Ranunculus sceleratus

The foliage of Cursed Crowfoot is more toxic than most Ranunculus spp. (buttercups). During earlier times, beggars reportedly smeared the juices of the foliage on their faces and arms to create blisters that would solicit sympathy and money from passers-by. Cursed Crowfoot can be identified by its succulent palmately lobed leaves and prominent clusters of green pistils in the center of its flowers. Cursed Crowfoot resembles the common Ranunculus abortivus (Small-Flowered Buttercup). The latter species has smaller flowers (about ¼" across) with triangular petals and its seedheads are less elongated and cylindrical at maturity. It also prefers drier habitats than Cursed Crowfoot.

This plant is an annual or short-lived perennial about ½–2' tall that branches frequently. The hollow stems are light to medium green, glabrous, and slightly ribbed. The basal leaves are up to 3" long and across; they have long petioles that become wider at their bases. Overall, the basal leaves are oval-cordate or kidney-shaped (reniform) in outline, but they have 3-5 shallow to deep palmate lobes, as well as blunt teeth and/or smaller secondary lobes along their margins. The alternate leaves on flowering stems are smaller in size, becoming reduced to 3 narrow lobes. A few of the upper leaves may be sessile and unlobed. Both the basal and alternate leaves are fleshy and glabrous with medium green blades and petioles.  The upper stems terminate in yellow flowers up to 1/3" (8 mm.) across. Each flower has 5 yellow petals and 5 yellowish green sepals. The petals and sepals are about the same length and shape, but the latter bends sharply downward. In the center of the flower, there is a dense cluster of green pistils that is globoid to ovoid in shape. It becomes more elongated and cylindrical as the flower matures. The cluster of pistils is surrounded by a ring of short stamens with yellow anthers. The blooming period occurs during the summer, lasting about 1-2 months. The flowers are replaced by clusters of flat smooth seeds that are kidney-shaped with short beaks. The root system is coarsely fibrous. This plant often forms colonies in wet depressions by reseeding itself.

sceleratus: harmful, poisonous

Nile region and Oases.

Europe, Mediterranean region, Southwest and Central Asia, Tropical Africa.

Ranunculus sceleratus L.:
United States (North America)
Canada (North America)
Thailand (Asia)
South Korea (Asia)
Russian Federation (Asia)
Pakistan (Asia)
Nepal (Asia)
Kazakhstan (Asia)
Japan (Asia)
India (Asia)
Bhutan (Asia)
Afghanistan (Asia)
China (Asia)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Ningxia, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xinjiang, Yunnan, Zhejiang [Afghanistan, Bhutan, N India, Japan, Kazakhstan, Korea, Nepal, N Pakistan, Russia (Siberia), Thailand; SW Asia, Europe, North America].

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Europe, C. Asia, Himalaya, N. India, Siberia, Mongolia, China, Japan, N. America.

800-1700 m

Herbs annual. Roots fibrous, subequally thick. Stems 10--75 cm, glabrous or sparsely puberulent, branched above. Basal leaves 5--13; petiole 1.2--15 cm, subglabrous or sparsely pubescent; blade 3-partite, pentagonal, reniform, or broadly ovate, or broadly ovate, 1--4 × 1.5--5 cm, papery or herbaceous, glabrous or abaxially puberulent, base broadly cordate, central lobe cuneate or rhombic, 3-lobed, lobules 1- or 2-denticulate or entire; lateral lobes obliquely broadly obovate or obliquely cuneate, unequally 2-lobed or 2-cleft to middle. Lower stem leaves similar to basal ones; upper stem leaves short petiolate, cuneate at base, 3-sect, segments oblanceolate. Compound monochasi um terminal, corymbose; bracts leaflike. Flowers 0.4--0.8 cm in diam. Pedicel 0.5--1.5 cm, glabrous or sparsely puberulent. Reeptacle puberulent or glabrous. Sepals 5, ovate-elliptic, 2--3 mm, abaxially appressed puberulent or glabrous. Petals 5, obovate, 2.2--4.5 × 1.4--2.4 mm, nectary pit without a scale, apex rounded. Stamens 10--19; anthers ellipsoid. Aggregate fruit cylindric, 3--11 × 1.5--4 mm; carpels numerous. Achene slightly bilaterally compressed, obliquely obovoid, 1--1.1 × 0.8--1 mm, glabrous, sometimes transversely 2- or 3-rugose, somewhat turgid along sutures; stigmas persistent, ca. 0.1 mm. Fl. Jan--Jul.

Stems 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. Flowers: 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 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.

Hecatonia palustris Loureiro; Ranunculus holophyllus Hance; R. oryzetorum Bunge; R. sceleratus var. sinensis H. Léveillé.

Hecatonia scelerata (Linnaeus) Fourreau

By streams or lakes, paddy fields, wet grassy places; 50--2300 m.

Primarily short-tongued bees, flies, and beetles visit the the flowers for nectar or pollen. The leaf beetles, Prasocuris ovalis and Prasocuris vittata, feed on the foliage of Ranunculus spp. (buttercups) in wetland areas (Clark et al., 2004). Buttercups are also host plants for such aphids as Rhopalosiphum nymphaeae (Waterlily Aphid), Thecabius populiconduplifolius (Folded-Leaf Poplar Aphid), and Thecabius gravicornis (Folded-Leaf Balsam Aphid); see Hottes & Frison, 1931. The seedheads are probably a minor source of food to some species of waterfowl and small rodents, although there is little specific information that is available. Because the succulent foliage contains a strong blistering agent, it is unlikely that mammalian herbivores utilize this plant as a food source to any significant extent. When livestock consume this plant, the result is severe blistering and irritation of the mouthparts and gastrointestinal tract. Photographic Location

In Great Britain and/or Ireland:
Foodplant / parasite
superficial Entylomella anamorph of Entyloma ranunculi-repentis parasitises live leaf of Ranunculus sceleratus
Other: major host/prey

Foodplant / spot causer
hypophyllous colony of Entylomella anamorph of Entylomella gibba causes spots on live leaf (radical) of Ranunculus sceleratus
Remarks: Other: uncertain

Foodplant / parasite
Erysiphe aquilegiae var. ranunculi parasitises Ranunculus sceleratus

Foodplant / open feeder
larva of Stethomostus fuliginosus grazes on leaf of Ranunculus sceleratus
Other: sole host/prey

Foodplant / parasite
aecium of Uromyces dactylidis parasitises live petiole of Ranunculus sceleratus
Remarks: season: early Spring

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 10
Specimens with Barcodes: 30
Species With Barcodes: 1

Rounded Global Status Rank: G5 - Secure

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: NNR - Unranked

The preference is full to partial sunlight, wet conditions, and soil containing clay, clay-loam, or decaying organic material. This plant grows readily in shallow water, but it will tolerate occasional droughts that cause the surface water to evaporate. The foliage is rarely bothered by insects or disease. Range & Habitat