Cerastium arcticum

Lange in G. C. Oeder et al.

in G. C. Oeder et al., Fl. Dan. 17(50): 7, plate 2863. 1880.

Common names: Arctic mouse-ear chickweed céraiste arctique
Synonyms: Cerastium alpinum var. procerum Lange Cerastium alpinum var. uniflorum Durand Cerastium arcticum subsp. hyperboreum (Tolmatchew) Böcher Cerastium arcticum subsp. procerum (Lange) Böcher Cerastium arcticum var. procerum (Lange) Hultén Cerastium arcticum var. vestitum Hultén Cerastium hyperboreum Cerastium nigrescens subsp. arcticum (Lange) P. S. Lusby
Treatment appears in FNA Volume 5. Mentioned on page 77, 78, 79, 82.

Plants perennial, loosely mat-forming but not pulvinate, rhizomatous. Stems erect, from decumbent base, 5–30 cm, sparsely to densely pubescent, hairs spreading, straight, often glandular; small axillary tufts of leaves usually absent. Leaves subsessile; blade broadly elliptic to obovate or rotund, larger blades in midstem region, 5–22 × 2–8 mm, apex round and obtuse, rarely broadly acute, pubescence ciliate and strigose, hairs long and eglandular, mixed with shorter eglandular hairs, colorless to somewhat fuscous; proximal leaves not strongly marcescent, blade oblanceolate, often broadly so, spatulate. Inflorescences 1–3-flowered, lax cymes, with patent, multicellular, long, glandular-hairs; proximal bracts broadly lanceolate, pubescence as leaves; distal bracts narrowly lanceolate, margins narrow, scarious, glandular-pubescent. Pedicels ± straight or somewhat curved at apex, 5–45 mm, 1–4 times as long as sepals (rarely longer), pubescence long and glandular. Flowers: sepals narrowly lanceolate, 8–11 mm, margins narrow, apex acuminate, hairs ascending, long, glandular and eglandular; petals 12–18 mm, 1–2 times as long as sepals, apex 2-fid; stamens 10; styles 5. Capsules broadly conic, straight or almost so, 14–18 mm, 1.5–2 times as long as sepals, teeth 10, ± erect, margins convolute. Seeds redbrown, 1.1–1.3 mm diam., tuberculate; tubercles acute; testa not inflated, closely enclosing seed. 2n = (54) 108.


Phenology: Flowering summer.
Habitat: Arctic tundra and solifluction areas, talus slopes, beaches, coastal grassland and seepage areas, exposed rocky headlands
Elevation: 0-400 m

Distribution

V5 161-distribution-map.gif

Greenland, Nfld. and Labr. (Labr.), N.W.T., Nunavut, Que., n Europe (Franz Joseph Land), n Europe (Novaya Zemlya), n Europe (Svalbard)

Discussion

Cerastium arcticum has been a much confused and misunderstood species, recently separated from C. nigrescens Edmonston ex H. C. Watson on seed characters. The latter has large seeds with loose, inflated testae, whereas C. arcticum has seeds that are smaller and have tight testae that cannot easily be removed (A. K. Brysting and R. Elven 2000). Much of the North American material previously placed in C. arcticum is now considered to belong to a distinct species, C. bialynickii Tolmatchew (see comments under that species). Cerastium alpinum differs from C. arcticum in having very long, flexuous, translucent hairs which often mat together. In C. arcticum and other members of the complex, the hairs are usually straight, yellowish, and not flexuous. Cerastium arcticum may on occasion have some pubescence like that of C. alpinum; such plants have been named C. arcticum var. vestitum. Whether they represent introgression of C. alpinum into C. arcticum, as suggested by E. Hultén (1956), is uncertain.

Selected References

None.

Lower Taxa

None.

"-2timesaslongassepals" is not declared as a valid unit of measurement for this property."-4timesaslongassepals" is not declared as a valid unit of measurement for this property.

... more about "Cerastium arcticum"
perigynous +  and hypogynous +
strigose +  and ciliate +
2-fid;acuminate;acute;obtuse;round +
John K. Morton +
Lange in G. C. Oeder et al. +
elliptic to broadly ovate +  and linear +
spatulate +, oblanceolate +, broadly elliptic +  and obovate or rotund +
not succulent +
often +  and herbaceous +
reduced +
herbaceous +  and scarious +
almost +  and straight +
8 +  and 6 +
1.4 cm14 mm <br />0.014 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
Arctic mouse-ear chickweed +  and céraiste arctique +
multicellular +
dish--shaped +
expanded +
Greenland +, Nfld. and Labr. (Labr.) +, N.W.T. +, Nunavut +, Que. +, n Europe (Franz Joseph Land) +, n Europe (Novaya Zemlya) +  and n Europe (Svalbard) +
0-400 m +
straight +  and curved +
central +  and peripheral +
pistillate +  and subsessile +
inconspicuous +
unisexual +  and bisexual +
stalked +  and simple +
Arctic tundra and solifluction areas, talus slopes, beaches, coastal grassland and seepage areas, exposed rocky headlands +
fuscous +  and colorless to somewhat +
straight +
ascending +  and spreading +
disc--shaped +  and dish +
0.5 cm5 mm <br />0.005 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
connate +
translucent +  and purplish +
glandular-pubescent +
swollen +
3 +  and 5 +
crassinucellate +  and bitegmic +
campylotropous +
curved +  and straight +
reflexed;erect +
0.5 cm5 mm <br />0.005 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
perigynous +  and hypogynous +
fugacious +
1-2 times as long as sepals +
1.2 cm12 mm <br />0.012 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
Flowering summer. +
in G. C. Oeder et al., Fl. Dan. +
1.1mm;1.3mm +
tuberculate +
compressed +  and angular-obovate +
persistent +
distinct +
lanceolate +
0.8 cm8 mm <br />0.008 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
branched +  and simple +
5 cm50 mm <br />0.05 m <br /> (30 cm300 mm <br />0.3 m <br />) +
subterminal +
[30 +  and 5 +
roughened +  and papillate +
distinct +
clavate +  and filiform +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Cerastium alpinum var. procerum +, Cerastium alpinum var. uniflorum +, Cerastium arcticum subsp. hyperboreum +, Cerastium arcticum subsp. procerum +, Cerastium arcticum var. procerum +, Cerastium arcticum var. vestitum +, Cerastium hyperboreum +  and Cerastium nigrescens subsp. arcticum +
rooting +  and rhizomatous +
Cerastium arcticum +
Cerastium +
species +
not inflated +
divided +
10 +  and 8 +
plant +  and mat-forming +
pubescence of simple hairs or stalked glands +  and glabrous +
not pulvinate +
19 +, 18 +, 17 +, 15] +, 13 +  and [9 +