separate genera in two well-supported clades. The mat K analyses revealed a better resolution than nrDNA ITS within the Chamaenerion clade and supported the inclusion of C. angustifolium in the sect. Chamaenerion . However, most of the examined species mostly fell into the polytomy in both trees excluding E. roseum subsp. consimile which should be considered a distinct species in the Epilobium contrary to morphological treatment in many national flora books. Both phylogenetic trees also support distinguishing E. prionophyllum from E. anatolicum previously treated as a subspecies of E. anatolicum . In conclusion, these preliminary phylogenetic analyses have contributed significantly to the determination of the limits of members belonging to Epilobium and Chamaenerion distributed in Türkiye.