Oenothera laciniata
Oenothera coloradensis
cut-leaf evening-primrose, southern evening primrose
Colorado beeblossom
erect to ascending, unbranched to much branched, 5–50 cm.
1–few-branched from base, 50–80(–100) cm.
in a basal rosette and cauline, basal 4–15 × 1–3 cm, cauline 2–10 × 0.5–3.5 cm;
blade green, narrowly oblanceolate to narrowly elliptic or narrowly oblong, margins usually dentate or deeply lobed;
bracts spreading, flat.
in a basal rosette and cauline, basal 4–18 × 1.5–4 cm, blade very narrowly elliptic, lanceolate, or oblanceolate;
cauline 5–13 × 1–4 cm, blade narrowly elliptic, narrowly lanceolate, or narrowly oblanceolate, margins subentire or repand-denticulate.
usually 1 opening per day near sunset;
buds erect, with free tips erect, 0.3–3 mm;
floral tube 12–35 mm;
sepals 5–15 mm;
petals yellow, fading orange or reddish tinged, broadly obovate or obcordate, 5–22 mm;
filaments 3–14 mm, anthers 4–5 mm, pollen ca. 50% fertile;
style 20–50 mm, stigma surrounded by anthers at anthesis.
4-merous, zygomorphic, opening at sunset;
floral tube 8–12 mm;
sepals 9.5–13 mm;
petals white, fading pink, rhombic-obovate, 7–12 mm;
filaments 6.5–9 mm, anthers 2.5–4 mm, pollen 90–100% fertile;
style 19–25 mm, stigma exserted beyond anthers at anthesis.
cylindrical, sometimes slightly enlarged toward apex, 20–50 × 2–4 mm.
ellipsoid or ovoid, sharply 4-angled, with fairly deep furrows alternating with angles, 6–8.5 × 2–3 mm;
sessile.
ellipsoid to subglobose, 0.9–1.8 × 0.4–0.9 mm.
1–4, yellowish to light brown, 2–3 × 1 mm.
= 14.
= 14.
Oenothera laciniata
Oenothera coloradensis
Oenothera laciniata is a PTH species and forms aring of 14 chromosomes in meiosis, and is self-compatible and autogamous (W. Dietrich and W. L. Wagner 1988).
Oenothera laciniata is known in New Mexico from Doña Ana and Roosevelt counties from non-montane habitats and thus do not appear to represent O. pubescens; however, a few collections from Brewster and Jeff Davis counties, Texas, reported by W. Dietrich and W. L. Wagner (1988) as O. laciniata appear to represent collections of O. pubescens. Dietrich and Wagner found that O. laciniata hybridizes not only with O. grandis, but also with O. drummondii subsp. drummondii, O. humifusa, and O. mexicana. It is naturalized nearly worldwide in temperate and subtropical areas.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Oenothera coloradensis is currently known from fewer than two dozen populations from southern Laramie and Platte counties in Wyoming, northern Weld County, Colorado, formerly near Fort Collins, Larimer County, Colorado, and in western Kimball County, Nebraska. It is federally listed as a threatened species in the United States. The primary threats are agricultural use of habitat, herbicide spraying to control weed species, and livestock trampling and grazing (see W. L. Wagner et al. 2013). Recent study by K. N. Krakos (unpubl.) has determined this species to be self-compatible. P. H. Raven and D. P. Gregory (1972[1973]) described this species as glandular puberulent in inflorescence, which was repeated in the recent revised taxonomy (Wagner et al.); however, examination of specimens show that P. A. Munz (1965) was correct in describing the pubescence of the inflorescence as non-glandular.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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