Taraxacum hyparcticum

Dahlstedt

Ark. Bot. 4(8): 17, fig. 3. 1905.

Common names: High-Arctic dandelion
Treatment appears in FNA Volume 19. Treatment on page 249. Mentioned on page 242, 244, 250.
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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 lanceovate, 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].


Phenology: Flowering summer.
Habitat: 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
Elevation: 20–1010 m

Distribution

V19-327-distribution-map.gif

Greenland, N.W.T., Nunavut, Alaska, Eurasia

Discussion

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.

Selected References

None.

Lower Taxa

None.

"broad" is not a number."fine" is not a number.

... more about "Taraxacum hyparcticum"
shallow +
hornless;long-acuminate;horned;abruptly acuminate;caudate +
ovate +  and lanceolate +
paniculiform +  and corymbiform +
indeterminate +  and determinate +
Luc Brouillet +
Dahlstedt +
attenuate +
slender +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
compound +  and simple +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
2 cm20 mm <br />0.02 m <br /> (12 cm120 mm <br />0.12 m <br />) +
oblanceolate +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.37 cm3.7 mm <br />0.0037 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
tuberculate +, rugose +, muricate +  and smooth +
obovoid;oblanceoloid +
0.3 cm3 mm <br />0.003 m <br /> (0.37 cm3.7 mm <br />0.0037 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
broadly ovate;lanceolate +
0.34 cm3.4 mm <br />0.0034 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
filiform +
white +  and cream-colored or yellowish +
High-Arctic dandelion +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
zygomorphic +, actinomorphic +  and (3-)5-merous +
pinkish-striped +, cream-colored +  and white or pink-tinged +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
grayish +, straw-colored +  and brown +
tapered +, beaked +, flattened +, obcompressed +, compressed +, prismatic +, fusiform +, ellipsoid +, columnar +  and clavate +
Greenland +, N.W.T. +, Nunavut +, Alaska +  and Eurasia +
20–1010 m +
muricate +  and tuberculate +
winged +  and beaked +
dispersed +
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 +
indeterminate +
each +  and sessile +
green +, dark green +  and bluish black or dark purplish +
0.8 cm8 mm <br />0.008 m <br /> (4 cm40 mm <br />0.04 m <br />) +
campanulate +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
sessile +  and petiolate +
erect +  and patent +
0 (?) +  and 10 (?) +
straight +
triangular +  and deltate +
subentire +, denticulate +  and lobed +
2-carpellate +
0.55 cm5.5 mm <br />0.0055 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
sordid +  and whitish +
persistent +
0.5 cm5 mm <br />0.005 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
Flowering summer. +
closing +  and later +
distinct +  and coherent +
8 +  and 14 +
subequal +  and unequal +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
10 +  and 13 +
exalbuminous +
1 (?) +  and 10 (?) +
pinkish +  and reddish or purplish +
ascending +  and erect +
glabrate +  and glabrous +
1 +  and 5 +
scapiform +
appendaged +  and truncate +
papillate +
Undefined tribe Lactuceae +
Taraxacum hyparcticum +
Taraxacum +
species +
rounded +
white-scarious +  and scarious +
triangular +
with branched caudices +  and taprooted +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
30 cm300 mm <br />0.3 m <br /> (400 cm4,000 mm <br />4 m <br />) +
12 cm120 mm <br />0.12 m <br /> (30 cm300 mm <br />0.3 m <br />) +