The first phylogenetic analysis of Tetrastigma (Miq.) Planch., the host of Rafflesiaceae

Tetrastigma (Vitaceae) comprises about 95 species widely distributed throughout subtropical and tropical Asia, and extending to Australia. The genus is best known for being the host plants of Rafflesia , with the largest flower in the world, and other members of Rafflesiaceae. The phylogeny of Tetrastigma , however, remains poorly known. Four plastid markers ( atpB ‐ rbcL , psbA ‐ trnH , trnL ‐ trnF intergenic spacers, rps16 intron) were employed to infer the first phylogeny of Tetrastigma . Our sampling included eleven reported host species of Rafflesiaceae, being scattered in seven major clades throughout the Tetrastigma tree. A Templeton test rejected the hypothesis of a single origin of the parasite‐host relationship between Rafflesiaceae and Tetrastigma . Analysis of 114 accessions representing 53 species and four varieties throughout the distributional range of the genus provided robust support for the monophyly of Tetrastigma , yet Tetrastigma was found to be nested within Cayratia . Tetrastigma subg. Palmicirrata from the Sino‐Himalayan region was nested within the large and widely distributed T . subg. Tetrastigma . Two major clades (clades A and F) in our phylogeny correspond to T . sect. Tetrastigma and T . sect. Carinata of subgenus Tetrastigma , respectively.