Centaurea sennikoviana Negaresh & Kaya (2015: 321)

Negaresh, Kazem & Rahiminejad, Mohammad Reza, 2018, A revision of Centaurea sect. Cynaroides (Asteraceae, Cardueae-Centaureinae), Phytotaxa 363 (1), pp. 448-450 : 448-450

30. Centaurea sennikoviana Negaresh & Kaya (2015: 321) . Type:— TURKEY. C5 Niğde: Çamardi, Nazmılı , high plateau foot, s.c. 495 (holotype ISTE!, isotype HUI!). ( Fig. 69 )

Biennial plants, with thick taproot, whole plant usually greenish, ca. 45 cm tall; collum with fibrous remnants of petioles from previous year. Stem erect, simple, ca. 3 mm in diam. at base, cylindrical, with thin yellowish striations, sparsely leafy throughout, lower part ± densely covered with hirsute-articulate hairs, up to 3 mm long, median part loosely covered with arachnoid hairs mixed with scattered hirsute hairs, upper part densely covered with arachnoid hairs. Leaves rigid (on drying), loosely covered with hirsute-articulate hairs, denser along midrib, up to 1 mm long. Basal and lower cauline leaves petiolate, cordate, 16–24 × 6–7 cm, margins entire, sometimes remotely denticulate, acute at apex. Median cauline leaves petiolate or sessile, simple, triangular-lanceolate or subpandurate, 10–13 × 3.5– 5.5 cm, decurrent, up to 30 mm along stem, or with basal auricles, margins entire or remotely denticulate, acute or subacuminate at apex. Upper cauline leaves increasingly smaller, sessile, simple, narrowly oblong or linear, 2–6 × 0.5–2 cm, loosely covered with arachnoid hairs, broadly decurrent, up to 50 mm along stem, margins entire, rarely remotely denticulate, acuminate or mucronate at apex. Capitula few, 2 to 4, arranged in racemes, with short peduncles (1–2 cm long). Involucres ovoid-cupuliform, 25–35 × 22–32(–35) mm. Phyllaries multiseriate, yellow-greenish in sicco, imbricate, coriaceous-scarious, densely short-floccose, especially along margins. Appendages small, concealing part of phyllaries only, triangular, chartaceous or membranous, pale brown; cilia 10–14 on each side, 2–3 mm long, membranous and whitish; spine 2–5 mm long, slightly longer than adjacent cilia. Outer phyllaries broadly oblong, 3–5 × ca. 5 mm, appendages 4–5 × 4–8 mm (including cilia and spine), narrowly decurrent. Median phyllaries broadly ovate, 7–10 × 7–8 mm, appendages 7–10 × 10–12 mm (including cilia and spine). Inner phyllaries oblong-linear, 15–20 × 3–7 mm, appendages lacerate or pectinate, 4–6 × 3–7 mm. Flowers pink; central florets hermaphroditic, 25–30 mm long, corolla ca. 18 mm long, 5-lobed, lobes 5–6 mm long, with purple nerves; peripheral florets sterile, slightly shorter than central ones, numerous (ca. 15 in each capitulum) and conspicuous, finely dissected, not radiant, 4–5-lobed, limb lobes filiform, 5–6 mm long. Achenes oblong, 6–7 mm long, 2.5–3 mm wide, smooth, pale brown or whitish to pale brown, rounded at apex, glabrescent; insertion areole lateral, yellow, 0.8–1 mm long. Pappus double, persistent, multiseriate, scabrous, whitish or pale brown, 8–9 mm long, bristles of inner rows much shorter than others, ca. 2 mm long.

Taxonomic and distribution remarks: — Centaurea sennikoviana is a very rare endemic to Niğde Province, S Turkey ( Fig. 68 ). It is an Irano-Turanian element, and grows on high plateau foot. It closely resembles C. aladaghensis in its habit .

Chromosome numbers: —Unknown.

Figures

FIGURE 68. Distribution of Centaurea sclerolepis (circles), C. sennikoviana (squares), and C. shahuensis (triangles).

FIGURE 69. Centaurea sennikoviana Negaresh & Kaya (s.c. 495, ISTE). A. habit. B. capitula. C. achene with pappus. Scale A = 2 cm, B = 1 cm, C = 5 mm.