Ranunculus sect. Arcteranthis

(Greene) L. D. Benson

Amer. J. Bot. 23: 174. 1936.

Basionym: Undefined sect. Arcteranthis Greene Pittonia 3: 190. 1897
Treatment appears in FNA Volume 3.

Plants glabrous. Stems erect, not bulbous-based, without bulbils. Roots basal, never tuberous. Leaves all basal or sometimes with single, scalelike, cauline leaf; basal leaves petiolate, blades 3-5-parted, segments again lobed and crenate; cauline leaf (when present) petiolate or sessile, blade small, palmately or pedately 3-9-lobed. Inflorescences terminal, solitary flowers. Flowers: sepals deciduous soon after anthesis, 5; petals yellow, showy; nectary scale a crescentic ridge surrounding nectary, glabrous, free margin entire; style present. Fruits achenes, 1-locular; achene body cylindric, 1.4-2 times as wide as thick, not prolonged beyond seed; wall thin, papery, loose, compressed, at maturity forming narrow ventral wing, longitudinally veined; margin an inconspicuous ridge similar to veins; beak 1-1.8 mm, much shorter than achene body.

Distribution

nw North America

Discussion

Species 1 (1 in the flora).

Selected References

None.

not prolonged +
1.4-2 times as wide as thick +
Alan T. Whittemore +
(Greene) L. D. Benson +
cuneate +, truncate +  and cordate +
Undefined sect. Arcteranthis +
curved +  and straight +
0.1 cm1 mm <br />0.001 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
3-9-lobed;3-5-parted +
large +  and small +
globose;cylindric +
sessile;petiolate +
2-50-flowered +
0 cm0 mm <br />0 m <br /> (25 cm250 mm <br />0.25 m <br />) +
nw North America +
sessile +  and pedicellate +
showy +  and inconspicuous +
sessile +  and aggregate +
cylindric;obovoid;cylindric;obovoid;globose;lenticular;discoid +
axillary +  and terminal +
reniform +  and linear +
petiolate +, compound +  and simple +
whorled +, opposite +  and alternate +
cauline +  and basal +
parted +  and lobed +
palmate +  and pinnate +
toothed;crenate;toothed;crenate;entire +
distinct +
linear +  and orbiculate +
reduced +
0.1 cm1 mm <br />0.001 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
4 +  and 250 +
Amer. J. Bot. +
inconspicuous +
crescentic +
not arillate +  and stalked +
crenate +  and lobed +
white;yellow;white;yellow;purple;sometimes;green +
deciduous +
distinct +
oblong +  and elliptic ovate or lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
(5-)10-many +
not bulbous-based +
persistent +
Ranunculus sect. Arcteranthis +
Ranunculus subg. Cyrtorhyncha +
section +
compressed +
perennial +  and annual +
herbaceous +  and woody +