Taraxacum pyrenaicum subsp. balcanicum Štěpánek & Kirschner, 2022

Štěpánek, Jan & Kirschner, Jan, 2022, A hotspot of endemism: Oreophytic Taraxacum species (Compositae, Crepidinae) in the mountains of Bulgaria, Phytotaxa 569 (1), pp. 1-139 : 19-20

a. Taraxacum pyrenaicum subsp. balcanicum Štěpánek & Kirschner , subsp. nov.

Type:— Bulgaria, montes Pirin , opp. Bansko , vallis glacialis Popovoezeren cirkus: locis scaturiginosis supra (situ boreo-occid.) lacum parvum lacuus Banski ezera in decl. ± orientali sub saltu Samodivska porta (2500 m) inter montes Samodivski vrch (2730 m) et Malak Poležan (2822 m), ca. 5 km situ merid.-orient. a casa alpina Demjanica (1895 m), ca. 2250 m, 41° 42–43’ N, 23° 30–31’ E., 8 Aug 1997, J. Štěpánek, cultivated as JŠ 6292, collected in 1999 ( PRA, no. det. 36122, holotype; isotypes: PRA, no. det. 35837, and duplicates) .

Diagnosis:—Plantae sexuales, mediocres, basi glaberrimae, a speciebus ceteris montanis bulgaricis foliis erecto-patentibus, modice pallide viridibus, subglabris, petiolis alatis pallidis, lobis lateralibus numerosis, saepissime falcato-recurvis, involucris angustis, subobconicis, phyllariis exterioribus adpressis vel laxe adpressis, ovatis vel lanceolatis, inaequalibus, subviridibus usque saturate olivaceo-viridibus, marginibus angustissimis indistincte pallidioribus, ciliatis, acheniis pallide stramineo-brunneis cinerascentibus, corpore superne breviter spinuloso-squamulosa, pyramide basi conica, ceterum subcylindrica, bene dignoscendae.

Plants small to medium-sized, of ± compact growth, 10–15 cm tall. Plant base without tunic, glabrous among petiole bases. Leaf rosettes rich, leaves erect-patent to prostrate, light green, not spotted, almost glabrous, usually 5–11 × 1.7–2.5 cm; petiole light green, ± broadly winged to winged, 1–2 cm long; blade ± narrowly oblanceolate in outline, pinnatisect, in inner leaves distally to pinnatipartite; terminal segment broadly triangular to ± helmet-shaped, 1–2 cm long, obtusely acute, sometimes mucronate, distal margin convex or straight, entire or with an incision, basal lobules ± hamate-recurved, ± acute, proximal margin usually concave, entire; lateral segments in 4–7 pairs, often falcate-recurved, sometimes bird-wing-like, i.e. abruptly narrowed from a broad base into a longer, narrow distal part, sometimes deltoid-triangular, usually 7–12 × 4–10 mm, acute to obtusely acute, distal margin convex or sigmoid, usually entire, sometimes with a single distinct tooth, proximal margin ± straight, ± entire; interlobes short, usually 2–5 × 4–7 mm, surface without darker coloration, margin often raised, entire or with 1–2 long teeth, margin sometimes inconspicuously suffused brown-purple; mid-vein pale greenish. Scapes glabrous, pale green, later getting purplish, usually overtopping leaves. Capitulum yellow, small, ca. 2.5 cm wide. Involucre ± subobconical and 5–8 mm wide at base, green or slightly pruinose. Outer phyllaries 15–19, short, reaching only 1/3–1/2 of the inner ones, ovate to lanceolate, ± unequal, usually 4–6 × 2–3.5 mm, appressed to loosely so, light green to medium dark olivaceousgreen, sometomes slightly darker marginally and distally (distally often purplish), with a gradual transition in an indistinct, dirty membranous border 0.1–0.2 mm wide, margin shortly, densely ciliate, apex ± flat; inner phyllaries 11–12 mm long, not variable in their width. Outer ligules flat, striped dark grey-olivaceous outside, apical teeth black, inner ligules canaliculate, with apical teeth black-green. Stigmas very pale discoloured, pale yellowish with a slightly greyish-greenish hue, with hyaline, rarely apically blackish minute hairs outside. Pollen present, very regular in size. Achenes light greyish stramineous-brown, 3.7–3.9 × 1.1–1.2 mm, body, in upper 1/3–1/5, with indistinct lateral ridges, with ± dense, short spinules, sometimes ± coalescing in comb-like squamules to 0.1–0.2 mm long, body ± abruptly narrowing into a short, basally conical, otherwise subcylindrical cone 0.7–0.8 mm long; beak 6–7 mm, pappus 5–5.5 mm. – Sexual. – Fig. 1, 2D, 3.

Distribution and habitat:—Known from a single macrolocality but probably more frequent in the Pirin, southern Bulgaria. It grows in wet alpine grasslands, on acid, siliceous substrate, at the elevation around 2200–2300 m. Its IUCN conservation status is estimated as vulnerable (VU).

Diagnostic notes:—This remarkable, sexually reproducing taxon is conspicuous in having light green leaves with numerous lateral segments, and pale, winged petioles; the short outer phyllaries (sectional character) are ± loosely appressed, usually light olivaceous-green.Achenes are short, ± densely minutely spinulose above, ± abruptly narrowed in a short subcylindrical cone. The type subspecies, T. p. subsp. pyrenaicum , also a sexual taxon, has more compact leaf rosettes, leaves with more numerous and narrower lateral segments, outer phyllaries with apex bent towards involucre and often ± corniculate, achenes with sparse spinulosity and a shorter cone.

Specimens examined:— A less certain identification: Pirin , slopes of Mt. Vichren , scree, ca. 1850 m, 41° 45’ 59” N, 23° 25’ 29” E, 18 Jul 2002, J. Suda , cultivated as JK 4918 (PRA, no. det. 35905) .