Taraxacum rhodocarpum Dahlstedt (1907: 21)

Taraxacum rhodocarpum Dahlstedt (1907: 21) View in CoL

Type indication:— Hab. in Helvetia ad Zermatt ( Canton Wallis) in Gornergrat loco lapidoso humidiusculo in reg. alp. inf., ubi anno 1893 plantam fructiferam inveni.—Vallesia, Monte Bellalp ( D. Lagger s. n. T. glaucescens, Herb. Mus. Stockholm )

Type:—[ SWITZERLAND, Wallis] Stockh.: Bergianska trädgården, odl. av fr. från Schw.: Zermatt [collected by H. Dahlstedt near Zermatt in 1893, cultivated from achenes in Bergian Botanical Garden, Stockholm], 9 Jun 1904, H. Dahlstedt (S, no. det. 23198, lectotype, designated here)

Residual syntypes:— Ibidem, Jun 1899 & 9 Jun 1904, H. Dahlstedt (S, no. det. 23199); 20 Jun 1900, H. Dahlstedt (S, no. det. 23200, 23201); 29 May 1902, (S, no. det. 23202).

Exsiccate:—Taraxaca Exs., no. 756, as T. schroeterianum .

Illustrations:— Dahlstedt (1907, Plate II, fig. 40–43); herbarium images on JSTOR Global Plants pages (https://plants.jstor.org/).

Description:—Plants usually medium-sized, often subrobust, most often up to 17 cm tall. Leaves deep to dark midgreen, glabrous, rarely (in inner leaves proximally) with a few hairs on mid-vein‘s adaxial surface, usually 8–15 × 3.5–5 cm, young leaves often undivided or with 2–3 subrecurved lateral lobes and ± entire margins, middle leaves usually with 3–5 pairs of acute, narrowly triangular to ± triangular, subrecurved to subpatent lateral segments, distal margin most often sigmoid, usually with a single sub-basal tooth, or with a few little teeth, proximal margin concave, usually entire, often raised; terminal segment triangular or elongated-triangular, entire or with a single shallow incision, basal lobules narrow, acute; petiole glabrous, dark purple, narrow, unwinged; interlobes narrow, or up to 7 mm wide, entire or with 1–2 thin teeth, margin often raised; mid-vein usually purplish. Scapes glabrous, usually purplish, ± equalling or slightly overtopping leaves. Capitulum deep yellow, (2.5–) 3–3.5 cm wide. Involucre dark (blackish) olivaceous-green, rounded and 8–9 mm wide at base. Outer phyllaries (12) 13–15 (16), appressed, subimbricate or not so, lanceolate, narrowly lanceolate, sometimes ovate-lanceolate, usually 6–8 (–9) × 2–2.5 mm, surface blackgreen, border sometimes not visible, sometimes paler, up to 0.5 mm wide, margin ciliate, apex flat; inner phyllaries usually 12–13 mmlong, flat. Outer ligules flat to subcanaliculate, striped deep grey-green outside, often with purplish hue, ligule teeth blackish green. Pollen sometimes absent, usually present, pollen grains irregular in size. Stigmas discoloured, light greyish-greenish. Achenes castaneous-brown or medium dark mid-brown, 4.2–4.8 × 1.1–1.4 mm, body ± densely or subdensely covered with ± robust straight spinules and squamules up to 0.35 mm long in upper 1/4–1/3, subabruptly to subgradually narrowing in a relatively robust subcylindrical cone ca. 0.6–0.9 × ca. 0.4–0.5 mm, beak thin, 6–7 mm long, pappus ± yellowish white, ca. 5.5 mm long.—Agamosperm. 2n=32 (A. Krahulcová 1993: 292; Gustafsson 1932: 48, both under the name of T. schroeterianum ).

Taraxacum rhodocarpum , known to occur in the Western Alps of France and Switzerland, is markedly close morphologically to the group of taxa around T. reophilum van Soest (1959: 132) . They are very similar in outer phyllary characters and the robust achenes with a thick subcylindrical cone. Taraxacum reophilum , however, is the type of T. sect. Alpestria, and these two species therefore belong to the same section. The inevitable conclusion is that the name T. sect. Alpestria is a younger synonym of T. sect. Rhodocarpa.