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Candelilla (Euphorbia antisyphilitica Zucc.) is a native plant in the desert regions of northern Mexico and the southern United States. The primary commercial use of this plant is for wax production. This study assessed the morphology, viability, and the effects of temperature in combination with chemical and mechanical scarification on the germination of candelilla seeds. Seeds were collected in four localities in northeastern Mexico. The seeds were predominantly pyriform with foveolate surfaces and brown in color; on average, the seeds measured 2.92 +/- 0.26, 1.91 +/- 0.22, and 1.50 +/- 0.41 mm in length, width, and thickness, respectively. The average weight of 100 seeds was 0.32 +/- 0.12 g. Seed viability showed a direct relationship with the color of the seed coat (thereby indicating the maturity level of the seed), with a viability of up to 86% in brown seeds, 52% in amber seeds, and 22% in gray seeds. Only brown seeds were used to assess germination after applying mechanical (sandpaper) and chemical (H2SO4) scarification, as well as two temperature (28 and 32 degrees C) treatments. The average germination rate was greater at 28 degrees C than at 32 degrees C for all treatments. The chemical scarification (at 28 degrees C) of seeds from the Lomas de Icamole locality showed the highest rate of germination (60%).