About Euphorbia cuphosperma (Engelm.) Boiss.
Euphorbia cuphosperma (Engelm.) Boiss. is an annual herbaceous plant with a taproot. It grows up to 20 centimeters (about 8 inches) tall, and the entire plant is hairy to varying degrees. Its leaf blades can differ greatly in shape, and leaf margins may be either toothed or smooth. Whorls of green, leaf-like bracts located below the flowers often fan out, partially surrounding the plant's flowers and fruits.
Based on the map of documented observations on iNaturalist, Euphorbia cuphosperma grows in the southwestern U.S. states of Arizona and New Mexico. Surprisingly, the species has not been documented in northwestern Mexico; most of its population is found in mountainous central and northeastern Mexico, and its range extends south into Oaxaca. There may also be an unconfirmed report of this species from highland Guatemala.
In the United States, Euphorbia cuphosperma inhabits open mountain and canyon forests, pinyon-juniper forests, montane grasslands, stream beds, and disturbed habitats, at elevations between 800 and 2000 meters (about 2600 to 6600 feet). In the highland Valley of Mexico, the species has been recorded growing in scrub and grasslands in semi-arid areas, particularly in disturbed and waste ground, at elevations between 2250 and 2700 meters (about 8200 to 8850 feet). In this region, the species is apparently never very common.
