A new species of Tamarix (Tamaricaceae) from Hormozgan Province, S Iran, supported by morphology and molecular phylogenetics

Abstract

The genus Tamarix (Tamaricaceae) is a lineage of shrubs and trees with leaves reduced to scales and numerous species adapted to moist and often saline soils in arid and semi-arid climatesExtensive morphological variation and hybridization complicate species delimitation and identificationBased on both morphological and DNA sequence characters, Tamarix humboldtiana Akhani, Borsch & NSamadi is described as a new species from S IranPhylogenetic analysis of plastid rpl16 intron and trnG-trnS spacer sequences depicts a sister group relationship of its unique plastid haplotype to Ttetrandra, whereas nuclear ITS sequence data show close affinities to TkotschyiThe new species differs from Tkotschyi by distinctly pedicellate, 5-merous flowers and vaginate-amplexicaul leavesThe stem and foliar anatomy and the epidermal micromorphology provide additional characters differentiating the new species from TkotschyiThe gametic chromosome number of n = 12 reflects that of most of other species of the genusTamarix humboldtiana is a rare species living at freshwater riversides in S Iran and is according to current knowledge critically endangered.