Acalypha neomexicana Muell.-Arg.
Family: Euphorbiaceae
New Mexico Copperleaf,  more...
Acalypha neomexicana image

Plant: annual herb; to 35 cm tall; stems simple and erect or branched and ascending, with dense to sparse short recurved hairs

Leaves: ovate, 1.5-5 cm long, 0.75-2.5 cm wide, sparsely strigose and ciliate; apex acute; base rounded; margin serrate on the distal 4/5, entire below; petioles about 0.5 to as long as the blade, with pubescence like the stems

INFLORESCENCE: SPIKES of two kinds: staminate spikes axillary, 1-6 mm long on pedicels 1-3 mm long; pistillate spikes terminal (sometimes on short lateral branches and so appearing axillary), 2-5(-7) cm long, moderately compact, often appearing widest at the apex; bracts subtending pistillate flowers often purplish, 2-3 mm long in flower and 12-15 mm long in fruit, with 7-13 acute teeth of which the middle tooth is much longer than the others, hispid on the nerves, ciliate and glandular

Flowers: ALLOMORPHIC FLOWERS sessile; ovary bilobed, covered with small bumps, hispid

Fruit: ca. 1.5 mm long, ca. 2 mm wide, hispid toward the apex. SEEDS 1.2-1.5 mm long, gray or brown, often mottled, finely pitted

Misc: Moist or shaded areas, foothills and mts; 650-2450 m (2100-8000 ft); Aug-Oct

References: Kearney & Peebles; Arizona Flora. McDougall; Seed plants of Northern AZ.

REFERENCES: Levin, Geoffrey A. Euphorbiaceae. Part 1. Acalypha and Cnidoscolus. J. Ariz. - Nev. Acad. Sci. 29(1): 18.

Wiggins 1964, USDA 2015, VPAP (Levin 1995), MacDougall 1973

Duration: Annual

Nativity: Native

Lifeform: Forb/Herb

General: Annual herbs, 10-40 cm tall, from a short taproot; stems erect; smaller plants unbranched and larger plants with many ascending branches; herbage often tinged with red, covered with dense to sparse short recurved hairs; sap not milky.

Leaves: Alternate along the stems and branches, on petioles 1-3 cm long; blades ovate, 1-5 cm long and 1-3 cm wide, with a rounded base and pointed tip, the edges serrate except at the leaf base; surfaces sparsely strigose, especially on veins and leaf margins.

Flowers: Separate male and female flowers on the same plant; pistillate (female) flowers in terminal and axillary spikes, 1-5 cm long, with each flower or pair of flowers subended by a bract; bracts ovate, 2-3 mm long in flower and 5-11 mm long in fruit, often purple-tinged and glandular, with toothed edges, the central tooth much longer than the other teeth, hairy on the edges and veins; staminate (male) flowers tiny, in small spikes inserted at the base of the pistillate spikes.

Fruits: Capsules distinctly 3-lobed, depressed-globose, 3-4 mm wide, sparsely hairy; seeds 1 mm long, gray or brown, often mottled and finely pitted.

Ecology: Found in moist areas and rocky soils, from 2,500-7,500 ft (762-2286 m); flowers August-November.

Distribution: AZ, NM, sw TX; south to c MEX.

Notes: Distinguished by being an erect annual of varying size, depending on moisture and habitat; the serrate leaves have pronounced veins; and the inflorescence is made of leaves (larger and petiolate) and floral bracts resembling leaves (smaller and sessile) densely stacked one above the other. The floral bracts have palmate veins and appear to cup each flower; later they cup each 3-lobed seed pod. The common name is New Mexico Copperleaf because the leaves and bracts are often red-tinted, especially when growing in full sun.

Ethnobotany: Unknown

Etymology: Acalypha is from Greek akalephes for nettle, while neomexicana refers to New Mexico.

Synonyms: None

Editor: SBuckley 2010, FSCoburn 2015, AHazelton 2017