Oenothera deltoides subsp. ambigua

(Munz) W. M. Klein

Aliso 5: 179. 1962.

Basionym: Oenothera deltoides var. ambigua Munz Amer. J. Bot. 18: 315. 1931
Synonyms: Anogra simplex Small O. albicaulis var. decumbens S. Watson O. deltoides var. decumbens (S. Watson) Munz O. simplex (Small) Tidestrom
Treatment appears in FNA Volume 10.

Herbs annual, strigillose, especially distally; from a taproot. Stems: central stem often thickened near base, branched from base, branches ascending to decumbent, not encircling stems in older plants, 5–25 cm. Leaves basal and cauline; blade rhombic-obovate to lanceolate, becoming oblanceolate to lanceolate distally, margins subentire, sometimes coarsely sinuate-dentate distally. Flowers: buds quadrangular in distal 1/2, with free tips 1–3 mm; sepals 20–30 mm; petals 18–35 mm. Capsules 40–70 × 1.5–5 mm. 2n = 14.


Phenology: Flowering (Mar–)Jun–Jul(–Sep).
Habitat: Sandy soil in Mojave Desert with Ambrosia, Cylindropuntia, or Larrea.
Elevation: 200–1300 m.

Discussion

Subspecies ambigua is restricted to a relatively small area of Mojave Desert in southeastern Nevada and adjacent areas in southwestern Utah and Arizona. W. M. Klein (1964) determined subsp. ambigua to be self-incompatible.

Selected References

None.

Lower Taxa

None.
0.5 cm5 mm <br />0.005 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
1.5mm +  and 5mm +
Warren L. Wagner +
(Munz) W. M. Klein +
5 cm50 mm <br />0.05 m <br /> (25 cm250 mm <br />0.25 m <br />) +
1 cm10 mm <br />0.01 m <br /> (5 cm50 mm <br />0.05 m <br />) +
pale green +  and yellow usually fading orange purple pale-yellow reddish or whitish +
pedicel-like +
Oenothera deltoides var. ambigua +
indehiscent +  and loculicidal +
sinuate-dentate +  and pinnatifid denticulate subentire or entire +
oblanceolate +  and lanceolate +
40 cm400 mm <br />0.4 m <br /> (100 cm1,000 mm <br />1 m <br />) +
ascending +  and decumbent +
few +  and several +
slender +
5 cm50 mm <br />0.05 m <br /> (25 cm250 mm <br />0.25 m <br />) +
quadrangular +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
straight +  and curved +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
tapering +, cylindrical +  and slightly 4-angled +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
12 cm120 mm <br />0.12 m <br /> (18 cm180 mm <br />0.18 m <br />) +
4 cm40 mm <br />0.04 m <br /> (12 cm120 mm <br />0.12 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (4 cm40 mm <br />0.04 m <br />) +
Ariz. +, Nev. +  and Utah. +
200–1300 m. +
pink +  and white +
exfoliating +
basifixed +  and versatile +
0.8 cm8 mm <br />0.008 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
4 cm40 mm <br />0.04 m <br /> (5 cm50 mm <br />0.05 m <br />) +
hispid +, lanate +  and glabrous +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
zygomorphic +  and actinomorphic +
unscented +
1 +  and several +
curved +  and straight +
indehiscent +  and dehiscent +
4-angled +, terete +, tapering +, cylindrical +, ellipsoid +, clavate +, ovoid ellipsoid +  and cylindrical rhombic-obovoid or globose +
Sandy soil in Mojave Desert with Ambrosia, Cylindropuntia, or Larrea. +
suffrutescent +
strigillose +
nodding +  and erect +
13 cm130 mm <br />0.13 m <br /> (26 cm260 mm <br />0.26 m <br />) +
deciduous +
cauline +  and basal +
1 cm10 mm <br />0.01 m <br /> (13 cm130 mm <br />0.13 m <br />) +
subentire +
pedicellate +  and sessile +
1 +  and 8 +
fading pink +  and deep pink +
obcordate +
1.8 cm18 mm <br />0.018 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Flowering (Mar–)Jun–Jul(–Sep). +
basal +  and cauline +
clavate +  and globose +
sculptured +  and smooth +
obovoid +
reduced +
1.3 cm13 mm <br />0.013 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
not spotted +
deciduous +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
parietal +, axile +  and placentation +
unequal +
adventitious +
aquatic +, amphibious +  and terrestrial +
in 2 unequal series +  and subequal +
2 times as many or as many as sepals +
with short , lateral branches +  and unbranched +
decumbent +  and ascending or erect +
petiolate +  and sessile +
intrapetiolar +
pubescent +  and glabrous +
3.5 cm35 mm <br />0.035 m <br /> (6 cm60 mm <br />0.06 m <br />) +
aquatic +, amphibious +  and terrestrial +
smooth +, reticulate +  and furrowed +
alveolate +
Anogra simplex +, O. albicaulis var. decumbens +, O. deltoides var. decumbens +  and O. simplex +
Oenothera deltoides subsp. ambigua +
Oenothera deltoides +
subspecies +
3(-5)-aperturate +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
woody +  and hard +
smooth +  and erose +
papillate +