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froststem suncup

Habit Herbs annual, densely villous and strigillose, glandular puberulent on distal parts. Herbs annual or biennial, villous, at least proximally, glabrous or even glaucous distally, rarely glandular puberulent.
Stems

well branched, 15–50 cm.

virgate with numerous divergent branches, 20–150 cm.

Leaves

in well-developed basal rosette and also cauline, 7–20 × 1.5–2.5 cm;

petiole 1–4(–8) cm;

blade pinnately lobed, terminal lobe oblanceolate to narrowly ovate, 2.5–5 × 1–2.5 cm, margins irregularly dentate, oil cells on abaxial surface inconspicuous.

primarily in well-developed basal rosette, cauline reduced or absent, 6–30 × 1.4–6.5 cm;

petiole 0.3–6 cm;

blade pinnately or bipinnately lobed, terminal lobe ovate to elliptic, 2.5–6.5 × 1.5–3 cm, margins irregularly serrate, dark brown oil cells prominently lining veins abaxially.

Racemes

nodding, dense, mostly elongating after flowers open.

erect to nodding, elongating in bud.

Flowers

opening at sunrise;

buds with conspicuous, subapical free tips 1–2 mm;

floral tube 3–5 mm, short-villous inside proximally;

sepals 9–12 mm;

petals bright yellow, with red dots at base, fading lavender, 12–18 mm;

stamens unequal, filaments of antisepalous stamens 6–8 mm, those of antipetalous ones 4–5 mm, anthers 4–6 mm, ciliate;

style 11–18 mm, stigma exserted beyond anthers at anthesis.

opening at sunrise;

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

floral tube 1–3 mm, glabrous or villous inside proximally;

sepals 3–8 mm;

petals usually bright yellow, rarely cream, fading yellow to lavender, 4–9 mm;

stamens unequal, filaments of antisepalous stamens 2.5–4 mm, those of antipetalous ones 1.3–3 mm, anthers 2–4 mm, ciliate;

style 7–11 mm, stigma exserted beyond anthers at anthesis.

Capsules

ascending or spreading, oblong-cylindrical, immature capsule to 35 mm;

pedicel 5–15 mm.

usually spreading, rarely slightly reflexed, oblong-cylindrical, 10–52 mm;

pedicel 7–20 mm.

Seeds

not known.

1–1.3 mm.

2n

= 14.

Chylismia confertiflora

Chylismia multijuga

Phenology Flowering Apr–May. Flowering Mar–Jun(–Sep).
Habitat Cinder soil. Forming colonies on rocky slopes and banks of eroded sedimentaries, on gypsum or limestone, on conglomerates, often with Juniperus and Pinus edulis, with Encelia farinosa and Larrea.
Elevation 1300–1400 m. (4300–4600 ft.) 300–1100 m. (1000–3600 ft.)
Distribution
from FNA
AZ
[BONAP county map]
from FNA
AZ; NV; UT
[WildflowerSearch map]
[BONAP county map]
Discussion

Chylismia confertiflora is known only from the type locality on the east side and base of Vulcan’s Throne, Toroweap Valley, Grand Canyon National Monument in Mohave County. P. H. Raven (1962, 1969) assumed this species to be self-incompatible, based on the large flowers with the stigma elevated above the anthers.

A. Cronquist et al. (1997c) treated Chylismia confertiflora as part of C. brevipes, with a comment about the capsule dimensions, and indicated they consider the differences to be one end of the spectrum of a variation within C. brevipes. Although known from very few collections and sparse field data, P. H. Raven (1962, 1969) considered it to be distinct and to be most closely related to C. brevipes and to C. multijuga. He distinguished it from the latter by its larger flowers, nodding inflorescences, and large buds; and from the former by its glandular puberulent sepals, unequal stamens, and uniformly branched habit. In addition, the very restricted range of C. confertiflora is outside (to the east) of the range of C. brevipes. Chylismia multijuga grows within a few miles of the only know locality, but in this area C. confertiflora is very distinct from that species. Further collections and more detailed study of the overall morphological patterns as well as, perhaps, molecular data may clarify whether this is best considered to be an extremely restricted distinct species or a somewhat distinct outlier of the variable C. brevipes.

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

Chylismia multijuga is known from Washington County, Utah, and southern Lincoln County, Nevada, to northern Mohave County, Arizona. P. H. Raven (1962, 1969) determined this species to be self-incompatible. It hybridizes with C. brevipes subspp. brevipes and pallidula.

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

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. eastwoodiae, C. exilis, C. heterochroma, C. megalantha, C. multijuga, C. munzii, C. parryi, C. scapoidea, C. specicola, C. walkeri
C. arenaria, C. atwoodii, C. brevipes, C. cardiophylla, C. claviformis, C. confertiflora, C. eastwoodiae, C. exilis, C. heterochroma, C. megalantha, C. munzii, C. parryi, C. scapoidea, C. specicola, C. walkeri
Synonyms Oenothera confertiflorap., Camissonia confertiflora Oenothera multijuga, Camissonia multijuga, Chylisma hirta, C. parviflora, C. venosa, O. brevipes var. multijuga, O. brevipes var. parviflora, O. multijuga var. parviflora, O. phlebophylla, O. watsonii
Name authority (P. H. Raven) W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 207. (2007) (S. Watson) Small: Bull. Torrey Bot. Club 23: 193. (1896) — (as Chylisma)
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