Actaea

Linnaeus

Sp. Pl. 1: 504. 175.

,

Gen. Pl. ed. 5, 222. 1754.

Common names: Baneberry necklaceweed cohosh actée
Etymology: Greek, aktea, ancient name for the elder, probably for leaf similarity
Treatment appears in FNA Volume 3.
 TaxonIllustrator 
FNA03 P33 Actaea Eranthis Nigella pg 182.jpegNigella damascena
Actaea pachypoda
Eranthis hyemalis
Actaea rubra
John Myers
John Myers
John Myers
John Myers

Herbs, perennial, from caudices ca. 1 cm thick. Leaves cauline, alternate, petiolate. Leaf-blade 1-3-ternately or pinnately compound; leaflets ovate to narrowly elliptic, unlobed to 3-lobed, margins sharply cleft, irregularly dentate. Inflorescences terminal or axillary, 25 (-more) -flowered racemes, 2-17 cm; bracts leaflike, sometimes present between leaves and inflorescence, bracteoles 1-2, at base of each pedicel, not forming involucre. Flowers bisexual, radially symmetric; sepals not persistent in fruit, 3-5, whitish green, plane, orbiculate, 2-4.5 mm; petals 4-10, distinct, cream colored, plane, spatulate to obovate, clawed, 2-4.5 mm; nectary absent; stamens 15-50; filaments filiform; staminodes absent between stamens and pistils; pistil 1, simple; ovules many per pistil; style very short or absent. Fruits berries, solitary, sessile, broadly ellipsoid to nearly globose, sides smooth; beak a wart, terminal, to 1 mm. Seeds dark-brown to reddish-brown, obconic to wedge-shaped, rugulose. x = 8.

Distribution

Temperate to cool forests throughout Northern Hemisphere

Discussion

Species ca. 8 (2 in the flora).

The two species in North America are similar to each other vegetatively and differ primarily in flower and fruit characteristics.

Selected References

None.

Key

1 Pedicel in fruit bright red, stout, (0.7–)0.9–2.2(–3) mm diam., ± as thick as axis of raceme; stigma at anthesis as broad as or broader than ovary, 1.5–2.8 mm diam. in flower and fruit; petals truncate or cleft, often antherlike at apex; berries white, very rarely red. Actaea pachypoda
1 Pedicel in fruit dull green or brown, slender, 0.3–0.7 mm diam., thinner than axis of raceme; stigma at anthesis narrower than ovary, 0.7–1.2 mm diam. in flower and fruit; petals acute or obtuse, not cleft or antherlike at apex; berries red or white. Actaea rubra
... more about "Actaea"
Bruce A. Ford +
Linnaeus +
cuneate +, truncate +  and cordate +
0 cm0 mm <br />0 m <br /> - 0.1 cm1 mm <br />0.001 m <br /> +
globose;cylindric +
Baneberry +, necklaceweed +, cohosh +  and actée +
Temperate to cool forests throughout Northern Hemisphere +
Greek, aktea, ancient name for the elder, probably for leaf similarity +
sessile +  and pedicellate +
showy +  and inconspicuous +
broadly ellipsoid;nearly globose +
axillary +  and terminal +
ovate +  and narrowly elliptic unlobed +
palmate +  and pinnate +
dentate +  and cleft +
incised;toothed;incised;toothed;entire +
cream colored +
distinct +
conspicuous +
clawed +, spatulate +  and obovate +
reduced +
0.2 cm2 mm <br />0.002 m <br /> - 0.45 cm4.5 mm <br />0.0045 m <br /> +
Sp. Pl. +  and Gen. Pl. ed. +
2 cm20 mm <br />0.02 m <br /> - 17 cm170 mm <br />0.17 m <br /> +
not arillate +  and stalked +
dark-brown +  and reddish-brown +
rugulose +
obconic +  and wedge-shaped +
whitish green +
not persistent +
distinct +
3 +  and 6 +
orbiculate +  and plane +
0.2 cm2 mm <br />0.002 m <br /> - 0.45 cm4.5 mm <br />0.0045 m <br /> +
persistent +
Ranunculaceae +
0 cm0 mm <br />0 m <br /> - 0.1 cm1 mm <br />0.001 m <br /> +
herbaceous +  and woody +