Caucasian black grouse ( Tetrao mlokosiewiczi) is the endemic bird species in Caucasus hotspot and the distribution range includes Georgia, Russia, Azerbaijan, Armenia, Turkey and Iran. In Iran it only occurs at Arasbaran region in northwest of Iran and only 300 individuals inhabits a 100 square kilometer area of this region. Its habitat is in highlands with elevations over 1800m and ecotone region between forests and grasslands. Until now the genetic studies has been limited to phylogenic classification and there were no studies on different populations. In this study the genetic diversity of Caucasian black grouse in Iran and Georgia was compared. Sixteen samples were collected from Iranian population at Arasbaran region and finally the DNA of four samples were sequenced retrieving from ND2 Mitochondrial gene. Four sequences from greater caucuses and lesser Caucasus were used For Georgian populations. Results of AMOVA and Fst number showed good genetic differentiation between populations in Iran and Georgia also haplotype and nucleotide diversity were higher compared to Tetrao tetrix which is the sister species for Tetrao mlokosiewiczi . Overall six haplotypes were identified including three haplotypes in Iran and three in Caucasus. The connection between 6 distinguished haplotypes was built using Haplotype Network that showed good genetic structure of this species in Caucasus. There was two clades in Phylogenetic tree including Iranian and Georgian that one sample from Iran was in the Georgian clade. Rogers and Harpending curves for Iran had Multi-peak and Tajima index showed negative values indicating that Caucasian black grouse in Iran didn’t experience the sudden population and may be distributed from Iran to Caucasus. Further studies with more samples from different population can help to further investigate this speculation.in addition for a better conservation of this species, understanding the degree of isolation and connectivity between populations is recommended.
