Cephalaria axillaris Hausskn. ex Bornmüller (1906: 269)

Ranjbar, Massoud & Ranjbar, Zahra, 2017, A taxonomic revision of Cephalaria subgen. Cephalaria sect. Atrocephalae (Caprifoliaceae) from Iran, Phytotaxa 311 (2), pp. 101-138 : 103

1. Cephalaria axillaris Hausskn. ex Bornmüller (1906: 269) .

Type:— IRAN. Prov. Markazi: S Arak, around W Shazand, Rasvand [Rasswand] Mts., 33º 52 ʹ N, 49º 25 ʹ E, 2936 m, August 1899, Th. Strauss, s.n. (B! [B100244788!], lectotype designated by Ranjbar & Ranjbar (2017: 75); isolectotypes JE! [ JE00016246 & JE00016250 ]) .

Perennial, erect, slender to rather robust. Stem 20–40 cm high, single, few-branched, consisting of 1–2 racemes, rather glabrous, thinly white- to purple-striate. Leaves slightly coriaceous, opposite, blades symmetrical, green whe dried, surface rather glabrous or slightly hairy only along the midvein and margins. Lower cauline leaves petiolate (0–2 cm); simple, oblong-lanceolate to oblanceolate in outline, 5–20 × 1–3 cm, acute at apex, serrate to dentate (crenate), 15–50 teeth (apical side straight, basal side concave to flexuous), angle of teeth with reference to the midrib 70º–90º, teeth 1.5–3 mm long, midvein flat adaxially, sharply keeled abaxially, tertiary veins reticulate, oblique. Middle cauline leaves simple to pinnatilobed, oblanceolate to oblong-lanceolate in outline, 10–20 × 1.7–4 cm, with 0–4 lateral segments; lateral segments linear-lanceolate, 1–2.5 × 0.5–0.8 cm, entire, acute at apex; terminal segment larger than lateral ones, lanceolate or oblong to lanceolate, 9–20 × 1.7–4 cm, acute at apex, dentate, 15–35 teeth (apical side straight, basal side flexuous to concave), angle of teeth ca. 50º–90º, teeth 1–5 mm long, midvein flat adaxially, sharply keeled abaxially, tertiary veins reticulate, oblique. Upper cauline leaves simple, oblong lanceolate to linear in outline, 2–10 × 0.5–2 cm, acute at apex, entire to weakly dentate, 20–30 teeth (apical side straight, basal side straight to flexuous), angle of teeth with reference to the midrib none or 45º–70º, teeth 0.8–2 mm long, midvein impressed to flat adaxially, round-keeled abaxially, tertiary veins obliquely reticulate to close together. Peduncle 0–10 cm long, glabrous, with 1–3 capitula on peduncle. Capitula heterocephaloid (axillary and lateral), axillary capitula sessile or subsessile, globose or ovoid, 1.8–2 × 1.5–2 cm in diameter in flower, subradiant, solitary to three at tips of peduncle, lateral capitula pedunclate up to 10 cm, globose or ovoid, 1–1.2 × ca. 1 cm in diameter in flower, subradiant. Involucral bracts in one series, ovate, 5–6 × 3.5–5 mm, green-brown and blackish at apex, tomentose hairs up to 2 mm long, obtuse at apex. Receptacular bracts in six series, rhombic to narrowly ovate to lanceolate, 6–10 × 3–4 mm, spine 1–1.5 mm long, straw-coloured dorsally at base, purple to blackish at apex, and abruptly acute or acuminate at apex, pilose or sericeous, ciliate at margins. Calyx cupuliform, 1–1.5 × 1.5 mm, dark green, pubescent, with irregular teeth 1–1.5 mm long. Corolla 10–11 mm long, yellow, densely covered with appressed hairs outside, stamens slightly longer than corolla, anthers deeply yellow. Involucel 2–2.5 × 1.5 mm in flower, 4-angled, hairy (hairs up to 0.2 mm long), 4 long and 4 short teeth at apex; long teeth ca. 2 mm long, short teeth ca. 0.5 mm long.

Additional specimens examined:— IRAN. Prov. Markazi: Arak, Shahzand, Alim Abad , Alvand Mt. , 2100 to 2800 m, Mozaffarian 56664 ( TARI!) ; Markazi provience: Khane Miran, Sefidkhani mountain, Mozaffarian 56662 ( TARI!) .

Distribution and habitat: — Cephalaria axillaris occurs in Shazand (Rasvand), a mountainous region in Markazi province, and in Alvand Mt. in Hamedan province. The species grows in steppes, stony gravel and rocky places at elevations of 2000–3000 m. It is phytogeographically an Irano-Turanian element.

Taxonomic notes:— Cephalaria axillaris is similar to C. microcephala Boissier (1856: 123) in some characters such as teeth length and angle of lower cauline leaves, shape of middle cauline leaves and number of lateral segments and tertiary veins, involucel teeth, colour and shape of involucral bracts, but it differs from the latter in several characters such as number of teeth in upper cauline leaves margin, length of peduncle and heterocephaloid capitula ( Table 4). Therefore, C. axillaris is considered as a distinct species ( Ranjbar & Ranjbar 2017).