Portulaca pilosa

Linnaeus

Sp. Pl. 1: 445. 1753.

WeedyIllustrated
Synonyms: Portulaca mundula I. M. Johnston
Treatment appears in FNA Volume 4. Treatment on page 499. Mentioned on page 496, 497, 498, 500, 501.

Plants annual; roots fibrous to slightly fleshy. Stems prostrate, suberect to erect, succulent; trichomes conspicuous at nodes and in inflorescence; branches 3–25 cm. Leaf-blades linear to oblong-lanceolate, terete to hemispheric, 5–20 × 1–3 mm, apex acute; involucrelike leaves 6–9. Flowers 5–12 mm diam.; petals dark-pink to purple, obovate, 3–5 (–7) × 1.5–3 mm; stamens 5–12 (–37); stigmas 3–5 (–6). Capsules ovoid, 1.5–4.3 mm diam. Seeds black or leaden, orbiculate (0.4–) 0.5–0.6 mm diam.; surface cells loosely arranged, short-tuberculate and stellate to rounded-stellate; tubercles long or absent. 2n = 8, 16.


Phenology: Flowering late spring–early fall, year-round in s Fla.
Habitat: Dry soils, beaches, disturbed habitats, roadsides and railroads on limestone, granitic, and sandstone outcrops
Elevation: 0-2000 m

Distribution

V4 1016-distribution-map.gif

Ala., Ariz., Ark., Fla., Ga., Kans., La., Miss., Mo., N.Mex., N.C., Okla., S.C., Tenn., Tex., Mexico, West Indies, Central America, South America

Discussion

Portulaca pilosa is a highly variable species. It exhibits morphologic variability during development, with immature plants having wider (to 4 mm), longer, and flatter leaves than mature specimens. Mature leaves are narrower, shorter, and hemispheric or terete in cross section. The Linnaean drawing of the type specimen may be an immature plant. Morphologic variability also occurs in relation to habitat differences over the large geographic range of this species. Plants growing in dry habitats have the greatest density of hairs; plants growing in moist habitats are less pilose. Plants with very dense hairs on old growth will, under more moist conditions, produce new growth with fewer hairs. Growth habit is also affected by habitat. Plants growing in warm, moist environments tend to branch quickly into a spreading habit, with erect growth following secondarily. Plants in cool, dry habitats grow erect first, then branch more slowly; the plant then has a compact habit. Specimens from Alabama, Arizona, Florida, Louisiana, Mississippi, New Mexico, and Texas exhibit all morphologic conditions. Those from Arkansas, Kansas, Missouri, and Oklahoma usually occur in shallow, sandy soils, often on rocky outcrops, and are often highly branched, compact, short, and not very pilose.

Selected References

None.

Lower Taxa

None.
... more about "Portulaca pilosa"
James F. Matthews +
Linnaeus +
occasionally dentate;crisped +
flattened +, subterete +  and terete +
3 cm30 mm <br />0.03 m <br /> (25 cm250 mm <br />0.25 m <br />) +
circumscissile +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.43 cm4.3 mm <br />0.0043 m <br />) +
membranaceous +
Ala. +, Ariz. +, Ark. +, Fla. +, Ga. +, Kans. +, La. +, Miss. +, Mo. +, N.Mex. +, N.C. +, Okla. +, S.C. +, Tenn. +, Tex. +, Mexico +, West Indies +, Central America +  and South America +
0-2000 m +
open +, subsessile +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Dry soils, beaches, disturbed habitats, roadsides and railroads on limestone, granitic, and sandstone outcrops +
open +  and congested +
paniculate +  and racemose +
0.5 cm5 mm <br />0.005 m <br /> (2 cm20 mm <br />0.02 m <br />) +
linear +  and oblong-lanceolate terete +
exstipulate +  and secund +
subopposite +  and alternate +
involucrelike +
plurilocular +
half-inferior;inferior +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
dark-pink +  and purple +
ephemeral +
distinct +
obovate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Flowering late spring–early fall, year-round in s Fla. +
fibrous +  and slightly fleshy +
variously sculptured granular;stellate-tuberculate +
leaden +  and black +
0.5mm;0.6mm +
sculptured +  and smooth +
orbiculate +
herbaceous;scarious +
Weedy +  and Illustrated +
5 +  and 12 +
suffrutescent +
suberect +  and erect +
succulent +
3 +  and 5 +
stellate +  and rounded-stellate +
Portulaca mundula +
Portulaca pilosa +
Portulaca +
species +
fleshy +  and succulent +
9 +, 8 +, 5 +  and 4 +