Taraxacum stepanovae Woroschilov (1972: 37)

Kirschner, Jan, Štěpánek, Jan & Buryy, Vladimir V., 2025, Towards a revision of Taraxacum sect. Borealia (Compositae, Crepidinae) in Siberia and the continental Far East, with special reference to the dandelions of the Altai and Kamchatka, Phytotaxa 679 (1), pp. 1-147 : 33-34

8. Taraxacum stepanovae Woroschilov (1972: 37)

Type:—[ RUSSIA] Kamchatka, Olyutorskiy raion, Apuka, s. Zaozernoe , ... u morya [Olyutorskiy District, village of Apuka, settlement of Zaozernoe, by the sea], 20 May 1965, G. A. Belaya & K. D. Stepanova ( MHA, holotype, photo!) .

Etymology:—Named after an important botanist of Kamchatka, K. D. Stepanova (К. Д. Степанова), having dealt with the meadow vegetation since the 1960’s.

Plants delicate, relatively small, to ca. 12 cm tall. Petiole unwinged or very narrowly winged, usually suffused pink or purplish, tunic slightly developed. Leaves ± mid-green, usually with ± purplish mid-vein, glabrous, linear-oblong in outline, 0.6–2 × 6–10 cm, pinnatisect; terminal segment distinct, usually narrowly triangular-sagittate, sometimes ± narrowly triangular to tripartite, basal lobules usually recurved, sometimes ± patent, margins entire; lateral segments in 3–4 pairs, conspicuously recurved, in some leaves subpatent, usually linear-triangular to narrowly triangular, acuminate, most often entire, mid-vein usually pink or purplish; interlobes narrow, entire or with a single tooth or lobule. Scapes brownish green, often suffused pink, only sparsely arachnoid below capitulum, overtopping leaves. Capitulum white, ca. 3 cm wide. Involucre light green to dark olivaceous-green, 7–8 mm wide and rounded at base. Outer phyllaries usually 9–12, appressed, subimbricate, usually broadly ovate, inner of them to lanceolate, usually 4–6 × 2–3 mm, usually with a blackish or black-green middle strip (usually to ca. 1 mm wide, sometimes to 1.8 mm wide), strip sometimes ± missing, with a gradual transition into a broad whitish-green zone, border whitish membranous, ca. 0.3 mm wide, apex with a black, relatively thin horn ca. 1.0– 1.5 mm long (the earliest capitula with phyllaries almost flat); rarely whole phyllary pale greenish, including horns; inner phyllaries ca. 11–12 mm long, usually ± linear, sometimes all pairs coalescing, then phyllaries broad, not numerous, apex corniculate. Outer ligules white, striped pink or grey-pink outside, teeth grey-purplish, inner ligule teeth ± dirty pinkish. Stigmas dark discoloured. Pollen present, pollen grains irregular in size. Achenes ochraceous-reddish when immature, mature ones deep red-brown, ca. 4.5–4.8 × 1.0– 1.1 mm, body ± densely shortly spinulose and tuberculate in upper 1/3–1/5, ± gradually narrowing into a subconical cone 0.8–1.0 mm long, ca. 0.5 mm thick at base, ca. 0.4 mm distally; beak thin, 6–8 mm long, pappus white, ca. 6.5 mm long. – Agamospermous. – Fig. 16 .

Diagnostic notes:— Taraxacum stepanovae possesses a series of unusual, distinctive features, such as white flowers, red-brown achenes or broadly ovate, conspicuously and broadly bordered outer phyllaries with black horns. It is not close to any member of T. sect. Borealia known from Kamchatka, with the exception of T. albescens which is distinct in the patent, usually deltoid leaf lateral segments, and in its less conspicuous, narrower whitish border.

Distribution:—This very distinctive species is known from the northernmost Kamchatka, from two neighbouring districts, Olyutorskiy District and Karaginskiy District (it grows on Karaginskiy Island in the latter district).

Specimens examined (each specimen studied on multiple detailed photographs):— [ RUSSIA] Kamchatka, Olyutorskiy District, southern foot of Mt. Ledyanaya , 12 Jul 1976, N . Gorshkov & A . Kozhevnikov ( LE, VLA). – Kamchatka, Karaginskiy District, Karaginskiy Island, Mt. Pereval , 22 Aug 1976, N . Gorshkov & A . Kozhevnikov ( LE). – Kamchatka, Olyutorskiy District , village of Apuka, settlement of Zaozernoe, by the sea], 13 May 1965, G. A . Belaya & K . D. Stepanova ( VLA). – Kamchatka, Olyutorskiy District, Vatyna Pass , Snegovoi Ridge, 700 m a.s.l., 12 Jul 1976, V . Barkalov & A . Smirnov ( VLA). – Olyutorskiy District, SW. of Mt. Mogolai (1632 m), valley of upper Apukvayam River , 8 Jul 1976, V . Barkalov & A . Smirnov ( VLA) .

Figures

FIGURE 16. Taraxacum stepanovae. A plant of the holotype herbarium sheet (MHA).