Psephellus congestus (Wagenitz) Wagenitz

Yousefi, Zohreh, Negaresh, Kazem & Kaya, Yusuf, 2021, A taxonomic study on Psephellus sect. Amblyopogon (Asteraceae, Cardueae- Centaureinae), Phytotaxa 494 (3), pp. 273-288 : 276-277

1. Psephellus congestus (Wagenitz) Wagenitz in Wagenitz & Hellwig (2000: 37). ( Figs. 1 and 2 )

Centaurea reuteriana Boissier (1844: 18) var. pinnatisecta Parsa (1948: 201) . Centaurea congesta Wagenitz (1980: 405) . Type:— IRAN. Prov. East Azerbaijan: Nr. salt lake 30 miles SE of Tabriz, ca. 1830 m, 7 May 1929, Cowan & Darlington 752 (holotype K000794266!).

Perennial plants, with long and stout woody rootstock forming a nearly large cushion with numerous rosettes of leaves, stemless or nearly so, whole plant usually green. Leaves petiolate, coriaceous, densely covered with grayishtomentose hairs, pinnatisect, 8–10 cm long; segments in 5–10 pairs, terminal segment equal to lateral ones, linearlanceolate or lanceolate, 2–5 mm wide, decurrent along the rachis, smooth or denticulate at margins, acute or acuminate at apex, rarely lobed; sometimes lyrate or pinnatipartite. Capitula numerous, 10–30-cephalous, solitary on sessile peduncles; involucres ovoid, 25–30 × 17–20 mm. Phyllaries multiseriate, coriaceous, imbricate, smooth, green, glabrous. Appendages small-sized, concealing partly of phyllaries only, dark brown, narrowly triangular, 1.5–2 mm wide (excluding cilia), distinctly decurrent, irregularly fimbriate, never with a spine; fimbria dark brown, numerous, 12–18 on each side, 1–2 mm long; mucro ± equal to adjacent fimbria. Flowers pink; central florets hermaphroditic, numerous, 14–16 mm long, corolla 9–12 mm long, 5-lobed, lobes 4–5 mm long, stigma slightly exserted from corolla; peripheral florets 24–26 mm long, much longer than central ones, scarcely radiant, with staminodes, corolla 16–18 mm long, 4-lobed, limb lobes lanceolate, 8–10 mm long. Achenes oblong, 7–8 mm long, smooth, rounded at apex, glabrous. Pappus multiseriate, straw-coloured, deciduous, scabrous, as long as achenes, ca. 8 mm long, bristles of inner rows much shorter than outer, ca. 1.5 mm long.

Distribution: — Psephellus congestus is a rare endemic to East Azerbaijan Province, NW Iran ( Fig. 3 ).

Ecology: — Psephellus congestus is an Irano-Turanian element, and grows on grassland and meadow-steppe slopes, at elevations of 1800–2000 m.

Taxonomic notes: — Psephellus congestus is a distinct species without close relatives. Its morphological characters that are very distinctive as: 1. plant forming a nearly large cushion with numerous capitula (10–30-cephalous); 2. appendages dark brown, distinctly decurrent, irregularly fimbriate; 3. the longest pappus (ca. 8 mm long).

Selected specimens examined:— IRAN. Prov. East Azerbaijan: Zanjan-Mahneshan road, between Ghar-e Dash and Tazkh Kend villages, 1900–2000 m, 10 May 2017, Jarchi & Negaresh 266 ( KHAU!) ; Jarchi & Negaresh 267 ( KHAU!) ; Mianeh, S Kuh-e Boz-Ghosh, from Varnakesh village , Mozaffarian 93254 ( TARI!) ; Mianeh, Boz-Ghosh Mt., above Charan village , 2500 m, 5 June 2012, Noroozi 2681 ( W!) ; inter Zanjan et Mianeh, 1800 m, Sabeti 3879 ( IRAN!) .

Figures

FIGURE 1. Psephellus congestus (Wagenitz) Wagenitz (Cowan & Darlington 752, K).

FIGURE 2. Psephellus congestus (Wagenitz) Wagenitz (Jarchi & Negaresh 266, KHAU). A. plant and habitat. B. close up of a capitulum. Scale A = 2 cm, B = 1 cm.

FIGURE 3. Distribution of Psephellus congestus (squares) and P. incanescens (circles).