Taraxacum holmenianum
Family: Asteraceae
Northern Dandelion
[Taraxacum pumilum Dahlst.]
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Plants 5-15(-20) cm; taproots branched. Stems 1-7+, ascending, purple, glabrous or glabrate. Leaves ca. 10+, horizontal to widely patent, rarely ± erect, (dark green); petioles winged mostly narrowly; blades oblanceolate to oblong-oblanceolate (runcinate), (1.5-)2-6(-9) × 0.3-1.3 cm, bases attenuate, margins lobed regularly, ± alternately, shallowly to deeply, lobes usually straight to slightly retrorse, sometimes slightly antrorse, deltate to triangular, acute to acuminate, apices acute to acuminate, faces glabrous. Calyculi of 10-14, appressed to slightly spreading, purplish, ovate to lance-ovate bractlets in 2 series, 3-6(-7.5) × 1.8-2.5(-3) mm, not or narrowly scarious, hyaline purplish, apices long-acuminate to short-caudate, tips scarious, erose. Involucres dark olive green, sometimes purplish, tips purplish, campanulate, 11-15(-20) mm. Phyllaries ca. 14 in 2 series, lanceolate to lance-ovate, 1-3 mm wide, margins not scarious or narrowly to widely scarious in proximal 1/2, sometimes distally, apices sometimes callous, sometimes also some small-horned, tips scarious, erose. Florets 30-50(-60); corollas dark yellow (outer with distinct, central greenish gray or pinkish stripe, tips dark), 15-20 × 1-3 mm. Cypselae yellowish or straw-colored, bodies obovoid to oblanceoloid, 3.5-4.2 mm wide, cones narrowly conic, 0.9-1.1 mm, beaks slender, 4.5-5 mm, ribs 12-16 (3-4 prominent), sharp, faces proximally tuberculate, muricate in distal 1/2; pappi white to yellowish, 5.5-6.5 mm. 2n = 16.

Flowering summer. Tundra hummocks and polygons, open slopes, on clay or gravel; 0-300+ m; Greenland; N.W.T., Nunavut.

Taraxacum holmenianum is a strictly Arctic species. It is distinguished by its deep yellow ligules.