The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Walker's evening-primrose, Walker's sun-cup

Shockley's evening-primrose

Habit Herbs annual or short-lived perennial, villous, usually densely so proximally, less dense to glabrate distally, sometimes hairs somewhat appressed and shorter on leaves, also sometimes glandular puberulent on distal parts. Herbs annual, glandular puberulent throughout, or glabrate and glaucous distally.
Stems

slender, unbranched or branched from base, 10–60 cm.

several, 10–100 cm.

Leaves

in basal rosette and/or cauline, often purple-dotted, 2–22 × 0.4–3.5 cm;

petiole 0.4–8 cm;

blade pinnately lobed, sometimes lateral lobes greatly reduced or absent and blade reduced to terminal lobe only, terminal lobe oblong or cordate to ovate, 1–5 × 0.5–3.2 cm, margins serrate, brown oil cells prominently lining veins abaxially.

primarily in poorly defined basal rosette, cauline greatly reduced when present;

petiole 0.4–8 cm;

blade unlobed, ovate to cordate, 2–11.5 × 1.4–5 cm, margins sinuate-dentate, brown oil cells prominently lining veins abaxially.

Racemes

erect, elongating after anthesis.

erect, elongating in anthesis.

Flowers

opening at sunrise;

buds individually reflexed, with apical free tips less than 1 mm;

floral tube 0.5–1.5 mm, glabrous or sparsely villous inside;

sepals 1.5–5 mm;

petals bright yellow, fading pale orange or lavender, 1–6 mm;

stamens unequal, filaments of antisepalous stamens 1–3 mm, those of antipetalous ones 0.3–2 mm, anthers 0.5–2 mm, glabrous or sparsely ciliate;

style 1.5–6 mm, stigma surrounded by anthers at anthesis.

opening at sunrise;

buds without free tips;

floral tube 2–5 mm, villous inside;

sepals 1.5–3.5 mm;

petals lavender, paler and often with flecks toward base, often yellow at very base, fading darker lavender, 2–6 mm;

stamens unequal, filaments of antisepalous ones 1.8–3 mm, of antipetalous ones 1–2.5 mm, anthers 0.6–1 mm, glabrous or sparsely ciliate;

style 4–7 mm, stigma surrounded by anthers at anthesis.

Capsules

spreading or ascending, oblong-cylindrical, 11–45 mm;

pedicel 5–30 mm.

erect, clavate, 7–13 mm;

pedicel 2–5 mm.

Seeds

0.6–1.2 mm.

1–1.2 mm.

2n

= 14.

Chylismia walkeri

Chylismia heterochroma

Phenology Flowering May–Jun.
Habitat Alluvial and rocky slopes.
Elevation 600–2200 m. (2000–7200 ft.)
Distribution
sw United States
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 2 (2 in the flora).

P. H. Raven (1962, 1969) determined this species to be self-incompatible and primarily autogamous.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Chylismia heterochroma is known from Churchill and Lander counties, Nevada, south to Lincoln and southern Nye counties, Nevada, to adjacent California (Mono Lake, Mono County, and central Inyo counties). P. H. Raven (1962, 1969) determined this species to be self-compatible and autogamous.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaves primarily cauline, rarely forming inconspicuous basal rosette, lateral lobes usually greatly reduced or absent; petals 1–3 mm; anthers 0.5–0.8 mm.
subsp. walkeri
1. Leaves primarily basal, forming conspicuous rosette, cauline reduced or absent, lateral lobes usually well developed; petals 2.8–6 mm; anthers 1–2 mm.
subsp. tortilis
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Chylismia > sect. Chylismia Onagraceae > subfam. Onagroideae > tribe Onagreae > Chylismia > sect. Chylismia
Sibling taxa
C. arenaria, C. atwoodii, C. brevipes, C. cardiophylla, C. claviformis, C. confertiflora, C. eastwoodiae, C. exilis, C. heterochroma, C. megalantha, C. multijuga, C. munzii, C. parryi, C. scapoidea, C. specicola
C. arenaria, C. atwoodii, C. brevipes, C. cardiophylla, C. claviformis, C. confertiflora, C. eastwoodiae, C. exilis, C. megalantha, C. multijuga, C. munzii, C. parryi, C. scapoidea, C. specicola, C. walkeri
Subordinate taxa
C. walkeri subsp. tortilis, C. walkeri subsp. walkeri
Synonyms Camissonia walkeri, Oenothera walkeri Oenothera heterochromas., Camissonia heterochroma, C. heterochroma var. monoensis, O. heterochroma subsp. monoensis, O. heterochroma var. monoensis
Name authority A. Nelson: Bot. Gaz. 56: 66. (1913) — (as Chylisma) (S. Watson) Small: Bull. Torrey Bot. Club 23: 193. (1896) — (as Chylisma)
Web links