Page 3 - Domina_alii_2017

50 G. DOMINA ET AL.

Figure 1. Distribution of the sampled populations.

7. Upper stem leaves, width Three qualitative characters
8. Apical lobe of rosette leaves, length
24. Leaves shape (pinnatisect/bipinnatisect)
9. Apical lobe of rosette leaves, width
25. Leaves indumentum (glabrous/subglabrous/
10. Lateral lobes of rosette leaves, length
tomentose)
11. Lateral lobes of rosette leaves, width
26. Fimbriae color (pale/dark)
12. Capitula, length
13. Capitula, width
A principal component analysis (PCA) and a discrimi-
14. Median phyllaries, length
nant analysis (DA) were performed, following Boyd
15. Median phyllaries, width
(2002), Peruzzi et al. (2015), and Giovino et al. (2015).
16. Appendage fimbriae of middle phyllaries, length
The PCA (Figure 2) was based on logarithmic values of
17. Cypsela, length
continuous quantitative characters. The DA, with the
18. Cypsela, width
individuals a priori assigned to the eight postulated
19. Pappus, length
taxa, was performed on quantitative and qualitative
characters (Figure 3). Each continuous quantitative
Four discrete quantitative characters character was also subjected to univariate analysis
20. Lobes of lower steam leaves, number (ANOVA or a Kruskal–Wallis test, with corrections for
21. Intermediate pinnulae of lower stem leaves, number multiple comparisons, Pearson correlation coeffi-
22. Capitula per stem, number cients, Tukey HSD test, and Bonferroni, respectively),
23. Appendage fimbriae of middle phyllaries, number using PAST version 3.12 (Hammer et al. 2001; Hammer

Figure 2. Principal component analysis based on the 19 continuous morphological characters, with groups corresponding to the 17
populations. PC1: Eigenvalue 0.832, % variance 59.93; PC2: Eigenvalue 0.136, % variance 9.83. C: Centaurea busambarensis; ^: C. pan-
ormitana subsp. todaroi; ■: C. panormitana subsp. umbrosa; : C. panormitana subsp. panormitana; –: C. saccensis; ~: C. panormitana
subsp. seguenzae; ~: C. erycina;
: Centaurea sp. from Favignana.