Comparative study of autecological, morphological, anatomical and karyological characteristics of Acanthophyllum ejtehadii Mahmoudi & Vaezi (Caryophyllaceae): a rare endemic in Iran

Abstract

Characterizing traits of a species in its habitat is substantial for planning a practical conservation program.<br><br>Acanthophyllum ejtehadii Mahmoudi & Vaezi (Caryophyllaceae) is a recently established endemic species for flora of Iran and has<br><br>a narrow non-conserved natural habitat in Radkan region of Chenaran, Razavi Khorasan Province. The soil and climate of Radkan<br><br>was studied and the ecological, morphological, anatomical, and karyological aspects of A. ejtehadii were investigated to obtain a<br><br>comprehensive knowledge about this species and its natural growth conditions. Field observations were performed during the<br><br>growing seasons in 2014 2015 and 29 vegetation samples were collected as data. Results showed that this plant grows in<br><br>mound-like sites on clay-loam soils at mean elevation 1279 m.a.s.l. in arid climate. Acanthophyllum ejtehadii is a thorn-cushion<br><br>form chamaephyte plant. This Plant grow gradually in early-January, the flower unfolds in early-June and the matured seeds are<br><br>produced in mid-July. A. ejtehadii is a diploid (2n=2x =30) species and has homogenous karyotype. Having unique morphological<br><br>and anatomical adaptations such as expanded surface roots, reduced leaf area and thickened cuticle, this plant grows successfully in<br><br>harsh environments. These mechanisms are specific to this specific kind of Acanthophyllum species. The Speciation time of this<br><br>plant was estimated not more than 200 thousand years ago and if Radkan is preserved from anthropogenic disturbance, this species<br><br>could expand its distribution area.