Here is the appropriate entry for your Lithops:
Living Stones (Lithops)
In general, the database is organized by genus. But, among other things, the parent plant architecture provides some additional flexibility. For example, there are three parent plants for the Hibiscus genus, one for Hibiscus moscheutos cultivars, one for Hibiscus syriacus cultivars, and one for everything else (I think) in the genus. On the other hand, the Asters parent plant includes several closely related genera, not just plants that are currently classified in the genus Aster.
http://garden.org/plants/brows...
