Abstract: The Saururaceae family, a member of remaining paleoherbs with medicinal value, shows typically East Asian-North American disjunction. However, plastome features of this family have not been clarified, which has severely hindered the utilization of Saururaceae plants and understanding of the origin, early evolution and distribution pattern of angiosperm. Hence, we conducted comprehensively plastome comparative analyses for Saururaceae, including three genera of four genera. The results showed that plastomes of Saururaceae were highly conserved in terms of genomic structure, gene content and arrangement. Nevertheless, their genomic sizes varied remarkably, which may be caused by the insertion/deletion of bases. In addition, two high variable regions (rps16-trn Q-UUG and rpl 32-trn L-UAG) were selected among plastomes that can serve as candidate specific barcoding for species identification of Saururaceae and three SSR types (tri-nucleotides, penta-nucleotides and hexa-nucleotides) were provided as specific molecular makers to recognize Saururus chinensis. Generally speaking, our results provide new insights into species evolution and identification of Saururaceae.

Key words: Saururaceae, plastome comparison, simple sequence repeat, high variable fragment selecting