Pygmy Buttercup

Ranunculus pygmaeus var. langeana has been described as having deeply divided basal leaves and strongly elongate heads of achenes (at least 5 mm). These characteristics are not well correlated with one another, however, and the variety does not seem natural.

Stems erect or ascending from short caudices, 0.6-3.5 cm (sometimes longer in fruit), each with 1-2 flowers. Roots slender, 0.1-0.6 mm thick. Basal leaves persistent, blades reniform to transversely elliptic or semicircular, 3-parted or -divided, 0.45-0.9 × 0.6-1.3 cm, at least lateral segments again lobed, base truncate or nearly cordate, margins entire, apex rounded to obtuse. Flowers: pedicels glabrous or pubescent; receptacle glabrous; sepals 2-4 × 1.2-1.6 mm, abaxially sparsely hairy, hairs colorless; petals 5, 1.2-3.5 × 1.1-2.8 mm; nectary scale glabrous. Heads of achenes nearly globose to cylindric, 2.5-7 × 2.5-5 mm; achenes 1-1.2 × 0.8-1.1 mm, glabrous; beak subulate, straight or curved, 0.3-0.7 mm. 2 n = 16.

Greenland; Alta., B.C., Nfld., N.W.T., Que., Yukon; Alaska, Colo., Idaho, Mont., Utah, Wyo.; Europe (Spitsbergen).

Flowering summer (Jul-Sep).

Arctic and alpine meadows and slopes, usually around persistent snow patches; 0-4000m.

Ranunculus pygmaeus var. langeana Nathorst

Ranunculus pygmaeus, the pygmy buttercup or dwarf buttercup, is a species of buttercup found throughout the Arctic, as well as in the mountains of Norway and the Rocky Mountains. A few populations also exist in the Eastern Alps and Tatra Mountains.

Pygmy buttercup, Ranunculus pygmaeus

It is a small plant, prostrate-ascending, 1–5 cm tall. The stems are single-flowered, with the basal leaves numerous. The leaves are deeply cleft into 3-5 lobes. The flowers are 5–6 mm in diameter, with five pale yellow petals, and five hairy sepals. After flowering, the stems stretch considerably, reaching far above the basal leaves. It grows in snowbeds, moss carpets and other moist localities.