Centaurea aeolica Gussone ex Lojacono (1903: 136)

Brullo, Salvatore, Cambria, Salvatore, Crisafulli, Alessandro, Tavilla, Gianmarco & Sciandrello, Saverio, 2021, Taxonomic remarks on the Centaurea aeolica (Asteraceae) species complex, Phytotaxa 483 (1), pp. 9-24 : 10-16

1. Centaurea aeolica Gussone ex Lojacono (1903: 136) ( Figs. 1 , 4A , 7A, C )

≡ Centaurea cineraria var. aeolica (Gussone ex Lojac.) Fiori in Fiori & Paoletti (1904: 334) ≡ Acosta aeolica (Guss. ex Lojac.) Holub (1974: 226) ≡ Centaurea aplolepa subsp. aeolica (Guss. ex Lojac.) Dostál (1976: 202) .

Type:— ITALY. Sicily. In insula Lipari, rara et localis, Junio , MLP. (manu Lojacono ) (PAL 10639!, lectotype designated by Cela Renzoni & Viegi (1983: 137); isolectotypes G-BU, PAL 10636, 10637, 10638) .

Description: —Perennial herb with a woody rootstock. Stems erect, striate, with greenish-grey tomentum, 20–60 cm tall and 2–4 mm in diameter, simple, leafy. Leaves tomentose, greenish-grey; basal leaves usually on short sterile branches, more or less petiolate, 1–2–pinnatisect, 7–30 cm long × 1–10 cm, loosely laciniate, with laciniae linearlanceolate to linear, 1–10 cm long, 1–2.5 mm wide, apex acute, shortly mucronate; cauline leaves shortly petiolate to subsessile, ovate to ovate-lanceolate in outline, 1–2–pinnatisect, 1–12 cm long, with laciniae 1–8 cm long, 0.5–3 (6) mm wide, apex acute, shortly mucronate. Capitula arranged in terminal racemes, ovoid, 13–16 mm long, 8–12 mm in diameter; phyllaries imbricate up to 70, powdered, dorsally convex, usually 7-nerved, with terminal appendages whitish, triangular, denticulate, 1–2 mm long (up to 2.5 in the innermost phyllaries), 0.8–2 mm wide, with teeth 0.05– 0.3 mm long; outer phyllaries ovate 4–5.5 × 1.8–2.7 mm; median phyllaries ovate-lanceolate 6–10 × 2.4–3.2 mm; inner phyllaries linear-lanceolate 11–12.5 × 1.2–2 mm. Florets purplish-pink; ray florets sterile, 18–19 mm long, with lobes unequal, 4–5.8 mm long; disc florets fertile, 15–16.5 mm long, with lobes equal, 3.5–4.3 mm long; stamens 16–16.5 mm long, with filaments 10–11 mm long, fused below, free and hairy above, anthers 6 mm long. Style 15 mm long, ciliate at apex; stigmatic branches 2 mm long. Achenes oblong, 3.4–3.7 × 1.4–1.6 mm, sparsely villous, brownish, coronula large, straw-coloured, with several irregular straw-coloured longitudinal ridges; pappus biseriate, brownish below and whitish above, outer series 0.4–0.8 mm long, inner series 1.6–2 mm long.

Etymology: —The specific epithet derives from Aeolian archipelago (latin aeolicus) where this species grows.

Phenology: —The species flowers from May to July and fruits from June to July.

Distribution and ecology: —Basing on herbarium specimens and literature data ( Gussone 1844; Ferro & Furnari 1970), Centaurea aeolica occurs in the almost all the volcanic islands and islets of the Aeolian archipelago, except Filicudi ( Fig. 5 ). Usually, it is localized in the shrublands as well as in the rupestrian stands.

Conservation status: —According to Conti et al. (1997) and Orsenigo et al. (2018), C. aeolica was assessed as Least Concern (LC).

