Flora of North America species comparison

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

Chylismia sect. Chylismia

Chylismia exilis
Habit Herbs usually annual, sometimes perennial, rarely biennial.Leaves basal and cauline, usually with well-developed basal rosette; blade usually pinnately or bipinnately lobed, sometimes with scattered, irregular lobes, sometimes lateral lobes greatly reduced or absent, terminal lobe elliptic, narrowly to broadly ovate to oblong, lanceolate, oblanceolate, cordate, or subcordate. Herbs annual, glandular puberulent and sparsely villous.
Stems

slender, unbranched or branched, 10–20 cm.
Leaves

primarily cauline;

petiole 0.3–1.8 cm;

blade unlobed, narrowly ovate to elliptic, 0.3–2 × 0.3–1 cm, margins entire or inconspicuously denticulate, brownish oil cells lining veins abaxially.
Racemes

erect, elongating in fruit.
Flowers

usually opening at sunrise, rarely at sunset;

floral tube 0.4–9 mm;

petals usually bright yellow, rarely white or cream, usually with red dots basally, or lavender to purple with white or yellow basally, sometimes with darker flecks near base, fading yellow, orange, reddish, or lavender;

pollen shed singly.

opening at sunrise;

buds without free tips;

floral tube 0.4–0.5 mm, glabrous inside;

sepals 1–1.2 mm;

petals yellow, fading pale lavender, 1–1.5 mm;

stamens 4 (or 8), antisepalous, filaments 0.5 mm, anthers 0.5–0.7 mm, glabrous, when 8, then antipetalous ones smaller and abortive;

style 1.5 mm, stigma surrounded by anthers at anthesis.
Capsules

spreading or reflexed, clavate, 4–10 mm;

pedicel 3–9 mm.
Seeds

0.8 mm.
2n

= 14.

Chylismia sect. Chylismia

Chylismia exilis
Phenology Flowering Apr–Jun.
Habitat Calcareous sand, gypseous clay flats, juniper woodlands.
Elevation 1000–1900 m. (3300–6200 ft.)
Distribution
w United States; nw Mexico
from FNA
AZ; UT
[BONAP county map]
Discussion

Species 14 (14 in the flora).

Section Chylismia consists of 10 diploid (2n = 14) species, and two that are partly polyploid (2n = 14, 28) [C. scapoidea subsp. scapoidea and C. walkeri subsp. walkeri (only one tetraploid population)]; no chromosome counts are available for the remaining two species, C. atwoodii and C. confertiflora (P. H. Raven 1962, 1969). Species of sect. Chylismia usually occur on sandy desert slopes, flats, and washes, often in sagebrush shrubland in the northern part of its range, or on rock slides or cliffs, mainly in the Mojave and northwestern Sonoran deserts, the Great Basin, and the lower elevations of the surrounding Sierra Nevada and Rocky Mountains. The limits of this range stretch from southeastern Oregon, central and southern Idaho, and central Wyoming, south through Nevada and Utah to eastern and southeastern California, northern Baja California and northwestern Sonora, Mexico, Arizona, northwestern New Mexico, and western Colorado. Several species are rare; C. confertiflora and C. specicola are known only from the Grand Canyon in northwestern Arizona, C. megalantha only from the vicinity of the type locality in Nye County, Nevada, and C. atwoodii also only from a narrow area around its type locality in Kane County, Utah. Others are widespread, especially the very diverse C. claviformis (11 subspp.), C. scapoidea (4 subspp.), C. walkeri (2 subspp.), and C. brevipes (3 subspp.). Chylismia scapoidea is the only species in the genus to occur east of the continental divide, both in Colorado on the upper Arkansas River in Fremont and Pueblo counties, and much more widely in Wyoming. Chylismia does not occur west of the Cascade-Sierra Nevada axis. Because R. A. Levin et al. (2004) included only C. claviformis in their analysis, they did not test the monophyly of sect. Chylismia; however, this section is both geographically distinct and morphologically set apart by the characteristic pinnate leaves (modified in some species, which have retained the entire apical lobe but do not have the smaller lateral lobes). Most species have bright yellow petals with red dots proximally and ultraviolet reflectance distally; some subspecies of C. claviformis have white petals; three species (C. atwoodii, C. heterochroma, and C. megalantha) have lavender or purple petals, often with lavender or purple flecks toward base, and white or yellow at the base and no reflectance, clearly a derived condition within the section (Raven 1962, 1969).

