| Family | EUPHORBIACEAE |
| Genus species | Euphorbia chaetocalyx (Boiss.) Tidestr. |
| Bibliography | Proc. Biol. Soc. Washington 48: 40 (1935) |
| Native Range | Arizona to Texas and ne. Mexico |
| Primary Biome | Subtropical |
| Habitat | rocky slopes |
| Altitude | 600-2500m |
| Description | woody taproot, leaves opposite, ovate to lanceolate, entire, acute, glabrous, cyathium single. involucre campanulate or crateriform, glabrous |
| Size | 5-20cm |
| Color | yellow-red |
| Bloom | spring, summer |
| Ca | |
| Type | perennial |
| Cultivation | sunny, dry, rock crevices, protection against winter wet alpine house, poor, drained soil, sun |
| Propagation | seed in winter, germ. 1-3 months, 18-21°C cuttings in late spring and late summer |
| Synonyms | Chamaesyce chaetocalyx (Boiss.) Wooton & Standl. Chamaesyce fendleri var. chaetocalyx (Boiss.) Shinners Euphorbia fendleri var. chaetocalyx Boiss. |
| Territory | 7 Northern America 76 Southwestern U.S.A. (ARI Arizona) 77 South-Central U.S.A. (NWM New Mexico, TEX Texas) 79 Mexico (MXE Mexico Northeast) |