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Allegheny crowfoot, Allegheny Mountain buttercup

Habit Plants glabrous or sometimes pilose or pubescent.
Roots

slender, 0.2-0.8 mm thick.

basal, sometimes tuberous.

Stems

erect or nearly erect, 10-50 cm, glabrous, each with 9-40 flowers.

erect, not bulbous-based, without bulbils.

Leaves

basal and cauline, simple or compound;

basal leaves petiolate, blades variously divided, unlobed to deeply parted, compound, or filiform-dissected, segments undivided or again lobed or parted, margins entire or crenate, never serrate;

cauline leaves sessile to nearly sessile or sometimes with much shorter petioles than basal leaves, blades lobed to compound or dissected (rarely unlobed in R. macauleyi and R. glaberrimus).

Basal leaves

persistent, blades reniform, outer undivided, inner 3-lobed to 3-foliolate, 1-3.5 × 1.5-4.5 cm, base truncate or cordate, margins crenate, apex rounded or obtuse.

Inflorescences

1-50-flowered cymes.

Flowers

pedicels pubescent or glabrous;

receptacle sparsely pilose;

sepals 2-3 × 1-2 mm, abaxially sparsely hispid, hairs colorless;

petals 5, 1-2 × 0.5-1 mm;

nectary scale glabrous.

pedicellate;

sepals deciduous soon after anthesis, 5;

petals yellow (rarely absent in R. pedatifidus);

nectary scale joined with petal on 3 sides, forming pocket enclosing nectary (sometimes with apex free, forming flap shorter than pocket), glabrous or setose, free margin entire or fringed;

style present.

Fruits

achenes, 1-locular;

achene body thick-lenticular or asymmetrically thick-lenticular to compressed-globose, 1.2-2 times as wide as thick, not prolonged beyond seed;

wall thick, smooth;

margin low narrow ridge, often inconspicuous;

beak much shorter than achene body.

Heads of achenes

globose to ovoid, 3-7 × 3-5 mm;

achenes 1.5-2 × 1.4-1.8 mm, glabrous;

beak slender, strongly curved, 0.6-1 mm.

2n

= 16.

Ranunculus allegheniensis

Ranunculus sect. Epirotes

Phenology Flowering spring–summer (Apr–Jul).
Habitat Woods and pastures
Elevation 0-1100 m (0-3600 ft)
Distribution
from FNA
CT; KY; MA; MD; NC; NY; OH; PA; RI; TN; VA; VT; WV
[WildflowerSearch map]
[BONAP county map]
Worldwide except lowland tropics
Discussion

Species ca. 70 (22 in the flora).

