Taraxacum greuteri Štěpánek & Kirschner, 2022

Štěpánek, Jan & Kirschner, Jan, 2022, Taraxacum sect. Erythrocarpa in Europe in the Alps and eastwards: A revision of a precursor group of relicts, Phytotaxa 536 (1), pp. 7-52 : 39

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

Type:— GREECE. Graecia, Peloponnes, ad Chelmos , ca. 2100–2200 m, 1985, D. Podlech, cultivated from achenes JŠ 2466 as JŠ 3748, collected in 1990 ( PRA, no. det. 33113, holotype; isotypes: PRA, no. det. 30949 and duplicates)

Etymology:—Named after outstanding Swiss botanist Werner R. Greuter (*1938), an expert in the flora of the Mediterranean (the main author of the Med-Checklist series) and an organiser of its exploration, and a specialist in plant nomenclature and taxonomy.

Diagnosis:—Plantae minutae insignes foliis canescenti-viridibus, lobis lateralibus paucis, phyllariis exterioribus numerosis, imbricatis, ovatis vel late ovatis, conspicue pallide marginatis, a speciebus similibus ( T. pindicola , T. janchenii ) praecipue acheniis badiocinnamomeis vel castaneo-brunneis, corpore erecto-spinuloso, in pyramidem conicam 0.5–0.7 (–1.0) mm longam sensim transeunte differunt.

Plants small to very small, rarely medium-sized, never slender, usually 4–7 cm tall. Plant base with a dark brown tunic, with a dirty white to brownish indumentum among petiole bases. Leaves variously erect-patent, greyish green, not spotted (but interlobes and lower leaf segments often suffused purple), outer and middle leaves almost glabrous to very sparsely arachnoid, inner ones arachnoid, spatulate, 3–5 cm long, 0.8–1.5 cm wide, pinnatisect to pinnatipartite; terminal segment dominant, usually helmet-shaped, sometimes rounded to broadly triangular, usually 0.6–1.5 cm long, 0.5–1.5 cm wide, obtuse to obtusely acute, sometimes rounded, distal margin usually convex, rarely ± straight, entire, basal lobules subrecurved to patent, acute, proximal margin ± straight, entire; lateral segments 2–3 pairs, hamate to broadly triangular-deltoid or triangular, subrecurved to hamate-recurved, usually 4–6 (–8) mm long, 3–7 mm wide at base, obtusely acute to acute, distal margin convex, less often sigmoid, entire or with 1 (–3) ± distinct teeth, proximal margin subconcave to straight, entire or with a single short broad tooth at base; interlobes short and broad, usually 1–2 (–4) mm long, 3–4 (–5) mm wide, margins raised, entire or denticulate, surface blotched brown-purple, narrowly bordered dark brown-purple; mid-vein pale greenish or light brownish; petiole short, 0.5–1.5 (–2) cm long, winged to broadly winged (narrower in later, inner leaves), pale greenish or bordered pinkish. Scapes densely arachnoid, pale greenish, subequalling leaves. Capitulum small, 2–2.5 (–3) cm wide, flat, yellow. Involucre ca. 7–9 (–10) mm wide and truncate at base. Outer phyllaries 13–18, ± appressed, imbricate, ovate to broadly ovate, (4.5–) 5.5–7 mm long, (2.5–) 3.5–5 mm wide, with a slightly elongated broadly lingulate obtuse apex, with a conspicuous coloration, with a darker olivaceous-green middle strip 0.5–1.0 mm wide (later getting broader), distally darker, with a gradual transition into a very pale greenish border to 1 mm wide, including a membranous margin 0.2–0.3 mm wide, apex ± flat to subcarinate, margin initially densely long ciliate, later glabrescent; inner phyllaries 10–11 mm long, their width ± invariable. Outer ligules flat, broad, striped grey-purple (the strip bordered red) outside, apical teeth black-purple to black, inner ligule teeth red to purple. Pollen present, pollen grains irregular (variable) in size. Stigmas long, light yellow to faintly greenish yellow, with a hyaline pubescence outside. Achenes medium dark cinnamon-brown to light castaneous-brown, 4.0– 5.5 mm long, 0.9–1.4 mm wide, body with short subdense erect to almost appressed squamules and spinules in upper 1/4–1/3, otherwise tuberculate to smooth, body gradually narrowing into a broad conical cone 0.5–0.7 (–1.0) mm long; beak (7–) 8–9.5 mm long; pappus 4–6.5 mm long, dirty white.—Agamosperm.

Diagnostic notes:—The dwarf general habit, greyish green leaves with 2–3 pairs of lateral segments, and outer phyllaries numerous, imbricate, ovate to broadly ovate are the conspicuous features of T. greuteri . The most important diagnostic characters are found on achenes: the achene colour varies between deep cinnamon-brown and castaneousbrown, the spinulosity consists of erect spinules and squamules, and achene body gradually narrows into a short conical cone ( Fig. 20 , 21 ).

Distribution and ecology:—Alpine and subalpine limestone rocky slopes and calcareous gravel, open grasslands on mountain slopes, usually between 1700–2300 m. Up to now, its occurrence has been recorded from Greece, from the Giona Massif in Phokis, and the vicinity of Chelmos on Peloponnes ( Fig. 2 ). Its IUCN conservation status is estimated as VU.

Specimens examined:— GREECE: Peloponnes, ad Chelmos , ca. 2100-2200 m, 1985, D. Podlech, cultivated as JŠ 2466 (PRA, no. det. 30947).—Nom. Ahaia, Ep. Kalavriton, the Chelmos Massif, 1.6 km W of the summit of Chelmos, rocky slopes, limestone, 2020 m, 38° N, 22°10‘30“ E, 3 Jun 1988, E. Willing 4973 (B, no. det. 30951).—Phokis, Giona, Proftis Ilias, summit area, ca. 2100–2300 m, limestone, 4 Jun 1982, F. Krendl (W, no. det. 30943).—Phokis, Ep. Parnassidhos, the Giona Massif, 3.8 km SSW of Kaloskopi, 1720–1780 m, 38°39‘30“ N, 22°18‘30“ E, 1 Jun 1988, E. Willing 4830 (B, no. det. 30953).

Figures

FIGURE 2. Distribution of species of T. sect. Erythrocarpa. Taraxacum pseudohoppenum (empty circles), T. janchenii (black pentagons), T. aquilinum (stars), T. pudilii (square), T. greuteri (diamonds).

FIGURE 20. Taraxacum greuteri (A) and T. dorchocarpum (B). Achenes and outer phyllaries. Scale bar = 1 mm.

FIGURE 21. Taraxacum greuteri. A, General habit (PRA, no. det. 33113, a part of the holotype). B, Achenes (PRA, no. det. 33113, holotype).