Hardiness ratings: USDA zone 10 - 11
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- GRIN. Taxonomical details, with common names, distribution, and synonyms.
- The Plant List. Taxonomical lookup
Links for Lithops optica
- Dave's Garden PlantFiles - Profile page with horticultural basics, and member-contributed photos and comments. (zone 10-11) (1 photo)
- PlantzAfrica - Features South African plants, with photos, description, distribution and ecology, and uses. (5 photos)