A hotspot of endemism: Oreophytic Taraxacum species (Compositae, Crepidinae) in the mountains of Bulgaria Author Štěpánek, Jan 0000-0003-4038-1998 Institute of Botany of the Czech Academy of Sciences, CZ- 25243 Průhonice 1, Czech Republic. & jan. stepanek @ ibot. cas. cz; https: // orcid. org / 0000 - 0003 - 4038 - 1998 jan.stepanek@ibot.cas.cz Author Kirschner, Jan 0000-0002-6303-713X Institute of Botany of the Czech Academy of Sciences, CZ- 25243 Průhonice 1, Czech Republic. & jan. kirschner @ ibot. cas. cz; https: // orcid. org / 0000 - 0002 - 6303 - 713 X jan.kirschner@ibot.cas.cz text Phytotaxa 2022 2022-10-20 569 1 1 139 http://dx.doi.org/10.11646/phytotaxa.569.1.1 journal article 172051 10.11646/phytotaxa.569.1.1 f8f7b3a8-119f-438c-95d6-5d701a007727 1179-3163 7235182 . Taraxacum chionogeiton Štěpánek & Kirschner , sp. nov. Type :— Bulgaria , Montes Rila , Maljovica [Chalet], 9 Aug 1997 , J . Kirschner , cultivated as JK 4698 ( PRA , no. det. 36149, holotype ; isotype: PRA , no. det. 35957, and duplicates) . Etymology :—Adjacent to snow-beds (from Greek χιων, snow, and γείτων, neighbour). Diagnosis :—Plantae T. saevo affines sed differunt acheniis obscure, saturate griseo-brunneis crassioribus, pyramide conica brevi, 0.5– 0.6 mm longa, foliis terrae arcte adpressis, pallide viridibus sparsissime minute maculatis et phyllariis involucralibus exterioribus arcte adpressis. Plants small, of a compact growth, to ca. 6 cm tall. Plant base without tunic, with subdense brownish hairs among petiole bases. Petiole broadly to very broadly winged, ca. 1–1.5 (–2) cm long, pale greenish or only distally adaxially pinkish in the mid-vein. Leaf rosettes tightly appressed to the ground. Leaves relatively narrow, almost glabrous (often with rarely scattered little hairs), light green, adaxially with very sparse to very sporadic little brown-purple spots, narrowly elliptical to narrowly oblanceolate or spatulate in outline, usually 3.5–5.5 × 1.0– 1.8 cm (enlarging after anthesis to reach the size up to 11 × 3 cm ), pinnatipartite to pinnatisect; terminal segment ± broadly helmetshaped to broadly triangular, obtusely acute to ± rounded, less often ± acute, usually 0.7–1.5 × 0.6–1.5 cm , distal margin convex to sigmoid, entire or with a single broad tooth or a little lobule on one or both sides, or irregularly divided in 1–3 lobules, basal lobules short, obtusely acute, ± patent to subrecurved, proximal margin subconcave to ± straight, entire; lateral segments in 3–4 pairs, patent to subrecurved, relatively short and broad, deltoid-triangular, often narrowing from a broad base in a narrow, lingulate distal part, usually 5–8 × 4–6 mm , ± acute, distal margin convex to subsigmoid, sometimes subconcave, entire, rarely with 1–2 short broad teeth, proximal margin ± straight to subconcave, entire; interlobes ± short, usually 2–3 × 2–4 mm , entire or with a single distinct tooth, not blotched nor bordered; mid-vein pale greenish or pinkish. Scapes ± equalling the leaf length, very sparsely arachnoid, later glabrescent, even just below capitulum, usually pale greenish. Capitulum small, 2–2.5 cm wide, yellow. Involucre dark olivaceous-green, not pruinose, ± rounded at base. Outer phyllaries 11–15, subimbricate, ± tightly appressed, ovate to broadly ovate, the uppermost ones to lanceolate, relatively short, reaching 2/5–1/2 of the inner ones, usually 4–6 × 2.5–3.5 mm , ± evenly dark olivaceous-green, with an abrupt transition in a paler, greyish-translucent border 0.1–0.2 mm wide, margin irregularly minutely ciliate, apex flat to slightly subcarinate; inner phyllaries ca. 10 mm long, of ± invariable width. Outer ligules flat, striped dark grey-olivaceous outside, later surface suffused purple, apical teeth black-purple, inner ligules ± canaliculate, their apical teeth dark yellow to greyish. Stigmas long, ± dark discoloured, light grey-green with black pubescence outside. Pollen present, pollen grains irregular in size. Achenes relatively dark, grey-brown, ± broadly turbinate, 3.6–4.5 × 1.1–1.3 mm , in upper 1/3–1/4, the achene body ± densely covered with very numerous, short (to 0.2 mm long) spinules often curved upwards, sometimes coalescing to form short bi- or tricuspidate squamules, body subabruptly narrowing into a broad, conical cone 0.5–0.6 mm long; beak thin, 5.5–7.5 mm long, pappus ± white, ca. 5 mm long. – Agamosperm. – Fig. 42, 50D. Diagnostic notes :—The dark, grey-brown, and thick achenes, a short conical cone, short, subimbricate, usually ovate, inconspicuously bordered outer phyllaries, together with leaves appressed to the ground, light green and very sparsely spotted, represent the diagnostic characters. It is most closely related to T. saevum but has dark achenes, dark discoloured stigmas, lower number of outer phyllaries and leaves with a much lower number of lateral segments. It might be compared with T. pseudobulgaricum sharing the achene shape and colour but the latter has loosely appressed outer phyllaries, stigmas light discoloured, leaves with the terminal segment usually flat rhombic, most often with a constriction in the middle, and beak slightly thickened, 4.5–5.5 mm long. Distribution and habitat :— Taraxacum chionogeiton probably is endemic to the Rila, Bulgaria ; it is known from a single macrolocality. It grows in open patches in subalpine and alpine grasslands, around 1900 m . Its IUCN conservation status is estimated as NT.