Is the genus Cissus (Vitaceae) monophyletic? Evidence from plastid and nuclear ribosomal DNA

The trnL (UAA) intron and ITS1 region were sequenced to investigate relationships among the five genera of Vitaceae present in Australia relative to Vitis. Congruent results, were obtained between separate and combined data sets, with all major clades being shared among trees. All bootstrap consensus trees obtained from single sequences or combined analysis strongly suggest that Cissus is polyphyletic, corroborating the morphological inconsistencies reported previously., p Cissus opaca and Clematicissus angustissima consistently grouped in a common clade. A further four taxa (C. antarctica, C. hypoglauca, C. oblonga, and C. sterculiifolia) also grouped within a clade disjunct from the main Cissus clade. Our results suggest that these five species currently classified as Cissus should be segregated from the genus. Of further interest is the close relationship between Cayratia and Tetrastigma. Overall, the results presented provide new insights into the relationships within a number of Vitaceae genera and suggest directions for future studies

A new phylogenetic tribal classification of the grape family (Vitaceae)

Vitaceae (the grape family) consist of 16 genera and ca. 950 species primarily distributed in tropical regions. The family is well-known for the economic importance of grapes, and is also ecologically significant with many species as dominant climbers in tropical and temperate forests. Recent phylogenetic and phylogenomic analyses of sequence data from all three genomes have supported five major clades within Vitaceae: (i) the clade of Ampelopsis, Nekemias, Rhoicissus, and Clematicissus; (ii) the Cissus clade; (iii) the clade of Cayratia, Causonis, Cyphostemma, Pseudocayratia, Tetrastigma, and an undescribed genus Afrocayratia; (iv) the clade of Parthenocissus and Yua; and (v) the grape genus Vitis and its close tropical relatives Ampelocissus, Pterisanthes and Nothocissus, with Nothocissus and Pterisanthes nested within Ampelocissus. Based on the phylogenetic and morphological (mostly inflorescence, floral and seed characters) evidence, the new classification places the 950 species and 16 genera into five tribes: (i) tribe Ampelopsideae J.Wen & Z.L.Nie, trib. nov. (47 species in four genera; Ampelopsis, Nekemias, Rhoicissus and Clematicissus); (ii) tribe Cisseae Rchb. (300 species in one genus; Cissus); (iii) tribe Cayratieae J.Wen & L.M.Lu, trib. nov. (370 species in seven genera; Cayratia, Causonis, Afrocayratia, Pseudocayratia, Acareosperma, Cyphostemma and Tetrastigma); (iv) tribe Parthenocisseae J.Wen & Z.D.Chen, trib. nov. (ca. 16 spp. in two genera; Parthenocissus and Yua); and (v) tribe Viteae Dumort. (ca. 190 species in two genera; Ampelocissus and Vitis)