Complete plastid genome of Suriana maritima L. (Surianaceae) and its implications in phylogenetic reconstruction of Fabales.

The present paper reports for the first time the characteristics of the complete plastid genome of Surianaceae (Suriana maritima L.) in the order Fabales. The circular complete plastid genome is 163,747 bp in length with a typical quadripartite organization containing 115 unique genes, of which 80 are protein-coding genes, 31 tRNA genes and four rRNA genes. The plastid genome of S. maritima is characterized by absence of intron in the atpF gene, which has never been reported for any other species of the Fabales. The gene content and their orders in the plastid genome of Surianaceae are similar to the basal lineages of the legume family (Cercidoideae, Detarioideae) and Quillajaceae, supporting a likely common ancestor for the three families. Phylogenetic analysis supported the sister relationship between Surianaceae and Leguminosae, with strongly supported by Bayesian method and moderately supported by likelihood method. The complete plastid genome of Surianaceae could provide potential benefit in resolving the long-standing unresolved interfamily relationships of Fabales when a more comprehensive sampling from Polygalaceae and Leguminosae is available for future studies.