Habit: Annual, from taproot, stems rarely present, to 25 mm.
Leaf: mostly basal, or cauline on short stems, alternate, broadly sessile or clasping.
Inflorescence: flowers 1 in axils of rosette, nodding in bud.
Flower: opening at dawn; sepals 4, reflexed in pairs; petals 4, yellow, unspotted, strongly ultraviolet-reflective, fading red-orange; longer stamens opposite sepals, anthers attached near base, pollen grains 3-angled; ovary tip with sterile 0.4--18 cm projection that often breaks off in fruit, with clear abscission line at juncture between short hypanthium and fertile part of ovary, stigma hemispheric, +- = anthers and generally self-pollinated (or > anthers and cross-pollinating).
Fruit: irregularly obovoid, sharply 4-angled with pointed wing near center top of each valve, +- sessile, very tardily dehiscent in distal 1/2 only, thick-walled (not distended by seeds), persistent for > 1 year, sessile.
Seed: in 2 crowded rows per chamber, obovoid to narrowly obovoid, finely papillate or deeply pitted, tan or brown with dark patches.
Species In Genus: 2 species: California, disjunct in northwestern Nevada, southern Oregon, northern Baja California.
Etymology: (Greek: four winged)
Note: Incl in
Camissonia in TJM (1993).
Jepson eFlora Author: Warren L. Wagner & Peter C. Hoch, family description, key to genera, treatment of genera by Warren L. Wagner
Reference: Wagner et al. 2007 Syst Bot Monogr 83:1--240
Unabridged Reference: Raven 1969 Contr US Natl Herb 37:161--396Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)Key to Tetrapteron
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