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

Key
1. Abaxial surface of sepals with dense brown pubescence.
→ 2
1. Abaxial surface of sepals glabrous or with colorless hairs.
→ 4
2. Basal leaf blades narrowly elliptic to lanceolate or oblanceolate; s Rocky Mountains.
R. macauleyi
2. Basal leaf blades orbiculate to reniform; Canadian Rocky Mountains and Arctic.
→ 3
3. Receptacle brown-pilose; basal leaf blades usually shallowly lobed, or unlobed with crenate margins.
R. sulphureus
3. Receptacle glabrous; basal leaf blades 3-parted.
R. nivalis
4. Basal leaves deciduous before anthesis; nectary scale ciliate, petals 2–3 times as long as wide.
R. arizonicus var. arizonicus
4. Basal leaves persistent; nectary scale glabrous, (glabrous or ± pilose in R. cardiophyllus and R. glaberrimus, which have petals 1–1.5 times as long as wide).
→ 5
5. Some or all basal leaf blades unlobed.
→ 6
5. All basal leaf blades lobed or parted.
→ 14
6. Basal leaf margins entire or with 3 broad shallow rounded teeth; heads of achenes globose, 6–20mm wide.
R. glaberrimus
6. Basal leaf margins either crenate to crenate-lobulate, with more than 5 rounded teeth, or innermost teeth lobed or divided; heads of achenes usually ovoid to cylindric (sometimes globose and 3–8 mm wide).
→ 7
7. Petals 1–3.5 mm.
→ 8
7. Petals 4–18 mm.
→ 10
8. Stems villous, sometimes sparsely so; receptacle glabrous; base of some roots ± swollen and tuberous, usually 1–2 mm thick; leaf base usually obtuse or truncate.
R. micranthus
8. Stems glabrous; receptacle pilose, sometimes sparsely so; base of roots never much swollen, 0.2–1.5 mm thick; leaf base ± cordate.
→ 9
9. Sepals hispid; achene beak 0.6–1 mm.
R. allegheniensis
9. Sepals glabrous; achene beak 0.1–0.2 mm.
R. abortivus
10. Leaf blades wider than long; e of Great Plains, not in Great Lakes area.
→ 11
10. Leaf blades at least as long as wide; Great Lakes area and Great Plains w to Great Basin.
→ 12
11. Pedicels glabrous (see also R. escholtzii with lobed leaves); se United States.
R. harveyi var. harveyi
11. Pedicels pubescent, sometimes sparsely so; e Canada.
R. allenii
12. Sepals 5–8 × 3–7 mm; nectary scale ciliate, sometimes glabrous; leaf base cordate to broadly obtuse.
R. cardiophyllus
12. Sepals 3–6× 1.5–3mm; nectary scale glabrous; leaf base obtuse or acute to rounded.
→ 13
13. Basal leaf blades ovate, obovate, or orbiculate; heads of achenes cylindric, 7–17 mm; achene beak 0.4–2 mm; Rocky Mountains, Great Basin, and Black Hills.
R. inamoenus
13. Basal leaf blades ovate to rhombic; heads of achenes depressed-globose, 4–6 mm; achene beak 0.2– 0.3 mm; n Great Plains and eastward.
R. rhomboideus
14. Basal leaf blades dissected into linear segments.
→ 15
14. Basal leaves at most 1×-divided, segments not linear.
→ 16
15. Roots slender, 0.8–1.4 mm thick; achene beak 1.2–1.7 mm.
R. adoneus
15. Roots 2–3 mm thick; achene beak 0.8–1.5 mm.
R. triternatus
16. Some roots clavate and tuberous, 2.5–5 mm thick; basal leaf blades deeply divided into 3 oblanceolate segments.
R. jovis
16. Roots not clavate or tuberous, 0.1–1.6 mm thick; leaves various but not as above.
→ 17
17. Petals 7–15 mm.
→ 18
17. Petals 1–8 mm.
→ 20
18. Pedicels glabrous.
R. eschscholtzii
18. Pedicels pubescent.
→ 19
19. Heads of achenes globose to short-ovoid; basal leaves 3-parted with segments again lobed or parted, margins toothed; Greenland.
R. auricomus
19. Heads of achenes cylindric; basal leaves pedately (5–)7(–9)-parted or -divided, segments sometimes again lobed, margins never toothed; throughout n North America.
R. pedatifidus var. affinis
20. Flowering stems 0.6–3.5 cm (sometimes longer in fruit); petals 1–3.5 mm.
R. pygmaeus
20. Flowering stems (1–)4–15(–27) cm; petals 3–8 mm.
→ 21
21. Petals 6–16 mm; beak of achene straight, 0.6–1.8 mm; pedicels glabrous.
R. eschscholtzii
21. Petals 4–8 mm; beak of achene straight or curved, 0.3–0.7 mm; pedicels glabrous or pilose.
→ 22
22. Base of basal leaves obtuse; petals 5–8 mm; arctic Alaska, Canada, and Greenland.
R. sabinei
22. Base of basal leaves nearly cordate to truncate; petals 4–5 mm; Alaska, Yukon, and Rocky Mountains.
R. gelidus
Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Ranunculus > subg. Ranunculus > sect. Epirotes Ranunculaceae > Ranunculus > subg. Ranunculus
Sibling taxa
R. abortivus, R. acriformis, R. acris, R. adoneus, R. alismifolius, 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. abortivus, R. adoneus, R. allegheniensis, R. allenii, R. arizonicus var. arizonicus, R. auricomus, R. cardiophyllus, R. eschscholtzii, R. gelidus, R. glaberrimus, R. harveyi var. harveyi, R. inamoenus, R. jovis, R. macauleyi, R. micranthus, R. nivalis, R. pedatifidus var. affinis, R. pygmaeus, R. rhomboideus, R. sabinei, R. sulphureus, R. triternatus
Synonyms R. section Marsypadenium
Name authority Britton: Bull. Torrey Bot. Club 22: 224. (1895) (Prantl) L. D. Benson: Amer. J. Bot. 23: 169. (1936)
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