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This study simulates the distributions of 13 endemic and near-endemic genera ( Ammopiptanthus, Sympegma, Iljinia, Elachanthemum, Potaninia, Tugarinovia, Kaschgaria, Sarcozygium, Timouria, Zollikoferia, Stilpnolepis, Synstemon and Tetraena) to indicate areas of plant diversity and conservation importance within the eastern Central Asian desert, and to identify the determinant environmental variables contributing to the spatial distribution patterns. Using known distribution localities and 14 environmental variables, the Maxent and Domain species distribution models were employed to map the patterns of geographic distribution. The power of predictability of the models was tested using the receiver operating characteristic method and the jackknife validation approach, according to the different number of species localities available. The estimated richness and the superimposed potential distributions of 13 genera were used to indicate endemic patterns of distribution. The comparison of Maxent and Domain further identified previously unknown areas of endemism and described the distribution for each taxon. Both observed species occurrence and the species occurrence predicted from the Maxent indicated that the eastern Alashan of Inner Mongolia is the most noticeable endemic area, and the northwestern and northern Tarim Basin of Xinjiang is the secondary center of plant diversity. These regions were then prioritized for conservation importance. Potential evapotranspiration ratio and precipitation seasonality played important roles in driving the observed patterns of endemic distribution. [ABSTRACT FROM AUTHOR]

We studied the arid shrub Amygdalus pedunculata to better understand biogeographic histories and the impact of climate fluctuations during the Quaternary in shaping genetic variation and in northwest China. Three chloroplast DNA intergenic spacers (psbK‐psbI, trnL‐trnF and trnV) were sequenced in 129 individuals from 10 populations across the range of A. pedunculata, and 17 haplotypes were identified, with one haplotype that was distributed across all sampled populations. High levels of total gene diversity (HT = 0.965) and within‐population diversity (HS = 0.669) were identified. Analysis of molecular variance (AMOVA) indicated that most genetic variation occurred within populations. Neutrality tests and mismatch distribution analysis suggested past range expansions of A. pedunculata. As such, A. pedunculata has likely undergone a substantial postglacial range expansion northward and southward along the margins of the northern Yin Mountains and Mu Us Desert, respectively. Principal coordinate analyses, median‐joining network analysis and Beast analysis revealed that 17 haplotypes mainly formed three clusters, corresponding to the Northern (Damao Banner) and Central (Wula Mountains and Guyang County) regions of Inner Mongolia and the Southern region (Bulang Township) in northern Shannxi. The local adaptative differentiation is speculated to have occurred among the three regions mainly resulting from geographical isolation caused by the uplift and extension of the Yinshan Mountains during the Quaternary. [ABSTRACT FROM AUTHOR]