Arenaria humifusa

Wahlenberg

Fl. Lapp., 129. 1812.

Common names: Creeping sandwort sabline rampante
Treatment appears in FNA Volume 5. Treatment on page 52. Mentioned on page 53, 54.

Plants perennial, matted. Taproots filiform; rhizomes weak, slender, 0.5–15+ cm. Stems 5–40+, flowering-stems erect to ascending, green, 2–8 (–10) cm; internodes terete to angular, 1/2–4 times as long as leaves, shiny, glabrous or occasionally sparsely stipitate-glandular at distalmost internodes. Leaves connate basally, with scarious sheath 0.2–0.3 mm, sessile; blade weakly to prominently 1-veined, narrowly oblong or elliptic to ovatelanceolate, 2–12 × 1–3 mm, subsucculent, margins thickened, herbaceous, shiny, smooth, apex blunt to acute, prominently pustulate or not, glabrous; axillary leaf clusters absent. Inflorescences terminal, open, leafy, 1–3-flowered cymes or often flowers solitary. Pedicels erect in fruit, 1–10 mm, minutely retrorsely pubescent to stipitate-glandular. Flowers: sepals green, 3-veined, 2 lateral-veins 1/2–3/4 times as long as midvein, more prominent in fruit, not keeled, ovate (herbaceous portion ovate), 2.5–4 mm, not enlarging in fruit, apex obtuse or somewhat acute, not pustulate, glabrous; petals oblanceolate, 3–4 mm, ± 11/2 times as long as sepals, apex acute. Capsules tightly enclosed by calyx, broadly ellipsoid, 4–4.5 mm, ca. 11/4 times as long as sepals. Seeds 12–18, brown, reniform, compressed, 0.5–0.7 mm, shiny, faintly rugulose. 2n = 40, 44 (both Europe).


Phenology: Flowering spring–summer.
Habitat: Moist, calcareous gravels and rock crevices
Elevation: 0-100 m

Distribution

V5 102-distribution-map.gif

Greenland, St. Pierre and Miquelon, Man., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Europe

Discussion

Arenaria humifusa is similar to A. longipedunculata, but is smaller in some dimensions than that species.

Selected References

None.

Lower Taxa

None.

"/4timesaslongassepals" is not declared as a valid unit of measurement for this property."/2-4timesaslongasleaves" is not declared as a valid unit of measurement for this property."/2-3/4timesaslongasmidvein" is not declared as a valid unit of measurement for this property."/2timesaslongassepals" is not declared as a valid unit of measurement for this property.

... more about "Arenaria humifusa"
not pustulate +, not +  and pustulate +
Ronald L. Hartman +, Richard K. Rabeler +  and Frederick H. Utech +
Wahlenberg +
Laciniate (?) +, Emarginate (?) +, Jagged (?) +, 2-fid (?) +  and Entire (?) +
0.2 cm2 mm <br />0.002 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
elliptic +  and ovatelanceolate +
1mm;3mm +
smaller +
herbaceous +  and scarious +
ellipsoid +
0.4 cm4 mm <br />0.004 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Creeping sandwort +  and sabline rampante +
1-3-flowered +
dish--shaped +
expanded +
Greenland +, St. Pierre and Miquelon +, Man. +, Nfld. and Labr. +, N.W.T. +, N.S. +, Nunavut +, Ont. +, P.E.I. +, Que. +  and Europe +
0-100 m +
straight +  and curved +
central +  and peripheral +
inconspicuous +
unisexual +  and bisexual +
8 cm80 mm <br />0.08 m <br /> (10 cm100 mm <br />0.1 m <br />) +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
stalked +  and simple +
Moist, calcareous gravels and rock crevices +
disc--shaped +  and dish +
leafy +  and open +
stipitate-glandular +  and glabrous +
terete +  and angular +
ovate +  and not keeled +
not enlarging +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
connate +
swollen +
3 +  and 5 +
crassinucellate +  and bitegmic +
campylotropous +
minutely retrorsely pubescent +  and stipitate-glandular +
0.1 cm1 mm <br />0.001 m <br /> (1 cm10 mm <br />0.01 m <br />) +
fugacious +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Flowering spring–summer. +
0.5 cm5 mm <br />0.005 m <br /> (15 cm150 mm <br />0.15 m <br />) +
rugulose +
compressed +  and reniform +
persistent +
connate +  and distinct +
lanceolate;broadly ovate +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
grooved +, branched +  and simple +
prostrate;ascending or erect +
terete;ellipsoid +
[30 +  and 3 +
papillate +
distinct +
filiform +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Spergulastrum +
Arenaria humifusa +
Arenaria +
species +
ascending;recurved +
divided +
10 +  and 8 +
rhizomatous +  and taprooted +
plant +  and matted +
pubescence of simple hairs or stalked glands +  and glabrous +
11 +, 10 +, 8 +  and [7 +