Taraxacum peschkovae Kirschner & Štěpánek, 2025

Kirschner, Jan, Štěpánek, Jan & Buryy, Vladimir V., 2025, Towards a revision of Taraxacum sect. Borealia (Compositae, Crepidinae) in Siberia and the continental Far East, with special reference to the dandelions of the Altai and Kamchatka, Phytotaxa 679 (1), pp. 1-147 : 41-43

12. Taraxacum peschkovae Kirschner & Štěpánek , sp. nov.

Type:—[ Russia, Altai Republic] USSR, Sibiria austro-occid., montes Altaj, pars Ajgulakskij chrebet, distr. Usť-Ulagan , in pratis haud procul a lac. Mjortvyje Ozera, ad clausam mont. Ulaganskij Pereval, ca. 1850–1900 m, 2 Jul 1988 , J. Kirschner , cultivated as T 151 ( PRA, no. det. 35855, holotype) .

Etymology:—Named in honour of Galina Alexandrovna Peschkova [Галина Александровна Пешкова] (1930–2018), an outstanding Irkutsk and Novosibirsk botanist and an expert in the flora of south-central Siberia.

Diagnosis:—Species spectabilis, foliis semper indivisis irregulariter dentatis, petiolis late vel anguste alatis, stigmatibus atro-viridibus, phyllariis involucralibus exterioribus laxe adpressis, lanceolatis, apice longissime atro-cornutis, et acheniis crassis, pyramide crassa, conica notabilis.

Plants relatively small but of robust appearance, ca. 8–13 cm tall. Petiole often suffused greyish purple, broadly to narrowly winged, sparsely arachnoid, tunic absent. Leaves deep green to dark green, sparsely arachnoid, later glabrescent, with brownish-purplish mid-vein, ± oblanceolate in outline, usually 7–9 × 2.0– 2.5 cm, not divided, irregularly dentate (little teeth mixed with short, patent triangular teeth, sometime also short lobules, apex of leaf blade ± acute. Scapes brownish green, often suffused purplish, sparsely arachnoid, ± equalling leaves, growing from outside the leaf rosette. Capitulum yellow, up to ca. 3.0– 3.5 cm wide. Involucre dark olivaceous-green, 9–10 mm wide and broadly rounded at base. Outer phyllaries usually 12–16, ± loosely appressed, ± not imbricate, ± lanceolate, 7.5–10 mm long including horns, 2.0– 2.8 mm wide, border membranous, 0.2–0.3 mm wide, with a very gradual and indistinct transition into a green zone, with a blackish green central band 0.3–0.5 mm wide, margin ± not ciliate, apex with extraordinarily long, either perpendicular or suberect, blackish green or blackish purple horns usually (1–) 3–5 mm long; inner phyllaries 11–14 mm long, usually not coalescing, corniculate or with black horns to 2 mm long. Outer ligules ± flat to canaliculate, narrow, striped light greyish pink outside, teeth black-purple, inner ligule teeth blackish purple. Stigmas greyish green, with dense black pubescence outside. Pollen present, pollen grains irregular in size. Achenes light greyish stramineous-brown, (3.5–) 3.9–4.3 × (0.9–) 1.0– 1.3 mm, body subsparsely to subdensely covered with short spinules in upper 1/4–1/3, subgradually to gradually narrowing into a thick, conspicuously conical cone (0.3–) 0.4–0.5 (–0.6) mm long, ca. 0.5–0.6 mm thick at base, 0.4 mm distally; beak thin, 8.5–9.5 mm long, pappus white, ca. 6 mm long. – Agamospermous. – Fig. 4C , 23 , 24 .

Diagnostic notes:—This peculiar species is one of the few members of T. sect. Borealia with invariably undivided leaves. It usually has broadly winged petioles, and its relatively narrow, indistinctly bordered outer phyllaries with enormously long horns (3–5 mm), relatively thick achenes with ± subsparse short spinulosity and a gradual transition into a thick, short, broadly conical cone, are the main diagnostic features. Its closest neighbour, T. calens , has outer phyllaries of a broader shape, most of the middle leaves pinnatilobed to pinnatipartite, with blotched interlobes, and a much longer beak of the achenes.

Distribution:—Because of the very distinctive appearance, it was possible to identify this species not only from the Central Altai (Ulaganskiy Pereval) but also from the Kosh-Agach District of the East Altai, and from the adjacent Tuva Republic.

Specimens examined:—[ RUSSIA, Altai Republic] Usť-Ulagan District, range of Aigulakskii Khrebet, meadows in the vicinity of Myortvye Ozera ( Lakes ) near the Ulaganskiy Pereval pass, 1850–1900 m, 2 Jul 1988, J. Kirschner , cultivated as T 151 ( PRA, no. det. 36746). – Ibidem , cultivated as T 152 ( PRA, no. det. 36744). – Altai, Kosh-Agach District , the Chikhachov Range , upper Karagai R., ca. 50.02° N, 89.24° E, ca. 2245 m, 6 Aug 2002, I. Artemov 35 ( NS 7133 , photo!). – Altai Republic, Severo-Chuiskiy Range, ca. 12 km SW of Aktash, E of Eshtykol Brook , 2400–2500 m, 50°13.7’N, 87°29’E, 9 Aug. 2003, A. Chlebicki, cult. as JŠ 7863 ( PRA, no. det. 37794). – Ibidem, cult. as JŠ 7864 ( PRA, no. det. 37796). – Tuva, Ulug-Khemskiy District , the West Sayan , Uyuk Range, upper Oorosh-Oimak River , Mt. Vetrov , 2100 m, 13 Jul 1975, M. Lomonosova & V. Rogulin 868 ( NS 42151 , photo!). – Less certain identification:— Altai, Kosh-Agach District , Ukok Plateau, valley of upper Kalguta River , 2410 m, 49.18° N, 88.03° E, 25 Jul 2002, I. Artemov 158/24 ( NS 7134 , photo!) .

Figures

FIGURE 4. Details of involucres of Taraxacum species from the Altai, in alphabetic order. A, T. peracre (PRA, T 55); B, T. perdecorum (PRA, no. det. 35992); C, T. peschkovae (PRA, no. det. 35855); D, T. seminudum (PRA, JŠ 2597); E, T. tortisquameum (PRA, no. det. 35983); F, T. xanthellum (PRA, T 173); G, T. xiphodon (PRA, T 162). Scale bars: D = 2 mm; A–C, E–G = 5 mm.

FIGURE 23. Taraxacum peschkovae. The holotype. Photo M. Hladík.

FIGURE 24. Taraxacum peschkovae. A, general habit (PRA, no. det. 35855, holotype); B, achenes (PRA, from specimens cultivated as T 151); C, achenes (PRA, no. det. 37796).