Wiggins 1964, Jepson 1993, Kearney and Peebles 1969
Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Erect to strongly ascending annual 5-60 cm tall with mostly glabrous but sometimes sparsely pilose herbage, stems simple to moderately branched at or near base. Leaves: Lanceolate to oblong, 4-20 mm, sometimes with a red blotch at center, margins evenly serrated, paler beneath than above. Flowers: Cyathia 0.4-.9 mm wide, solitary or in few-flowered cyme, peduncle 0.5-2 mm long, involucral glands 0.2-0.4 mm wide oval pink to maroon, appendages 0.3-0.6 mm wide, broader than long, white to pink, darkening with age; staminate flowers 4-15 per cyathium. Fruits: Strongly 3-lobed capsule, 1.6-2.1 mm long, with obtuse to rounded angles, glabrous. Ecology: Found on valley flowers, grassy slopes, washes, and rocky hillsides from 1,000-6,000 ft (305-1829 m); flowers throughout year under favorable moisture. Distribution: Widely distributed; Africa, Europe, e Asia, Australia; much of s N. Amer. and s US from UT and AZ east to MD; south through FL, Greater Antilles, MEX, C. Amer. and S. Amer. Notes: A highly variable plant in size, habit and shapes of leaves. Distinguished for the most part by being a mostly hairless annual, sometimes with sparse hairs; serrate leaves many longer than 15 mm; a hairless ovary larger than most species 2-2.5 mm long; and seeds with ridges. Could be confused with E. serpillifolia except it is more erect and larger in general, has more elongated leaves and ridges on seeds. Ethnobotany: Unknown for this species, other species in genera have medicinal use. Etymology: Euphorbia is named for Euphorbus, Greek physician of Juba II, King of Mauretania, hyssopifolia means having leaves like Hyssop. Synonyms: Chamaesyce brasiliensis, Euphorbia brasiliensis, Euphorbia hyssopifolia Editor: SBuckley 2010, FSCoburn 2015