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low buttercup, low spearwort, weak buttercup

blister buttercup, celery-leaf buttercup, celery-leaf crowfoot, cursed buttercup, cursed crowfoot, cursed crowsfoot, renoncule scélérate

Roots

not thickened basally, glabrous.

Stems

erect or ascending, rooting at most proximal nodes, glabrous.

erect, glabrous, rooting at base, only very rarely rooting at proximal nodes.

Leaves

basal and cauline, basal and proximal cauline leaf blades reniform to semicircular in outline, 3-lobed or -parted, 1-5 × 1.6-6.8 cm, base truncate to cordate, segments usually again lobed or parted, sometimes undivided, margins crenate or crenate-lobulate, apex rounded or occasionally obtuse.

Proximal cauline leaf blades

ovate or lanceolate, 1.2-4.2 × 0.5-1.2 cm, base acute to truncate, margins entire or denticulate, apex acuminate to rounded.

Inflorescences

bracts linear to lanceolate or oblanceolate.

Flowers

receptacle glabrous;

sepals 4-5, spreading or reflexed from base, 1.5-3 × 1-1.5 mm, glabrous or sparsely hirsute;

petals 1-3, 1.5-2 × 0.5-1 mm;

nectary scales glabrous.

receptacle pubescent or glabrous;

sepals 3-5, reflexed from or near base, 2-5 × 1-3 mm, glabrous or sparsely hirsute;

petals 3-5, 2-5 × 1-3 mm;

nectary on petal surface, scale poorly developed and forming crescent-shaped or circular ridge surrounding but not covering nectary;

style absent.

Heads of achenes

hemispheric to cylindric, 2-8 × 2-3 mm;

achenes 1-1.2 × 0.6-0.8 mm, ± tuberculate, glabrous;

beak absent or nearly so, to 0.1 mm.

ellipsoid or cylindric heads, 5-13 × 3-7 mm;

achenes 1-1.2 × 0.8-1 mm, glabrous;

beak deltate, usually straight, 0.1 mm.

Ranunculus pusillus

Ranunculus sceleratus

Phenology Flowering spring (Apr–Jun).
Habitat Ditches, ponds, and swamps
Elevation 0-300 m (0-1000 ft)
Distribution
from FNA
AL; AR; CA; DC; DE; FL; GA; IL; IN; KY; LA; MD; MO; MS; NC; NJ; NY; OH; OK; PA; SC; TN; TX; VA; WV
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; QC; SK; YT; Eurasia
[WildflowerSearch map]
[BONAP county map]
Discussion

In most specimens of Ranunculus pusillus, the heads of achenes are hemispheric to short-ovate and only 2-3 mm. Occasional plants with cylindric heads of achenes 4-6 mm from the Gulf Coast states have been called R. pusillus var. angustifolius.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 2 (2 in the flora).

Ranunculus sceleratus varieties were used by the Thompson Indians as a poison for their arrow points (D. E. Moerman 1986).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Faces of achene with fine transverse wrinkles; leaf blades lobed or parted, segments undivided or lobed, margins crenate.
var. sceleratus
1. Faces of achene smooth; leaf blades always parted (often deeply so), segments lobed or parted, margins deeply crenate or lobulate.
var. multifidus
Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Flammula Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Hecatonia
Sibling taxa
R. abortivus, R. acriformis, R. acris, R. adoneus, R. alismifolius, R. allegheniensis, R. allenii, R. ambigens, R. andersonii, R. aquatilis, R. arizonicus, R. arvensis, R. auricomus, R. austro-oreganus, R. bonariensis, R. bulbosus, R. californicus, R. canus, R. cardiophyllus, R. cooleyae, R. cymbalaria, R. eschscholtzii, R. fascicularis, R. fasciculatus, R. ficaria, R. flabellaris, R. flammula, R. gelidus, R. glaberrimus, R. glacialis, R. gmelinii, R. gormanii, R. harveyi, R. hebecarpus, R. hederaceus, R. hispidus, R. hydrocharoides, R. hyperboreus, R. hystriculus, R. inamoenus, R. jovis, R. kamtschaticus, R. lapponicus, R. laxicaulis, R. lobbii, R. macauleyi, R. macounii, R. macranthus, R. marginatus, R. micranthus, R. muricatus, R. nivalis, R. occidentalis, R. oresterus, R. orthorhynchus, R. pacificus, R. pallasii, R. parviflorus, R. pedatifidus, R. pensylvanicus, R. platensis, R. populago, R. pygmaeus, R. ranunculinus, R. recurvatus, R. repens, R. rhomboideus, R. sabinei, R. sardous, R. sceleratus, R. sulphureus, R. testiculatus, R. trilobus, R. triternatus, R. turneri, R. uncinatus
R. abortivus, R. acriformis, R. acris, R. adoneus, R. alismifolius, R. allegheniensis, R. allenii, R. ambigens, R. andersonii, R. aquatilis, R. arizonicus, R. arvensis, R. auricomus, R. austro-oreganus, R. bonariensis, R. bulbosus, R. californicus, R. canus, R. cardiophyllus, R. cooleyae, R. cymbalaria, R. eschscholtzii, R. fascicularis, R. fasciculatus, R. ficaria, R. flabellaris, R. flammula, R. gelidus, R. glaberrimus, R. glacialis, R. gmelinii, R. gormanii, R. harveyi, R. hebecarpus, R. hederaceus, R. hispidus, R. hydrocharoides, R. hyperboreus, R. hystriculus, R. inamoenus, R. jovis, R. kamtschaticus, R. lapponicus, R. laxicaulis, R. lobbii, R. macauleyi, R. macounii, R. macranthus, R. marginatus, R. micranthus, R. muricatus, R. nivalis, R. occidentalis, R. oresterus, R. orthorhynchus, R. pacificus, R. pallasii, R. parviflorus, R. pedatifidus, R. pensylvanicus, R. platensis, R. populago, R. pusillus, R. pygmaeus, R. ranunculinus, R. recurvatus, R. repens, R. rhomboideus, R. sabinei, R. sardous, R. sulphureus, R. testiculatus, R. trilobus, R. triternatus, R. turneri, R. uncinatus
Subordinate taxa
R. sceleratus var. multifidus, R. sceleratus var. sceleratus
Synonyms R. oblongifolius, R. pusillus var. angustifolius, R. tener Hecatonia scelerata
Name authority Poiret: in J. Lamarck et al., Encycl. 6: 99. (1804) Linnaeus: Sp. Pl. 1: 551. (1753)
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