Taraxacum hyparcticum Dahlst. (redirected from: Taraxacum arcticum)
Family: Asteraceae
[Taraxacum arcticum (Trautv.) Dahlst.]
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Plants (3-)5-12(-30) cm; taproots occasionally branched. Stems 1-5, ascending to erect, pinkish to reddish or purplish, (barely exceeding foliage), glabrous or glabrate (rarely sparsely villous and villous distally). Leaves fewer than 10, usually patent, rarely erect; petioles sometimes narrowly winged; blades oblanceolate (often ± runcinate), 2-12+ × (0.3-)0.5-1.2 cm, bases attenuate, margins lobed deeply and regularly to denticulate or subentire, lobes 5-6 pairs, straight to retrorse, triangular to deltate, teeth triangular 0-1 on lobes or 1-4 shallow pairs if subentire, acute to ± obtuse, apices obtuse to ± acute, faces glabrous. Calyculi of 10-14, spreading to appressed (thinner than phyllaries), dark green, broadly ovate or ovate to oblong bractlets in 2-3 series, 6-10 × 3.4-5 mm, margins narrowly hyaline, scarious, apices abruptly acuminate to caudate, strongly horned, tip ± scarious, erose. Involucres dark green to bluish black or dark purplish green, narrowly campanulate, 15-30 mm. Phyllaries 8-14 in 2 series, lanceolate to lance-ovate, 1.5-3.5 mm wide, margins narrowly (outer) to widely scarious in proximal 1/3 (inner), narrowly so distally, apices long-acuminate, sometimes callous, hornless (rarely very small horns), tips white-scarious, erose, rounded. Florets 25-50; corollas cream-colored to white or pink-tinged distally, outer pinkish-striped abaxially, 15-20 × 1.2-3 mm. Cypselae tan or straw-colored to brown (or reddish brown), sometimes grayish, bodies obovoid to oblanceoloid, 3-3.7(-4) mm, mostly broad, cones conic, 0.4-0.7 mm, beaks slender, 3.5-4.5 mm, ribs 10-13 (5-6 prominent), mostly broad, faces proximally tuberculate, muricate in distal 1/2; pappi whitish or sordid, 5-5.5(-7) mm. 2n = [24, 32, 40- some erroneous reports in literature under this name from Eurasia].

Flowering summer. Dry, moderately drained areas in tundra, raised sand terraces, low center polygons on old surfaces, sandy, eroded knolls, marine/lacustrine deposits, rocky streambeds, dry slopes; 20-1010 m; Greenland; N.W.T., Nunavut; Alaska; Eurasia.

Taraxacum hyparcticum is sporadic in Arctic Eurasia (coastal Russia from Russian Far East west to Novaya Zemlya); it is mainly high-arctic. It is characterized by its small stature and large heads with white to yellowish cream ligules.