Fig. 1

Maximum likelihood tree of Ludwigia sect. Isnardia inferred from the nuclear ITS region. The arrows indicate the crown nodes of Isnardia. Sample numbers (Additional file 1), ploidy levels (Table 1), and genome types (Table 1) are shown right after the taxa. Numbers at nodes show the bootstrapping values (bs) / posterior probabilities (pp) only when the bs at nodes are greater than 50 or pp at nodes are greater than 0.70. The A, M₁M₂, F₁F₂, and D clades are indicated. The scale bar denotes the branch length