Taraxacum subcollinum Kirschner & Stepanek 2023, sp. nov.
Creators: name: Kirschner, Jan
name: Štěpánek, Jan
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Asterales
Asteraceae
Taraxacum
Taraxacum subcollinum

description: 13. Taraxacum subcollinum Kirschner & Štěpánek, sp. nov.   
 Type:—[RUSSIA, Irkutskaya oblast] Sibiria merid., urbs Bratsk, ad ripam sinistram lacus structilis “Bratskoe More”, ca. 10 km situ a vallo, ad marg. partis centralis urbis Bratsk, haud procul a deversorio “Bratsk”, 27–28 Oct 1985, J. Kirschner & J. Štěpánek, cultivated as JŠ 2700 (PRA, no. det. 35967, holotype; isotype: PRA, no. det. 36683).   
 Etymology:—Similar to T. collinum.   
 Exsiccates:— Taraxaca Exs., no. 1372–1375.   
  Diagnosis:—Species notabilis phyllariis involucralibus exterioribus numero 11–13, adpressis, aequabiliter saturate vel obscure olivaceoviridibus, margine inconspicue anguste membranaceis, stigmatibus luteis vel sordide luteis, acheniis pallide griseo-brunneis, 4.2– 4.9 mm longis corpore angusto, superne spinulis et squamulis tricuspidatis conspicuis tecto, in pyramidem anguste cylindricam 1.1–1.3 mm longam sensim transeunte.    
Plants small, rarely to medium-sized, usually to 10–12 cm tall. Petiole green or purplish, sparsely arachnoid, narrowly winged to winged in at least some leaves, unwinged in the other ones; plant base with yellowish hairs, tunic ± developed. Leaves deep green to mid-green, not spotted, sparsely arachnoid to subglabrous, narrowly oblong-oblanceolate in outline, usually 7–11 × 1.8–3.0 cm, most leaves pinnatisect, but usually some pinnatilobed or undivided, sinuate dentate, with 3–5 pairs of patent, narrowly triangular to linear-triangular lateral segments, distal margin most often concave and entire, sometimes with a basal shallow incision or a tooth, proximal margin straight to subconvex, entire or with one or a few minute teeth; terminal segment ± triangular to tripartite, with basal lobules ± patent, margins usually entire; interlobes variable, narrow in pinnatisect leaves, usually 5–7 × 2–3 mm, to 6–8 mm wide in pinnatilobed leaves, usually with 1–4 little teeth or short lobules, sometimes entire; mid-vein often suffused bronze. Scapes brownish green, arachnoid, equalling, sometimes overtopping leaves. Capitulum yellow, usually 3–3.5 cm wide. Involucre deep olivaceous-green or dark green, usually 8–9 mm wide and broadly rounded at base. Outer phyllaries usually 11–13, appressed, not imbricate, ovate to ovate-lanceolate, usually 5–6.5 × 2.5–3.6 mm, evenly deep olivaceous-green, often with lighter green basal part and darker apical one, sometimes with a visible thin blackish middle line, border indistinct, membranous or greenish membranous, 0.1–0.4 mm wide, margin ciliate to subglabrous, apex flat to minutely dark corniculate; inner phyllaries 13–15 mm, elongating to reach 20 mm after anthesis, ± flat. Outer ligules flat, striped greyish or pinkish grey, inner ligule teeth grey to grey-purple. Stigmas yellow to dirty yellow. Pollen present, pollen grains irregular in size. Achenes light grey, long and slender, (4.2–) 4.5–4.7 (–4.9) × 0.7–0.9 mm, body covered with long acuminate suberect spinules and tricuspidate squamules in upper 1/4, gradually narrowing into a thin cylindrical cone 1.1–1.3 × 0.2 mm; beak (8–) 9–10 mm, pappus yellowish white, 5–6 mm long. – Agamosperm. – Fig. 15.  
 Diagnostic notes:—The long, slender achenes with long suberect spinules and a long, thin, cylindrical cone are unique in T. sect. Dissecta, and could be only compared with those of T. pubescens. Outer phyllaries are ± borderless, and there is a frequent heterophylly.   
 Distribution and habitat:— Taraxacum subcollinum is known from a series of gatherings sampled along the western shore of the Bratsk reservoir, on gravelly and sandy sites, at about 400 m a.s.l.   
 Specimens examined:—[RUSSIA, Irkutskaya oblast] S. Siberia, town of Bratsk, west shore of the “Bratskoe More” reservoir, about 10 km from the dam, margin of town centre, not far from the “Bratsk” hotel, 27–28 Oct 1985, J. Kirschner & J. Štěpánek, cultivated as JŠ 2700 (PRA, no. det. 36683, with duplicates). – S. Siberia, town of Bratsk, west shore of the “Bratskoe More” reservoir, about 10 km from the dam, not far from the “Bratsk” hotel, 27–28 Oct 1985, J. Kirschner & J. Štěpánek, cultivated as JŠ 2579 (PRA, no. det. 36685). – Ibidem, cultivated as JŠ 2699 (PRA, no. det. 36690). – Ibidem, cultivated as JŠ 2701 (PRA, no. det. 36692). – Ibidem, cultivated as JŠ 2581 (PRA, no. det. 36689). – Ibidem, cultivated as JŠ 2580 (PRA, no. det. 36687).
description: Published as part of Kirschner, Jan & Štěpánek, Jan, 2023, A taxonomic revision of Taraxacum sect. Dissecta, a continental steppe group common in Siberia and adjacent regions of Central Asia, pp. 1921-1935 in Phytotaxa 590 (1) on pages 1921-1935, DOI: 10.11646/phytotaxa.590.1.1, http://zenodo.org/record/7780271