Centaurea tabriziana Ranjbar & Heydari, 2015

Ranjbar, Massoud & Heydari, Razayeh, 2015, A contribution to Centaurea sect. Phaeopappa (Asteraceae, Cardueae) in Iran, Phytotaxa 201 (1), pp. 79-86 : 82

Centaurea tabriziana Ranjbar & Heydari , sp. nov. Figs. 2 , 3 .

Diagnosis:—The new species is closest to Centaurea phaeopappa in habit, shape of achenes and pappus and colour of flower, but differing in the median cauline leaves decurrent (vs. not decurrent), median and upper cauline leaves pinnatisect to lyrate (vs. pinnatipartite to pinnatisect), upper cauline leaves 5–10 × 0.5–3 cm (vs. 4–6 × 0.2–0.4 cm), upper cauline leaves segments 3–5 pairs (vs. simple), peduncle up to 5 mm long (vs. sessile or 7–10 mm long), involucres 30–40 mm (vs. ca. 20 × 25 mm), median appendages (fimbriae and spine included), 15–22 mm (vs. 7–10 mm) long.

Type:— IRAN. Prov. East Azarbayejan: Tabriz to Varzaghan between Hiq and Zaqan Abad, 38°22’57.14’’, 46°43’ 0.94’’, 1810 m, 26 April 2013, Ranjbar 35650 (holotype BASU!, photo W).

Perennial 50–55 cm tall, with woody rhizome, covered with abundant brown fibrous remains of petioles of the previous year. Stem erect, often branched above, sometimes branched in median to upper parts, cylindrical, rigid, 2–6 mm in diam. at the base, densely floccose-tomentose. Leaves almost pinnatipartite or lyrate. Basal and lower leaves distinctly large, 14–29 cm long, short-petiolate (sessile or on petioles up to 8 mm long), pinnatipartite to pinnatisect, segments in 6–20 pairs, narrowly lanceolate or lanceolate-linear or narrowly elliptic, 2–5 mm wide, sometimes falcate-curvate, acuminate at apex. Median cauline leaves sessile or decurrent, 11–15 cm long, pinnatisect, segments in 6–15 pairs, lanceolate-linear or linear, 3–8 mm wide, acuminate at apex. Upper cauline leaves decurrent, smaller, 5–10 cm long, pinnatifid or lyrate, segments in 4–8 pairs, linear or linear-lanceolate, 5–15 mm wide, sometimes undivided, acuminate or elongated into a mucro, usually longer than capitula. Capitula 2–6 on peduncles 5 mm long or sessile, solitary at end of branches, involucres oblong, 1.5–2 × 3–4 mm. Phyllaries multiseriate, imbricate, coriaceous, greenish, smooth and glabrous. Outer phyllaries ovate-oblong, 4–10 × 3–8 mm, appendages 12–15 × 5–14 mm (fimbriae and spine included). Median phyllaries oblong, 12–15 × 7–10 mm, appendages 15–22 × 10–12 mm (fimbriae and spine included). Inner phyllaries oblong or oblong-lanceolate, 18–20 × 3–6 mm, sometimes striate, appendages 3–6 × 3–5 mm (fimbriae and spine included). Appendages concealing a major part of phyllaries, triangular or long-triangular, membranouscoriaceous, brownish black in central part or completely brown, sometimes shortly decurrent on crenate margins, innermost lacerate, fimbriae whitish, narrowly triangular, distinct, sometimes subreflexed, numerous, 10–16 on each side, 1–5 mm long, spine sometimes slender, brownish, 7–10 mm long, much longer than the nearest fimbriae. Flowers yellow; central flowers hermaphrodite, 28–33 mm long, corolla 13–15 mm long, 5-lobed, lobes acute and ± equal, ca. 6 mm long; peripheral flowers sterile, finely dissected, not radiant, 4–5-lobed, limb lobes linear, 4–5 mm long. Achenes oblong, 7–8 mm long, 2.5–3 mm wide, brown, glabrous, smooth or striate-costate, compressed, hilum lateral, 0.8–1 mm long, glabrous, whitish. Pappus multiseriate, persistent, scabrous, brownish, 15–16 mm long.

Etymology: The specific epithet refers to Tabriz, the capital of East Azarbayejan province, near which the new species was found.

Distribution and habitat:— Centaurea tabriziana is distributed in Kasabe mountains in East Azarbayejan Province near Tabriz, NW Iran. This species is an Irano-Turanian element collected in the dry-steppe zone and on stony slopes of mountainous regions, growing in elevations higher than 1800 m.

Relationships:— Centaurea tabriziana is similar to C. phaeopappa , endemic to NW Iran, in flower colour, and length of achenes and pappus, but differ from this species in its median cauline leaves decurrent (vs. not decurent), median and upper cauline leaves pinnatisect to lyrate (vs. pinnatipartite to pinnatisect), upper cauline leaves 5–10 × 0.5–3 cm (vs. 4–6 × 0.2–0.4 cm), upper cauline leaves segments 3–5 pairs (vs. simple), peduncle up to 5 mm long (vs. sessile or 7–10 mm long), involucers 30–40 mm (vs. ca. 20 × 25 mm), median appendages (fimbriae and spine included) 15–22 mm (vs. 7–10 mm) long.

Figures

FIGURE 2. Centaurea tabriziana Ranjbar & Heydari (Ranjbar35650, BASU).

FIGURE 3. Centaurea tabriziana Ranjbar & Heydari (Ranjbar35650, BASU). A. close up of capitule. B. upper leaves. C & D. median leaves. Scale A–C = 2 cm.