Proc. & Trans. Roy. Soc. Canada 2(4): 30. 1884.
Aerial shoots 5-19 cm, from rhizomes, rhizomes ascending to horizontal. Basal leaves 3-15, often purplish abaxially, simple, deeply divided; petiole 3-19 cm; leaf blade widely orbiculate, 1.3-8 × 1.8- -11.5 cm, base cordate, margins entire, apex acute or acuminate, surfaces strongly villous to glabrescent; lobes 3(-5), deltate, 0.7-4 cm wide; middle lobe 70-90% of total blade length. Inflorescences 1-flowered, villous to pilose; involucral bracts 3, 1-tiered, simple, dissimilar to basal leaves, lanceolate to ovate, 0.53-1.8 × 0.27-0.95 cm, sessile, calyx-like, closely subtending flowers, bases distinct, cuneate, margins entire, apex acute, strongly villous to glabrescent. Flowers: sepals 5-12, white to pink or bluish, ovate to obovate, 6-14.6 × 2.2-5.8 mm, glabrous; petals absent; stamens 10-30. Heads of achenes spheric; pedicel 0.1-0.4 cm. Achenes: body narrowly ovoid, 3.5-4.7 × 1.3-1.9 mm, slightly winged, hispid, gradually tapering; beak indistinct. 2n=14.
Phenology: Flowering spring.
Habitat: Deciduous woods, often in calcareous soils
Elevation: 0-1200 m
Ont., Que., Ala., Ark., Conn., Ga., Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., Mo., N.H., N.Y., N.C., Ohio, Pa., S.C., Tenn., Vt., Va., W.Va., Wis.
In North America, Anemone acutiloba and A. americana are sufficiently well differentiated to enable the distinction of the two species. Some intermediates do occur but it is uncertain as to whether thes intermediates or hybrids. The fact that the two species are highly sympatric and still maintain their differences implies that they should still be recognized as distinctive species (see G.L. Stebbins 1993).
The two North American species formerly placed in Hepatica are closely allied to the Eurasian Anemone hepatica Linnaeus [=Hepatica nobilis Miller, Hepatica hepatica (Linnaeus) Karst]. Among European collections, plants approach either A. acutiloba or A. americana in leaf morphology, but some intermediates are found (J. A. Steyermark and C. S. Steyermark 1960). North American plants differ from A. hepatica in having narrower sepals, larger involucral bracts, and shorter and less pubescent scapes. Further research, including a comparative study of breeding systems, is needed to clarify the relationship between Anemone hepatica, A. acutiloba, and A. americana. Pending such work, the eastern North American hepaticas are here recognized as distinct species.
D. E. Moerman (1986) lists Hepatica acutiloba as one of the plants used medicinally by Native Americans in the treatment of abdominal pains, poor digestion, and constipation, as a wash for "twisted mouth or crossed eyes," and as a gynecological aid.