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

Chylismia exilis, known from Kane and San Juan counties in Utah and northern Coconino and Mohave counties in Arizona, is cryptic due to its small size. It may not be as rare as assumed, since it is difficult to spot in the field. 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. Stamens usually 4, rarely 8, then antipetalous anthers abortive, smaller.
C. exilis
1. Stamens 8, anthers all fertile.
→ 2
2. Petals lavender or purple, often with purple or lavender flecks near base.
→ 3
3. Stigma surrounded by anthers at anthesis, plants autogamous; petals 2–6 mm.
C. heterochroma
3. Stigma exserted beyond anthers at anthesis, plants outcrossing; petals 7–14 mm.
→ 4
4. Capsules 8–14 mm, erect or ascending; floral tubes 4–9 mm.
C. megalantha
4. Capsules 11–25 mm, spreading to reflexed; floral tubes 0.6–1 mm.
C. atwoodii
2. Petals yellow or white, often with red dots at base.
→ 5
5. Capsules distinctly clavate.
→ 6
6. Stigma surrounded by anthers at anthesis; petals 1.5–5.5(–8) mm.
C. scapoidea
6. Stigma exserted beyond anthers at anthesis; petals 2–10 mm.
→ 7
7. Mature capsules sharply reflexed; petals bright yellow.
C. munzii
7. Mature capsules ascending, spreading, erect, or slightly reflexed; petals yellow or white.
→ 8
8. Raceme branches intricate and filiform; leaves in poorly defined basal rosette; capsules 4–10 mm.
C. parryi
8. Raceme branches not filiform; leaves primarily in well-defined basal rosette; capsules 8–40 mm.
→ 9
9. Stamens subequal; leaves usually pinnately lobed, with well-developed lateral lobes, sometimes these reduced or absent, margins dentate, sinuate-dentate, or serrate.
C. claviformis
9. Stamens unequal, differentiated into 2 sets; leaves usually unlobed, rarely pinnately lobed with reduced lateral lobes, margins entire or sparsely denticulate.
C. eastwoodiae
5. Capsules oblong-cylindrical.
→ 10
10. Stigma surrounded by anthers at anthesis; petals 1–6 mm; styles 1.5–6(–7) mm; racemes erect in bud, mature buds individually reflexed.
→ 11
11. Plants perennial, base sometimes woody; leaf blades glabrous or sparsely villous; anthers glabrous.
C. specicola
11. Plants annual or short-lived perennial, base not woody; leaf blades moderately to densely villous; anthers glabrous or sparsely ciliate.
C. walkeri
10. Stigma exserted beyond anthers at anthesis; petals 3–18 mm; styles 7–18 mm; racemes erect or nodding in bud, mature buds individually reflexed or not.
→ 12
12. Racemes erect to nodding, elongating in bud, mature buds individually reflexed; plants virgate; floral tubes 1–3 mm.
C. multijuga
12. Racemes nodding, mostly elongating after flowers open; plants not virgate; floral tubes 3–8 mm.
→ 13
13. Buds without free tips or with subapical free tips 1–2 mm, or with minute apical free tips less than 1 mm, and then bud pubescent but not glandular puberulent; plants branched or unbranched distally; stamens subequal.
C. brevipes
13. Buds with subapical free tips 1–2 mm, glandular puberulent; plants well branched; stamens differentiated into 2 sets.
C. confertiflora
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > 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. heterochroma, C. megalantha, C. multijuga, C. munzii, C. parryi, C. scapoidea, C. specicola, C. walkeri
Subordinate taxa
C. atwoodii, C. brevipes, C. claviformis, C. confertiflora, C. eastwoodiae, C. exilis, C. heterochroma, C. megalantha, C. multijuga, C. munzii, C. parryi, C. scapoidea, C. specicola, C. walkeri
Synonyms Camissonia section tetranthera, Oenothera section tetranthera Oenothera exilis, Camissonia exilis
Name authority unknown (P. H. Raven) W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 207. (2007)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers