Fig 1.
Habit and flower detail of Scrophularia lowei (A, C) and S. arguta (B, D).
Scale bar = 2.5 mm.
Table 1.
Studied populations of Scrophularia lowei and S. arguta, including number of individuals studied (N) and haplotype groups (Hap).
Fig 2.
Location of studied populations (coded as in Table 1) of Scrophularia lowei (squares) and S. arguta (circles).
Only populations of S. arguta from its western distribution range and Macaronesia are shown. Population colours indicating the main haplotype as in Fig 5A.
Fig 3.
Molecular dating of Scrophularia based on ITS sequence variation using BEAST.
Core Scrophularia includes all analysed Scrophularia species except S. arguta and S. lowei; the complete tree is shown in S1 Fig. Clade posterior probabilities ≥ 0.90 are indicated above branches. The 95% posterior density distribution of node ages is superimposed in red on branches with a PP ≥ 0.90. Calibration points used in the analyses are indicated (A, 26.77 ± 4.27 million years ago [Ma]; B, 15.92 ± 3.29 Ma; C, 10.20 ± 2.36 Ma). Scrophularia lowei sequences are indicated by the light green background. The scale is in millions of years. Abbreviations: Pleist., Pleistocene; Plioc., Pliocene; Mid. Mioc., Middle Miocene. Colours on the right correspond to the main haplotype indicated as in Fig 5A.
Fig 4.
BEAST chronogram of Scrophularia lowei and S. arguta based on (A) nuclear (ITS/ETS) and (B) chloroplast (psbA–trnH/psbJ–petA) DNA sequences.
Black and red numbers above and below branches are posterior probability (PP) and maximum likelihood (ML) bootstrap (BS) values, respectively. Only values corresponding to a PP ≥ 0.90 and a ML BS ≥ 65 are shown. The light green background indicates S. lowei populations. Colours on the right correspond to the main haplotype indicated as in Fig 5A.
Fig 5.
TCS statistical parsimony network of chloroplast DNA haplotypes found in Scrophularia arguta and S. lowei in the matrix considering only complex gaps as mutational steps (A) and the matrix including all unambiguous mutations (B, all haplotypes; C, only haplotype G).
In these analyses, gaps were coded as single mutations. Dashed lines indicate connections to the outgroup (S. megalantha in A and B; haplotype E1 in C). Haplotypes found in S. lowei populations are indicated by solid margins. Small circles represent inferred mutational steps. The size of a given haplotype symbol indicates the relative number of populations harbouring that haplotype. Haplotype abbreviations (A, B) and population codes (C) are the same as in Table 1.
Table 2.
Analysis of molecular variance (AMOVA) of nuclear DNA (nDNA) and chloroplast DNA (cpDNA) between Scrophularia arguta and S. lowei.