Herbs or subshrubs, perennial, non-twining, base woody. Leaves eglandular; stipules interpetiolar, distinct. Inflorescences of chasmogamous flowers terminal, several-flowered umbels or corymbs, or axillary single flowers; of cleistogamous flowers axillary, clusters or single flowers. Pedicels of chasmogamous flowers raised on peduncles, of cleistogamous flowers ± sessile. Flowers chasmogamous and cleistogamous [all chasmogamous]. Chasmogamous flowers 6+ mm diam., showy with visible petals, stamens, and styles; calyx glands 8 or 10 (sepals all 2-glandular or anterior eglandular); corollas bilaterally symmetric, petals carrot yellow or lemon yellow, outermost sometimes with red blotch, glabrous; stamens 5, 3 fertile, opposite anterior and posterior-lateral sepals, 2 staminodial opposite anterior-lateral sepals, (staminodial filaments shorter to somewhat longer than those of fertile stamens), [all fertile]; fertile anthers subequal, staminodial anthers rudimentary; pistil 3-carpellate, carpels nearly distinct in ovary; styles 1(–2)[–3], 1 on anterior carpel, 2d style occasionally on 1 posterior carpel, cylindric; stigmas terminal, capitate or truncate, large. Cleistogamous flowers to 1.5 mm diam., without visible petals, stamens, or styles; calyx glands 0; petals 0 or 1–2, rudimentary; stamens represented by 1–2 minute sessile anthers; pistil 2-carpellate, carpels nearly distinct in ovary; style 0 or 1, rudimentary. Fruits schizocarps, breaking into nutlets (3 in chasmogamous flowers, 2 in cleistogamous flowers); nutlets unwinged, bearing dorsal crest and often narrower lateral crest around periphery; wall thick, tough. x = 40.

Distribution

sw United States, Mexico, South America.

Discussion

Species 9 (2 in the flora).

Aspicarpa comprises three species in Mexico, with two of those in the flora area, and six species in South America south of the Amazon valley.

Selected References

None.

Lower Taxa

Aspicarpa hirtella, Aspicarpa hyssopifolia

Key

1	Chasmogamous flowers in (2–)4(–7)-flowered umbels, occasionally corymbs, terminating leafy shoots; petals carrot yellow; plants erect or decumbent with branches ascending; blades of larger leaves 6–23 mm wide, length 1.3–2.5 times width; staminodes equaling or longer than fertile stamens, surpassing sepals; nutlet with dorsal crest entire.	Aspicarpa hirtella
1	Chasmogamous flowers borne singly in axils of full-sized leaves; petals lemon yellow, outermost sometimes with red blotch; plants erect or spreading-ascending; blades of larger leaves 2–8 mm wide, length (2.2–)2.7–7(–8.3) times width; staminodes shorter than fertile stamens, ± hidden by sepals; nutlet with dorsal crest coarsely toothed.	Aspicarpa hyssopifolia