Haworthia is a genus of succulents from South Africa related to Aloe and Gasteria. Within the genus is a group of closely related species known as the retuse haworthia. During the last 20 years a devout following for retuse haworthia has arisen as more of these diverse jewel-like plants have become available to collectors. Retuse haworthia have flattened leaves with leaf windows.  Many have intricately decorated leaves and windows that, once appreciated, make the plants irresistible.