Taraxacum corvinum Kirschner & Štěpánek, 2017

Kirschner, Jan & Štěpánek, Jan, 2017, A revision of Taraxacum sect. Atrata, a dandelion group centred in the Middle Asia, and the problem of Taraxacum brevirostre, Phytotaxa 305 (4), pp. 225-261 : 238-241

publication ID	https://doi.org/ 10.11646/phytotaxa.305.4.1
persistent identifier	https://treatment.plazi.org/id/976B87DC-FFDD-B159-FF15-F9F737C4CFA5
treatment provided by	Felipe
scientific name	Taraxacum corvinum Kirschner & Štěpánek
status

Treatment

6. Taraxacum corvinum Kirschner & Štěpánek View in CoL , sp. nova.

Type: — KAZAKHSTAN. The Zailiyskiy Alatau Range, district of Karasaiskiy Rayon, Almaty, region above the lake of Uľken Almaty (Bolshoe Almatinskoe Ozero), vicinity of the Dzhusaly-Kezen Pass between Pik Almaty (3681 m) and the main summit of Almatynyn-Alatary Mtns. (3954 m), steep gravelly slopes with sparse vegetation SW of the pass, loc. 39, 43° 02‘ 17.1“ N, 76° 56‘ 39.5“ E, 3450 m, 8 Aug 2009, J. Kirschner 3158 ( PRA, no. det. 28130, holotype).

Diagnosis: — Plantae graciles glabrae, foliis anguste linearibus, lobulatis, petiolis et nervo mediano purpureis vel roseis, phyllariis involucralibus exterioribus numero 10–13, linearibus vel lineari-lanceolatis, anguste membranaceomarginatis, floribus luteis, stigmatibus luteis, acheniis sublaevibus, rostro incrassato 2.5–3.7 mm longo.

Description: —Plants slender, usually 6–10 cm tall. Petioles purple, long, narrow, unwinged, leaves deep green with purple to pink-green midvein, glabrous, narrowly linear to narrowly linear-oblanceolate in outline, usually 4–8 (–9) × 0.5–0.8 (–1.1) cm, outer leaves subentire or with 2–4 pairs of patent obtuse teeth, the other leaves pinnatilobed (rarely to pinnatisect), with 2–4 (5) pairs of linear, patent to recurved, straight to hamate lobes usually 2–3 (–4) mm long, terminal segment usually linear, elongated, with a pair of small, patent basal lobules, apex usually obtuse. Scapes brownish green, glabrous, ± overtopping leaves. Capitulum ca. 2–2.5 cm wide. Involucre 6–8 mm wide, rounded at base. Outer phyllaries black-green, appressed, ± not imbricate or slightly so, 10–13, linear-lanceolate to linear, 4.9–5.7 (–7) × (1.5–) 1.8–2.2 mm, border membranous or whitish-membranous, 0.2–0.3 (–0.4) mm wide, with an abrupt transition into the black-green median part, margins glabrous, apex ± flat, often purplish; inner phyllaries usually 10–12 mm long, black-green, callose to ± dark corniculate. Ligules deep yellow, outer ligules flat, striped grey-purple to light blackish purple outside, inner ligule teeth short, pink, purplish or greyish-purplish. Stigmas pure yellow, often with pale purplish pubescence outside. Anthers polliniferous; pollen grains irregular in size. Achenes light greyish stramineous-brown, 3.8–4.2 (–4.6) × 0.8–1.0 mm, body almost smooth or with a narrow zone 0.3–0.4 mm below body apex with scattered minute squamules and/or tubercules, cone not developed, body ± gradually narrowing into thickened beak 2.5–3.7 mm long, ca. 0.2–0.3 mm thick, easily breaking off; pappus ± white, 5–5.5 mm long.—Agamospermous.— Fig. 9A View FIGURE 9 , 10C View FIGURE 10 , 13B View FIGURE 13 .

Ecology and distribution: — Taraxacum corvinum is known from several sites at a single macrolocality below the Dzhusaly-Kezen Pass, the Zailiyskiy Alatau Range, Kazakhstan ( Fig. 5 View FIGURE 5 ). It grows on open wet scree and gravelly slopes with sparse vegetation.

Comparison with other taxa: — Taraxacum corvinum is close to T. goloskokovii but differs from the latter in the outer phyllary characters (they are appressed, not loosely appressed, of narrower shape, with a sharp transition between pale border and the dark middle part) and in shorter achenes.

Specimens examined: — KAZAKHSTAN, the Zailiyskiy Alatau Range, district of Karasaiskiy Rayon, Almaty, region above the lake of Uľken Almaty (Bolshoe Almatinskoe Ozero), vicinity of the Dzhusaly-Kezen Pass between Pik Almaty (3681 m) and the main summit of Almatynyn-Alatary Mts. (3954 m), steep wet gravelly slopes with sparse vegetation SE of the pass, loc. 38, 43° 02‘ 21.2“ N, 76° 56‘ 48.1“ E, 3360 m, 8 Aug 2009, J. Kirschner 3182 ( PRA, no. det. 28193 et dupl. numer.).— Ibidem, steep gravelly slopes with sparse vegetation SW of the pass, loc. 39, 43° 02‘ 17.1“ N, 76° 56‘ 39.5“ E, 3450 m, 8 Aug 2009, J. Kirschner 3157 ( PRA, no. det. 28227) GoogleMaps ; J. Kirschner 3156 ( PRA, no. det. 28191) ; J. Kirschner 3155 ( PRA, no. det. 28192) .