Ranunculus sabinei R. Br. Synonyms: pygmaeus ssp. sabinei (R. Br.) Hultén pro parte

Global Distribution: Northern Asia from Siberia through Russian Far East, Alaska, and Canadian Arctic to Greenland.

Alaska Distribution: Arctic Tundra.

Ecoregions Occupied: Beaufort Coastal Plain (Point Barrow).

Conservation Status: S1 G4; BLM Watch.

Description24, 25, 160

Fruiting heads globose 4 to 7 mm long, to short-cylindrical; pilose with colorless beaks of achenes 0.4 to hairs 0.6 mm long

Petals nearly the same length as sepals, 5 to 8 mm long, yellow Basal broadly obovate to kidney-shaped, 3- to 5-lobed

1 cm

Illustration by Matthew L. Carlson 259

Ranunculus sabinei

General: Perennial herb from simple, non-fibrous caudex and slender roots, tufted; stems erect or decumbent, 1 to 12 cm tall, sparsely pilose.

Leaves: Basal petioles 26 to 32 mm long; basal leaves somewhat fleshy, broadly obovate to kidney-shaped, 3- to 5-lobed, 9 to 30 mm long, 8 to 34 mm wide; segments undivided, entire with rounded or rounded-obtuse apexes; stem leaves 1 to 2, reduced, more deeply cleft.

Flowers: 1 to 3; pedicels pilose; sepals 4 to 7 mm long, 2 to 3 mm wide, purple-tinged, pilose with colorless hairs; 5 per , yellow, 5 to 8 mm long, 3 to 4 mm wide.

Fruits: Fruiting heads globose to short-cylindrical, 6 to 9 mm tall, 4 mm wide; achenes 1.2 to 1.4 mm long, glabrous; beaks straight or curved 0.4 to 0.6 mm long.

1 cm

ALA 38479

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Ranunculus sabinei

Ecology

Elevation: Known from near sea level.

Landform: Tundra slopes, hummocks, estuary banks; all occurrences near coast.

Soil Type: Sand, gravel.

Moisture regime: Moist.

Slope: Flat to gently sloped.

Aspect: No particular aspect.

Vegetation type: Often associated with turf.168

Longevity: Perennial; short-lived.63

Phenology: Flowering June through mid-July; fruiting early July through August.

Population estimate: There are six known occurrences in Alaska, but it is unknown if all six are still extant; at least two populations are locally uncommon.

Reproductive biology: Probably fly-pollinated.115

Similar Species24, 25, 160

The table below shows the morphological features that distinguish Ranunculus sabinei from other low-growing Ranunculus with lobed leaves that occur in arctic Alaska, often in similar habitats.

Species Basal Leaves Sepals Petals Achene Beaks 3- to 5-lobed; Pilose with Petals nearly same Ranunculus 0.4 to 0.6 mm lobes undivided, colorless as sepals, 5 to 8 sabinei long entire hairs mm long Sparsely Deeply palmately pubescent Petals shorter than Ranunculus 0.3 to 0.7 mm divided into 3- to with sepals, 1.2 to 3.5 pygmaeus long 5-lobes colorless mm long hairs Sparsely 3-lobed, lobes Petals longer than Ranunculus pubescent 0.6 to 1.8 mm again once sepals, 6 to 12 mm eschscholtzii with pale long divided long yellow hairs Deeply 3-lobed, Densely Petals longer than Ranunculus lateral lobes cleft pubescent 1 to 2 mm sepals, 8 to 11 mm nivalis again halfway to with stiff, long long base brown hairs Round-toothed or Densely shallowly 3- Petals longer than Ranunculus pubescent 0.8 to 1.4 mm lobed with sepals, 8 to 12 mm sulphureus with stiff, long round-toothed long brown hairs lateral lobes Petals nearly same Ranunculus 3-lobed, lobes Glabrous or 0.4 to 0.8 mm as sepals, 3 to 6 grayi again 3-lobed pubescent long mm long

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Ranunculus sabinei

© Forrest Baldwin 1994

© Forrest Baldwin 1994

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