Labiatae of South-West Asia: diversity, distribution and endemism

Abstract

SynopsisThe Labiatae of SW Asia arc analysed. There is a major development of the family in this area with c. 1100 species, much morphological diversity, many illuminating distribution patterns and very high endemism levels; species endemism averages over 70% in the medium-sized and large genera. Areas of high concentrations of endemic taxa are indicated. The very significant differences between the Labiate floras of Turkey, Iran and Afghanistan throw doubt on designating all the steppic part of the area as Irano-Turanian; there is a strong Mediterranean floristic connection throughout much of Turkey and little evidence of Irano-Turanian influence. There are numerous taxonomically very isolated genera and species; some of these genera have very restricted distributions, a few are almost cosmopolitan.

Phylogenetic relationships among species of the subsection Dendrophlomis Bentham

“…Both sections are spread from the Mediterranean region to central Asia and China; but while species of the section Phlomoides occur mostly in central Asia and China, species of the section Phlomis appear mainly in the Mediterranean region. Turkey and Iran were indicated as the main centers of diversification in the Mediterranean region for the section Phlomis (Hedge, 1986). In particular, southern and eastern parts of the former and north-western part of the latter were proposed as centers of origin of that section.…”

“…In particular, southern and eastern parts of the former and north-western part of the latter were proposed as centers of origin of that section. Nevertheless, Turkey has twice the number of species (34) and also nearly twice a higher endemism rate (57%) of species belonging to section Phlomis compared to Iran, where the numbers are 18% and 33% respectively (Hedge, 1986).Measurement of genetic variation within and between plant species is important for several reasons including delimitation of species, conservation of endangered species and construction of phylogenetic relationships among species. Several kinds of methods were used to measure levels and patterns of genetic variation, which range from Yüzbaşıoğlu, E. and Dadandı, M.Y.…”

“…In particular, southern and eastern parts of the former and north-western part of the latter were proposed as centers of origin of that section. Nevertheless, Turkey has twice the number of species (34) and also nearly twice a higher endemism rate (57%) of species belonging to section Phlomis compared to Iran, where the numbers are 18% and 33% respectively (Hedge, 1986).…”

“…Due to advantages associated with RAPD, it has been widely used in plants to investigate genetic relationships among species and genetic diversity within species (Esselman et al 2000;Rout et al 2003;Castiglioni and De Campos, 2005;Choudhury et al 2006;Fernandez et al 2006;Sheng et al 2006;Yuzbasioglu et al 2006). Some studies have been conducted to elucidate relationships among some Phlomis species by using morphological, anatomical, palynological and cytological traits (Huber-Morath, 1982;Hedge, 1986;Taylor, 1998). In Phlomis, based on these studies, two main sections have been recognized: Phlomis and Phlomoides, with the former section being subdivided into three subsections, Gymnophlomis, Dendrophlomis and Oxyphlomis.…”

Estimation of phylogenetic relationships of Phlomis species based on seed protein polymorphism

“…Species of section Phlomis, which have corolla with curved upper lip and trifid lower lip with large median and smaller lateral lobes, differs from species of section Phlomoides that have corolla with straight upper lip and trifid lower lip with sub equal lobes (Azizian and Moore, 1982). Section Phlomis occurs mostly in the Mediterranean region, where Turkey is regarded as one of the primary center of diversification for species of the section (Hedge, 1986). For instance, in the Flora of Turkey, the genus Phlomis consists of 34 species and six varieties, of which 22 are endemic to that flora (Huber-Morath, 1982).…”