Taraxacum peracre 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 : 54-56

publication ID	https://doi.org/10.11646/phytotaxa.679.1.1
DOI	https://doi.org/10.5281/zenodo.16717081
persistent identifier	https://treatment.plazi.org/id/0399F353-FFA6-FF81-FF78-F9964CD7B8FF
treatment provided by	Felipe
scientific name	Taraxacum peracre Kirschner & Štěpánek
status	sp. nov.

Treatment

19. Taraxacum peracre Kirschner & Štěpánek View in CoL , 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 55 ( PRA, no. det. 35990, holotype) .

Etymology:—Very acute (shape of leaf segments).

Diagnosis:— Taraxaci perdecori affine sed segmentis foliorum lateralibus recurvatis, numerosis, anguste acuminatis, dentatis vel incisis, stigmatibus obscurioribus, phyllariis exterioribus ± adpressis vel erectis notabile.

Plants small to medium-sized, usually to 12–14 cm tall. Petiole purplish to brownish-purple, ± sparsely arachnoid, narrowly winged to ± unwinged, tunic absent. Leaves ± mid-green, mid-vein usually suffused brownish purple, surface often irregularly spotted or blotched, oblong-oblanceolate in outline, conspicuously pinnatisect, usually with 5–7 pairs of narrow, linear-triangular to narrowly triangular, recurved or patent, acute to acuminate lateral segments, distal margin ± straight, remotely dentate, teeth filiform, or with an incision forming elongated acuminate lobule, proximal margin ± straight, entire, some, usually the outermost leaves with patent, linear, entire segments; terminal segment most often with an elongated, narrowly triangular to lingulate terminal part and patent, acute, narrowly triangular basal lobules, terminal part sometimes constricted or with a pair of large teeth, otherwise entire; interlobes usually bordered, with several distinct teeth or thin lobules. Scapes brownish green, usually suffused reddish, ± arachnoid, ± equalling leaves. Capitulum yellow, 2.5–3.5 cm wide. Involucre olivaceous-green or dark so, ca. 9 mm wide and rounded at base. Outer phyllaries 11–13, appressed or loosely appressed to erect, later erect, not imbricate, usually narrowly lanceolate, usually (6.5–) 7.5–8.5 × (2.0–) 2.4–3.0 (–3.3) mm, surface evenly light to blackish olivaceous-green, border usually indistinct, narrow, ca. 0.1 mm wide (and bordered purplish inside), sometimes 0.3–0.4 mm wide, margin ± glabrous, apex corniculate, in later capitula with distinct horns, usually 1–1.5 mm long; inner phyllaries usually 13–14 mm long, olivaceous-green, flat to corniculate. Outer ligules ± flat, striped grey-purple outside, teeth black-purple, inner ligule teeth yellow-purplish. Stigmas light yellowish green or light greenish, with grey pubescence outside. Pollen present, pollen grains irregular in size. Achenes light greyish stramineous-brown, 3.0–3.2 (–3.5) × 0.9–1.0 mm, body ± densely and shortly spinulose and squamulose in upper 1/4, gradually narrowing into a broadly conical cone 0.5–0.6 mm long, ca. 0.5 mm thick at base, ca. 0.3 mm distally, beak ± thin, ca. 6.0– 7.5 mm long, pappus white, 6–6.5 mm long. – Agamospermous. – Fig. 4A View FIGURE 4 , 34 View FIGURE 34 , 35 View FIGURE 35 .

Diagnostic notes:—The thick, short, conical cone is a feature shared by T. perdecorum and T. peracre , and separating this species pair from the rest of the group of T. ochotense – T. perdecorum . Taraxacum peracre is distinguished by appressed to erect outer phyllaries and relatively numerous, recurved to patent, linear, linear-triangular or very narrowly triangular, acuminate leaf lateral segments. This leaf shape is unique in T. sect. Borealia in the whole of Asiatic Russia.

Distribution:—Although not so common as T. perdecorum , T. peracre is relatively widely distributed in the Altai, mainly in the mountains of the central Altai. It was repeatedly collected at various sites near the Ulaganskiy Pereval and around Mt. Aktash in the Kurai Range.

Specimens examined:—[ RUSSIA, Altai Republic] Usť-Ulagan District, range of Aigulakskii Khrebet, meadows in the vicinity of Myortvye Ozera ( Lakes ) near the pass Ulaganskiy Pereval , 1850–1900 m, 2 Jul 1988, J. Kirschner , cultivated as T 55 ( PRA, no. det. 36740). – Ibidem, cultivated as T 46 ( PRA, no. det. 36738). – Ibidem, cultivated as T 47 ( PRA, no. det. 36737). – Ibidem, cultivated as T 48 ( PRA, no. det. 36735). – Ibidem, cultivated as T 49 ( PRA, no. det. 36733). – Ibidem, cultivated as T 56 ( PRA, no. det. 36731). – The Altai Mts., Usť-Ulagan District , the Kurai Range [Kuraiskiy Khrebet], slopes of Mt. Aktash , 2600 m, 3 Jul 1988, J. Kirschner, cultivated as T 214 ( PRA, no. det. 36736). – Ibidem, cultivated as JŠ 3377 ( PRA, no. det. 36734). – Gorno-Altaisk, Shebalino District , along the river Sema in the vicinity of Cherga, 24–25 Jun 1988, J. Kirschner, cultivated as JŠ 3317 ( PRA, no. det. 35797) .