Ranunculus orthorhynchus

Stems nearly erect or decumbent, never rooting nodally, hispid, strigose, or glabrous, base not bulbous. Roots sometimes fleshy and ± tuberous. Basal leaf blades narrowly ovate to oblong or semicircular in outline, simple to 3-5-lobed or -foliolate, 2.8-12.5 × 2.5-14 cm, leaflets or segments undivided or 1-2×-lobed or -parted, ultimate segments circular to linear, margins dentate, crenate, or entire, apex rounded to narrowly acute. Flowers: receptacle hispid; sepals reflexed 1-2 mm above base, 5-11 × 2-4 mm, hispid, hirsute, or glabrous; petals 5-6, abaxially yellow or red, adaxially yellow, 8-18 × 4-11 mm. Heads of achenes hemispheric to ovoid, 5-13 × 6-10 mm; achenes 2.8-4.5 × 1.8-3.2 mm, glabrous, margin forming narrow rib 0.1-0.2 mm wide; beak persistent, narrowly lanceolate to subulate, straight, 1.8-3.8(-4.8) mm.

Distribution

w North America.

Discussion

Varieties 3

The first two varieties (Ranunculus orthorhynchus var. orthorhynchus and R. orthorhynchus var. platyphyllus) are rather weak, intergrading extensively in California and Oregon. By contrast, R. orthorhynchus var. bloomeri often grows with the others with little or no intergradation (although intermediate populations are found in some areas), and it has been treated as a distinct species, R. bloomeri, by many taxonomists.

Selected References

None.

Lower Taxa

Ranunculus orthorhynchus var. bloomeri, Ranunculus orthorhynchus var. orthorhynchus, Ranunculus orthorhynchus var. platyphyllus

Key

1	Basal leaves simple or 3-foliolate, if compound then leaflets undivided, margins crenate; petals retuse.	Ranunculus orthorhynchus var. bloomeri
1	Basal leaves 3–5-foliolate, leaflets lobed or parted, margins entire or dentate; petals truncate or rounded.	> 2
2	Heads of achenes hemispheric or sometimes globose, 5–7 mm; petals often abaxially red.	Ranunculus orthorhynchus var. orthorhynchus
2	Heads of achenes globose or ovoid, 8–13 mm; petals yellow.	Ranunculus orthorhynchus var. platyphyllus