Taxonomic notes: —Within the C. cineraria group, C. aeolica is taxonomically quite isolated, differentiated from the other species of this group by its laciniate leaves, as well as the capitula with phyllaries having hyaline uncoloured and slightly denticulate terminal appendages. Conversely, the other species have less incised leaves with shorter and wider segments, while their capitula have phyllaries usually with well-developed and long fimbriate, blackish or dark brown appendages.

Specimens examined: — ITALY. Sicily: Isole Eolie, Panarea, 24 June 1982, S. Brullo s.n. (CAT 2219!, 2237!, 2238!, 2239!); ibid. Panarea, 28 May 1983, S. Brullo s.n. (CAT 2228!, 2236!, 2244!, 2245!); ibid. Lipari, Pomiciaro, 25 April 1982, S. Brullo s.n. (CAT 2217!); ibid. Lipari, Cava di Pomice, 13 May 1972, S. Brullo s.n. (CAT 2222!); ibid. Lipari, 24 April 1982, S. Brullo s.n. (CAT 2234!); ibid. Lipari, Quattrocchi, 28 May 1969, F. Furnari s.n. (CAT 2242!); ibid. Lipari, Cava Pomice, 30 May 1969, F. Furnari s.n. (CAT 2243!); ibid. Salina, Malfa, 2 April 1970, S. Brullo s.n. (CAT 2221!); ibid. Salina, Pollara, 30 April 1982, S. Brullo s.n. (CAT 2232!, 2235!); ibid. Alicudi, 14 June 1980, S. Brullo s.n. (CAT 2224!); ibid. Alicudi, 31 May 1980, S. Brullo s.n. (CAT 2223!); Messina, Isole Eolie, Lipari, Valle Muria, by the way to “ Spiaggia Valle Muria”, garrrigue, 100 m, 30 May 2008, A. Hilpold V-1179 (BC-947311); ibid. Lipari, S of Cava del Pomice, 1 km N Canneto, by the road to Porticello, rocks, 60 m, 30 May 2008, A. Hilpold V- 1181 (BC-947312); Italien, Messina, Insel Stromboli, Collection route see map, 450-900 m, May 2000, R. Albert & M. Watzka 398 (W2017-0004366); Lipari, In rupibus vulcanicis maritimis, May 1881, Borzì s.n. (MS); Lipari, Costa del Cappero, In rupibus vulcanicis maritimis, June 1882, Lojacono s.n. (FI); Isole Eolie, Lipari, presso la Cava di Pomice, “locus classicus”, la pianta è comune, 24 May 1972, Garbari & Cela Renzoni s.n. (PI). Lipari, Spiagge Bianche, 6 August 2020, G. Tavilla, V. Grasso, D. Azzaro, M. Di Stefano s.n. (CAT!); ibid. Lipari, Punta della Castagna, 6 August 2020, G. Tavilla, V. Grasso, D. Azzaro, M. Di Stefano s.n. (CAT!).

Figures

FIGURE 1. Centaurea aeolica. A. Habit. B. Capitulum. C. Appendages of the phyllaries. D. Ray sterile floret. E. Disc fertile florets. F. Stamen. G. Stygma. H. Achenes with pappus. Illustration by S. Brullo based on living material coming from Lipari collected by Tavilla et al. (CAT!).

FIGURE 4. Variability of the phyllaries in Centaurea aeolica (A), Centaurea pandataria (B) and Centaurea phalacrica (C). Illustration by S. Brullo based on living material coming from the same locality as quoted in Fig. 1, 2, 3 (CAT!).

FIGURE 5. Geographical distribution of Centaurea aeolica (blue dots), C. pandataria (red dot) and C. phalacrica (green dot) based on herbarium materials and literature data.

FIGURE 7. A. Basal leaves of C. aeolica from Lipari island. B. Basal leaves of C. pandataria from Ventotene island. C. Capitulum of C. aeolica from Lipari island. D. Capitulum of C. pandataria from Ventotene island. (Photos by G. Tavilla).