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bur buttercup, hornseed buttercup, tubercled crowfoot

common water plantain buttercup, kidney-leaf buttercup, plantain-leaf buttercup, water-plantain buttercup

Roots

slender or fusiform-thickened basally, glabrous.

Stems

erect or ascending, not rooting nodally, villous, not bulbous-based.

erect or ascending, not rooting nodally, glabrous or hirsute.

Leaves

basal leaf blades with base acute;

proximal cauline leaf blades lanceolate, ovate, or elliptic, 1.8-14.1 × 0.7-2.9 cm, base acuminate to rounded, margins entire or serrulate, apex obtuse to acuminate.

Basal leaf

blades broadly spatulate in outline, 1-2x-dissected, 0.9-3.8 × 0.5-1.5 cm, segments linear, margins entire, apex obtuse to acuminate.

Inflorescences

bracts lanceolate.

Flowers

receptacle glabrous;

sepals spreading, 3-6 × 1-2 mm, villous;

petals yellow, 3-5 × 1-3 mm.

receptacle glabrous;

sepals 5, spreading or reflexed from base, 2-6 × 1-4 mm, glabrous or hirsute;

petals 5-12, 5-14 × 2-8 mm;

nectary scales glabrous.

Heads of achenes

cylindric, 9-16(-27) × 8-10 mm;

achenes 1.6-2 × 1.8-2 mm, tomentose;

beak persistent, lanceolate, 3.5-4.5 mm.

hemispheric to globose, 3-7 × 4-8 mm;

achenes 1.6-2.8 × 1.2-2 mm, glabrous or rarely hispid;

beak lance-subulate, straight or weakly curved, 0.4-1.2 mm.

Tuberous

roots absent.

Ranunculus testiculatus

Ranunculus alismifolius

Phenology Flowering spring (Apr–May).
Habitat Disturbed areas, especially in grassland
Elevation 400-2500 m (1300-8200 ft)
Distribution
from FNA
AZ; CA; CO; IA; ID; KS; MN; MO; MT; ND; NE; NM; NV; OH; OR; SD; UT; WA; WY; BC; SK; native to Eurasia [Introduced in North America]
[WildflowerSearch map]
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

In North America, Ranunculus testiculatus seems to be expanding its range rapidly in arid and semiarid areas. A second species of this subgenus, R. falcatus Linnaeus [Ceratocephala falcata (Linnaeus) Persoon], has been reported from North America, but all reports seem to be based on misidentified material of R. testiculatus.

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

Varieties 6 (6 in the flora).

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

Key
1. Petals 7–12 on most flowers, 2–3 mm broad.
var. montanus
1. Petals 4–6(–8), 2–8 mm broad.
→ 2
2. Stems 3.5–8 mm thick; leaf margins serrulate.
var. alismifolius
2. Stems 1–3 mm thick; leaf margins entire.
→ 3
3. Leaf blades ovate or elliptic.
var. alismellus
3. Leaf blades broadly to narrowly lanceolate.
→ 4
4. Petals 10–14 mm; California and Nevada.
var. lemmonii
4. Petals 5–8 mm; widespread.
→ 5
5. Roots fusiform-thickened proximally; stems and petioles glabrous or pubescent.
var. davisii
5. Roots not or scarcely fusiform-thickened proximally; stems and petioles glabrous.
var. hartwegii
Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Ranunculus > subg. Ceratocephala Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Flammula
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. pusillus, R. pygmaeus, R. ranunculinus, R. recurvatus, R. repens, R. rhomboideus, R. sabinei, R. sardous, R. sceleratus, R. sulphureus, R. trilobus, R. triternatus, R. turneri, R. uncinatus
R. abortivus, R. acriformis, R. acris, R. adoneus, 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. sceleratus, R. sulphureus, R. testiculatus, R. trilobus, R. triternatus, R. turneri, R. uncinatus
Subordinate taxa
R. alismifolius var. alismellus, R. alismifolius var. alismifolius, R. alismifolius var. davisii, R. alismifolius var. hartwegii, R. alismifolius var. lemmonii, R. alismifolius var. montanus
Synonyms Ceratocephalus orthoceras, Ceratocephalus testiculatus
Name authority Crantz: Stirp. Austr. Fasc. 2: 97. (1763) Geyer ex Bentham: Pl. Hartw., 295. (1849)
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