Taraxacum ajanense Woroschilov (1967: 7)

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 : 137-138

61. Taraxacum ajanense Woroschilov (1967: 7)

Type:—[ RUSSIA, The Far East] Regio Chabarovskensis , Ajan, in decl. herboso, 27 Jul 1965 , V. N. Woroschilov 12316 ( LE, no. det. 6139, holotype; isotype: MHA!) .

Etymology:—Ayan, a village in the Khabarovsk Region, the Far East.

Plants robust, to 48 cm tall (at fruiting stage in a taller meadow). Petiole ± winged (unwinged at the very base), suffused purplish; tunic absent. Leaves (after full flowering) dark green, narrowly oblong, 30–35 × 3.0– 3.5 cm in the type specimen, undivided, shallowly sinuate-dentate and denticulate, some with patent very broadly triangular shallow lobules; mid-vein purplish, at least proximally. Scapes elongated after flowering, to 48 cm long, light brownish green and suffused pinkish, arachnoid, overtopping leaves. Capitulum yellow, ca. 4 cm wide. Involucre dark or ± blackish olivaceous-green, rounded at base. Outer phyllaries probably 10–15, appressed, loosely appressed or erect, lanceolate to ovate-lanceolate, ca. 7–9 × 2.8–3.5 (–4.2) mm, dark olivaceous-green and often suffused purplish, with distinct venation, border not visible, apex with horns; inner phyllaries ca. 15–18 mm long, corniculate. Outer ligules ± flat, striped greenish-grey outside. Stigmas yellow-green. Pollen present, pollen grains irregular in size. Achenes light greyish stramineous-brown, ca. 4.6–4.8 × 0.9–1.0 mm, body conspicuously and densely spinulose in upper 1/4, some spinules to 0.3 mm long, body subabruptly to abruptly narrowing into a cylindrical cone 1.1–1.3 × 0.35–0.4 mm; beak thin, ca. (13–) 17–20 mm long, pappus yellowish white, ca. 7–8 mm long. – Fig. 97 , 98 .

Diagnostic notes:—The type specimen is in a rather late stage of development, and the characters of outer phyllaries cannot be recorded with certainty; in all likelihood, they are loosely appressed, ovate-lanceolate, without a paler border and with a distinct venation. Achenes with dense, thin and long spinules and an enormously long beak are diagnostic. Taraxacum ajanense may be intermediate between T. sect. Borealia and T. sect. Mongolica .

Distribution:—Known from the type collection only; it is confined to the Khabarovsk region.

Figures

FIGURE 97. Taraxacum ajanense. A, a detail of general habit of a fruting specimen (MHA, isotype); B, achenes (LE, no. det. 6139, holotype).

FIGURE 98. Taraxacum ajanense. General habit (LE, no. det. 6139, holotype).