Taraxacum chamarense Peschkova (1977: 227)

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 : 133-134

57. Taraxacum chamarense Peschkova (1977: 227)

Type:—[ RUSSIA, Buryatia] Khamar-Daban, istoki r. Mishikhi , podgol’tsovoi poyas, bereg reki, na syrom peske [Khamar-Daban Mts., sources of Mishikha River, subalpine zone, river bank on humid sand], 1380 m, 20 Aug 1963, M. Ivanova 1731 ( LE, no. det. 6133) .

Etymology:—Khamar-Daban [Хамар-Дабaн], a mountain range in the southwestern vicinity of Lake Baikal, Buryatia]

Note:—On the holotype herbarium sheet, one of the plants is marked “a” and annotated “a – Taraxacum chamarense ”. The other plant has achenes, corresponding to those in Ivanova 1988, and used for the original decription.

Plants relatively robust, rather tall due to the habitat, usually to 25 cm. Petiole narrowly winged, ± glabrous, tunic absent. Leaves (only late ones present) ± mid-green, ± glabrous, oblanceolate, ca. (5–) 10–15 (–20) × ca. 2–3 (–4.5) cm, undivided, remotely dentate to remotely sinuate-lobulate; mid-vein green or pinkish. Scapes brownish green, subglabrous, sparsely arachnoid below capitulum, overtopping leaves. Capitulum yellow, ca. 3–4 cm wide. Involucre black-green, ca. 8 mm wide and ± rounded at base. Outer phyllaries ca. 11–13, very unequal, loosely appressed, subimbricate, broadly lanceolate to narrowly ovate, usually 6.5–10 × 2.5–3.5 mm, surface black-green with black middle line, border sharply delimited, whitish to whitish-membranous, ca. 0.3–0.6 mm wide, margin ± glabrous, apex with a thick, robust black horn 1–2 mm long; inner phyllaries 14–16 mm long, black-green, with horns to ca. 1.5 mm, or corniculate. Outer ligules striped very light greyish pink or pinkish outside. Stigmas yellow-green. Pollen present, pollen grains irregular in size. Achenes cinnamon-brown to slightly reddish deep brown, ca. 4.5–4.8 × 1.2–1.4 mm, ± densely spinulose in upper 1/3, subabruptly to subgradually narrowing into a thick conical cone ca. 0.5–0.7 × 0.5–0.6 mm; beak thin, ca. 9 mm long, pappus white, ca. 6–7 mm long. – Agamospermous.

Diagnostic notes:—If we disregard a possible taxonomic heterogeneity of the three selected elements of the original material, T. chamarense may be characterized by the thick, cinnamon-brown to ± brown achenes with a thick, short, conical cone, and the blackish, unequal, clearly bordered outer phyllaries. Further material is needed to characterize this species properly. The problematic character of the original material is primarily grounded in a rather doubtful conspecificity of the flowering and fruiting specimens, and in the rather late stage of development of the holotype.

Distribution:— Taraxacum chamarense is known to occur in the vicinity of Lake Baikal, mainly in the Khamar-Daban Range.

Specimens examined:—[ RUSSIA] Buryatiya, Khamar Daban mountains, right source of river Margasan, upper boundary of Pinus sibirica light forest, on rocks near the waterfall, [51°23′ N, 103°18′ E], 18 Aug 1962, M. Ivanova 1988 ( NSK, photo!, paratype). – Khamar-Daban Mts. , sources of Mishikha River , subalpine zone, brook bank on humid sand, 1400 m, 20 Aug 1963, M. Ivanova 1658 ( NSK, photo!, an element of the original material, collected roughly at the type locality the same day as the holotype but not cited in the protologue) .

Another element of the original material, a paratype, is doubtfully conspecific with the holotype, although even that cannot be excluded: Baikal Lake, the southeastern shore area, bank of Langatuy River, 14 Jun 1963, M. Ivanova 44 (NSK, photo!). There is another specimen, doubtfully a part of the OM, collected at the same site as Ivanova 1988: Khamar Daban mountains, right source of river Margasan, upper boundary of Pinus sibirica light forest, on rocks near the waterfall, 18 Aug 1962, M. Ivanova 1992 (NSK, photo!). It lacks flower heads (broken off, and lost), however, and cannot be assigned to T. chamarense .