Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.
1 One- to two-year-old stems densely strigose to hispid with large, red or white trichomes; fruits densely hispid to glabrous with lenticels present, brown to greenish-brown at maturity
1 One- to two-year-old stems glabrous, sometimes finely tomentose-puberulent, but not densely strigose or hispid; fruits glabrous and without lenticels, green, purplish-green, reddish-purple, purple, orange, yellow-orange, or pinkish-orange at maturity.
..2 Pith of stems lamellate; leaf blades not variegated, only green in color without any white, yellow, or pink coloration; inflorescence a 1-7-flowered cyme; anthers dark purple to black; fruits green, purplish-green, reddish-purple, or purple at maturity
..2 Pith of stems solid or lamellate (A. kolomikta); leaf blades often variegated with some amount of white to yellow or pink coloration; inflorescence a 1-3-flowered cyme of fascicle; anthers yellow or brown; fruits orange, yellow-orange, pinkish-orange, or greenish-orange at maturity.
....3 Pith of stems lamellate and brown in color; flowers white or pink; fruits not rostrate and calyx sometimes caducous.