All Floras      Advanced Search
FNA Vol. 3 Login | eFloras Home | Help
FNA | Family List | FNA Vol. 3 | Ranunculaceae

2a.1. Ranunculus Sect. Ranunculus Linnaeus

Ranunculus sect. Chrysanthe (Spach) L. D. Benson

Plants usually ± hispid, sometimes glabrous. Stems erect to decumbent, sometimes stoloniferous, sometimes bulbous-based, without bulbils. Roots basal, sometimes also nodal, sometimes tuberous. Leaves basal and cauline, petiolate; basal deeply parted or compound (except sometimes in R . orthorhynchus var. bloomeri ), blades with segments lobed or parted, margins toothed; cauline deeply parted or compound, similar to basal or with shorter petioles and/or blades with narrower segments (rarely poorly developed in R . fascicularis ). Inflorescences 1-50-flowered cymes. Flowers pedicellate; sepals deciduous soon after anthesis, 5 (sometimes 6 in R . occidentalis var. hexasepalus ); petals always present, yellow, sometimes abaxially reddish, rarely poorly developed; nectary scale attached basally, free from petal for at least 1/2 its length, forming flap covering nectary (or sometimes attached on 3 sides, forming pocket in R . recurvatus ), glabrous, free margin entire; style present. Fruits achenes, 1-locular; achene body discoid, strongly flattened, 3-15 times as wide as thick, not prolonged beyond seed; wall thick, not ornamented; margin low or high narrow ridge or wing; beak much shorter than achene body.

Species ca. 100 (19 in the flora): worldwide except lowland tropics.

1 Petals 2-6 mm, usually no longer than sepals (sometimes longer than sepals in R. uncinatus).   (2)
+ Petals (6-)7-26 mm (rarely shorter in R. occidentalis and R. canus, in which petals are much longer than sepals).   (5)
2 (1) Basal leaves simple and lobed or parted.   (3)
+ Basal leaves compound.   (4)
3 (2) Receptacle glabrous; base of stem not bulbous; w North America.   1 Ranunculus uncinatus
+ Receptacle hispid; base of stem bulbous, cormlike; e North America.   2a var. recurvatus
4 (2) Petals 2-4 × 1-2.5 mm; heads of achenes cylindric, 5-7 mm wide.   3 Ranunculus pensylvanicus
+ Petals 4-6 × 3.5-5 mm; heads of achenes globose to ovoid, 7-10 mm wide.   4 Ranunculus macounii
5 (1) Sepals spreading, sometimes reflexed from base with age.   (6)
+ Sepals reflexed along well-defined transverse fold 1-3 mm above base.   (12)
6 (5) Basal leaves deeply parted or dissected, ultimate segments linear to broadly linear, margins entire (occasionally a lobe reduced to large tooth); Rocky Mountains.   8a var. acriformis
+ Basal leaves variously parted or compound but not as above, segments seldom linear, margins toothed; widespread.   (7)
7 (6) Leaf blades simple, 3-5-parted or -divided.   (8)
+ Leaf blades 3-5-foliolate.   (9)
8 (7) Basal leaf blades pentagonal in outline; beak of achene 0.2-1 mm; widespread.   7 Ranunculus acris
+ Basal leaf blades cordate to reniform in outline; beak of achene 1.6-2 mm; Mackenzie Delta to ne Alaska.   6 Ranunculus turneri
9 (7) Tuberous roots present.   (10)
+ Tuberous roots absent.   (11)
10 (9) Petals 10-22; c Texas.   15 Ranunculus macranthus
+ Petals 5(-7); widespread, e North America.   16 Ranunculus fascicularis
11 (9) Beak of achene curved, 0.8-1.2 mm; stems decumbent to creeping.   18 Ranunculus repens
+ Beak of achene straight or somewhat curved, 0.8-2.6 mm; stems erect to decumbent.   17 Ranunculus hispidus
12 (5) Petals 8-22; Pacific Coast, Arizona, Texas.   (13)
+ Petals 5-7; widespread.   (17)
13 (12) Tuberous roots absent; beak of achene lanceolate to deltate-apiculate, curved, 0.2-1.6 mm; California to British Columbia.   (14)
+ Tuberous roots present; beak of achene subulate, straight, (1.8-)2-4 mm (but sometimes deciduous); Texas, Arizona.   (16)
14 (13) Achenes 3.4-4.2 mm, beak deltate or lance-deltate; Transverse Ranges, s California.   11b var. ludovicianus
+ Achenes 1.8-3.2 mm, beak lanceolate; California to British Columbia.   12 Ranunculus californicus
15 Beak of achene 1.2-1.6 mm; sepals 5-6; Queen Charlotte Islands, British Columbia.   9f var. hexasepalus
+ Beak of achene 0.2-0.8 mm; sepals 5; California, Oregon, Mexico.   12 Ranunculus californicus
16 (13) Petals 2-5 mm wide; achenes 2-2.4 mm wide, margins forming ribs or narrow wings 0.1-0.4 mm wide; sepals always reflexed; Arizona, trans-Pecos Texas.   14 Ranunculus fasciculatus
+ Petals 4-9 mm wide; achenes 2.8-3.4 mm wide, margins forming narrow ribs 0.4-0.6 mm wide; sepals spreading or weakly reflexed; Edwards Plateau, Texas.   15 Ranunculus macranthus
17 (12) Receptacle glabrous; basal leaves 3-parted or -foliolate, segments or leaflets linear to cuneate.   (18)
+ Receptacle hispid; basal leaves usually pinnately 3-7-foliolate (sometimes merely 3-parted with orbiculate to ovate segments in Ranunculus orthorhynchus var. bloomeri).   (21)
18 (17) Beak of achene deltate or lance-deltate, curved; Sacramento Valley, California.   11a var. canus
+ Beak of achene lanceolate to lance-subulate, straight or curved; widespread.   (19)
19 (18) Basal leaves deeply 3-divided, segments again deeply parted, ultimate segments linear or nearly so; Rocky Mountains.   8b var. montanensis
+ Basal leaves deeply 3-parted to 3-foliolate, margins of segments or leaflets toothed or shallowly lobed, ultimate lobe triangular or broadly lanceolate; Pacific Slope.   (20)
20 (19) Petals yellow on both surfaces; widespread.   9 Ranunculus occidentalis
+ Petals reddish abaxially; sw Oregon.   10 Ranunculus austro-oreganus
21 (17) Beak of achene oblong or triangular, curved, 0.2-0.8 mm; introduced weeds.   (22)
+ Beak of achene lanceolate or subulate, straight or somewhat curved (sometimes tip weakly hooked in R. pacificus), (0.8-)1-3.8(-4.8) mm; native.   (23)
22 (21) Base of stem bulbous, cormlike; petals 9-13 × 8-11 mm.   19 Ranunculus bulbosus
+ Base of stem not bulbous; petals 7-10 × 4-8 mm.   20 Ranunculus sardous
23 (21) Stems decumbent, sometimes rooting at nodes; e North America.   17c var. nitidus
+ Stems erect to decumbent, never rooting at nodes; w North America.   (24)
24 (23) Beak of achene 1-1.8 mm; leaflets lobed; Alaska panhandle.   5 Ranunculus pacificus
+ Beak of achene 2-3.8(-4.8) mm (1.8-2.2 mm in var. bloomeri, with unlobed leaflets); throughout w North America.   13 Ranunculus orthorhynchus

  • List of lower taxa


  •  |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |