Chylismia claviformis

(Torrey & Frémont) A. Heller

Muhlenbergia 2: 105. 1906. (as Chylisma clavaeformis)

Basionym: Oenothera claviformis Torrey & Frémont in J. C. Frémont Rep. Exped. Rocky Mts., 314. 1845
Synonyms: Camissonia claviformis (Torrey & Frémont) P. H. Raven Chylismia scapoidea var. claviformis (Torrey & Frémont) Small O. scapoidea var. claviformis (Torrey & Frémont) S. Watson
Treatment appears in FNA Volume 10.

Herbs annual, glabrous, strigillose, glandular puber­ulent, or, sometimes, villous. Stems branched mostly from base, 3–70 cm. Leaves primarily in basal rosette, cauline reduced or absent, 1.5–20 × 0.3–3.5 cm; petiole 0.7–12 cm; blade usually pinnately lobed, sometimes lateral lobes poorly developed or absent, terminal lobe usually narrowly ovate to lanceolate, sometimes cor­date or subcordate, 0.8–9 × 0.2–4.5 cm, margins dentate, sinuate-dentate, or serrate, brown oil cells conspic­uously lining veins abaxially. Racemes nodding, elongating after anthesis. Flowers opening at sunset or sunrise; buds with or without subapical or apical free tips; floral tube 2–6.5 mm, villous inside proximally; sepals 2–8 mm; petals pale to bright yellow or white, sometimes red- or purple-dotted near base, fading purple, sometimes red or orange, or not changing color, 1.5–8 mm; stamens subequal, filaments 1.5–5.5 mm, anthers 1.5–6 mm, ciliate; style 5–16 mm, stigma exserted beyond anthers at anthesis. Capsules ascending to spreading, clavate, 8–40 mm; pedicel 4–40 mm. Seeds 0.6–1.5 mm.


w United States, nw Mexico.


Subspecies 11 (10 in the flora).

P. H. Raven (1962) subdivided this species into 12 subspecies and, subsequently (1969), he combined two of them. The latter approach is used here. Only subsp. wigginsii P. H. Raven does not occur in the United States; its narrow range is restricted to northern Baja California. Raven (1962, 1969) determined this species to be self-incompatible.

Chylismia claviformis is the most complex and, along with C. scapoidea, the most widely distributed species of the genus. The central part of its geograph­ical range is occupied by five closely related white-petaled subspecies (aurantiaca, claviformis, funerea, integrior, and peeblesii) that are very similar morphologically. South of this area four additional subspecies occur, all yellow-petaled (peirsonii, rubescens, wigginsii, and yumae). These four subspecies have sepals and petal color similar to those of C. brevipes, and P. H. Raven (1962, 1969) thought it likely that they were derived following hybridization between that species and one of the white-petaled populations of C. claviformis. North of the range of the white-petaled subspecies are found two additional yellow-petaled subspecies (cruciformis and lancifolia). Most populations of subsp. cruciformis consist of plants in which the flowers open in the early morning; in all other subspecies the flowers open in the late afternoon (Raven 1962, 1969). The following key will separate them, but there are many intergrades among the subspecies so that not all specimens will be easily identified.

Selected References



1 Herbs villous proximally; buds with subapical free tips; petals usually yellow, rarely white. > 2
2 Petals not changing color in fading, 4.5–7 mm; lateral lobes of leaf blades well developed. Chylismia claviformis subsp. peirsonii
2 Petals fading brick red, 3–5 mm; lateral lobes of leaf blades poorly developed, small or absent. Chylismia claviformis subsp. rubescens
1 Herbs strigillose, glandular puberulent, or glabrous proximally; buds with or without subapical or apical free tips; petals yellow or white. > 3
3 Petals yellow. > 4
4 Herbs strigillose, sometimes also glandular puberulent distally. Chylismia claviformis subsp. yumae
4 Herbs glabrous or glandular puberulent distally. > 5
5 Leaf blades with narrowly ovate to subcordate terminal lobes, at least some lateral lobes developed; flowers usually opening at dawn. Chylismia claviformis subsp. cruciformis
5 Leaf blades with lanceolate terminal lobes, lateral lobes usually greatly reduced or absent; flowers usually opening at dusk. Chylismia claviformis subsp. lancifolia
3 Petals usually white, rarely pale yellow (in subsp. claviformis). > 6
6 Herbs usually glabrous distally, rarely sparsely strigillose or glandular puberulent; lateral lobes of leaf blades usually well developed. Chylismia claviformis subsp. claviformis
6 Herbs usually strigillose and/or glandular puberulent, rarely glabrate; lateral lobes of leaf blades reduced, absent, or well developed. > 7
7 Lateral lobes of leaf blades well developed. > 8
8 Herbs strigillose, sometimes glabrate distally. Chylismia claviformis subsp. aurantiaca
8 Herbs glandular puberulent and strigillose. Chylismia claviformis subsp. peeblesii
7 Lateral lobes of leaf blades poorly developed, small, or absent. > 9
9 Leaf blades usually with at least some poorly developed lateral lobes; plants strigillose. Chylismia claviformis subsp. funerea
9 Leaf blades often with only terminal lobe developed; plants strigillose proximally, strigil-lose and glandular puberulent or glabrate distally. Chylismia claviformis subsp. integrior
... more about "Chylismia claviformis"
Warren L. Wagner +
(Torrey & Frémont) A. Heller +
Oenothera claviformis +
w United States +  and nw Mexico. +
Muhlenbergia +
Camissonia claviformis +, Chylismia scapoidea var. claviformis +  and O. scapoidea var. claviformis +
Chylismia claviformis +
Chylismia sect. Chylismia +
species +