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ISRAEL JOURNAL OF PLANT SCIENCES 51

Figure 3. Discriminant analysis based on the 26 considered morphological characters with groups corresponding to the 17 populations. Axis
1: Eigenvalue 18.783, % variance 59.37; Axis 2 Eigenvalue 4.5068, % variance 14.25. C: C. busambarensis; ^: C. panormitana subsp. todaroi;
■: C. panormitana subsp. umbrosa; : C. panormitana subsp. panormitana; –: C. saccensis;: ~ C. panormitana subsp. seguenzae; ~: C. erycina;

: Centaurea sp. from Favignana.

2016). The range of each continuous numerical char- variation are: length of rosette leaves, width of
acter was represented using box-and-whiskers plots upper stem leaves, capitulum width, median phyl-
(Electronic Supplement 2, supplemental material). lary length, and pappus length.

Centaurea aegusae Domina, Greuter & Raimondo, sp.
Results nova (Figure 4)

The PCA (Figure 2) discriminates clearly Centaurea sac- Description. Perennial, up to 70 cm tall, rosette-form-
censis, the population from Favignana, C. panormitana ing. Stem erect, white-tomentose, with several
subsp. panormitana, and C. busambarensis; the other branches arising in the distal half of the stem. Rosette
taxa show partial overlap. The DA (Figure 3) shows the leaves 2 pinnatisect, white-tomentose to arachnoid,
same three taxa as clearly distinct, but the overlap
6–20 £ 3.5–8 cm, with 3–6 pairs of lobes of 10–30 £
between C. panormitana subsp. panormitana, C. ery- 3.5–5 mm, lacking pinnules in between. Cauline leaves
cina and C. panormitana subsp. seguenzae is lesser; 2-pinnatisect, with regular lobes, white-tomentose,
only C. panormitana subsp. umbrosa and C. panormi- 4–7 £ 1.5–3 cm. Leaves of branches 1-pinnatisect, 10–
tana subsp. todaroi overlap significantly. The initial 12 £ 6–12 mm. Capitula 2–7 per branch. Peduncles
hypothesis, that the plants from Favignana are suffi- 1.5–2 mm wide, with sparse leaves. Involucre ovoid,
ciently distinct from the other taxa to deserve recogni- 8–15 £ 11–16 mm. Phyllaries lanceolate, tomentose
tion at the species level, is thus confirmed. to arachnoid. Phyllary appendages dark brown, fimbri-
Of the individuals, 97.75% were correctly classi- ate. Fimbriae 5–7 on each side, 1.5–2 mm long. Florets
fied by DA to their apriori assigned taxon (or pinkish violet. Achenes gray, 3–3.5 £ 1–1.5 mm. Pap-
90.45% with the Jackknife method; see Osuji et al. pus 3–3.5 mm long.
2013). Univariate analysis of all continuous morpho-
logical characters (Electronic Supplement 2) shows Holotype. Sicily, Island of Favignana, Mt. Santa
little variation. There are outlier values in the overall Caterina, Scindo Passo, 37.920730 N, 12.307299 E,

plant height, capitulum width, and length of median 100 m a.s.l., maritime carbonate cliffs, 25/5/2016, G.
phyllaries. The characters that show the highest Domina (PAL). Isotypes: PAL, PAL-Gr, FI, RO, B.