The common name for Cycas revoluta, whose seeds contain cycasin, is sago palm.
Cycas revoluta is also called the king sago palm, Japanese sago palm or sago cycad. Despite its palm-like appearance, it is not a true palm. It is a cycad, a much older lineage of seed plants that produces cones rather than flowers and belongs to the family Cycadaceae.
The species is native to southern Japan, including the Ryukyu Islands, and is widely grown as an ornamental plant. Its stiff, glossy leaves form a symmetrical crown, making it popular in gardens, containers and bonsai collections. The specific name revoluta refers to the leaflets’ strongly rolled-back edges.
The name “sago palm” reflects the plant’s historical use as a source of starch, not its botanical classification. Cycad material must be processed carefully to remove toxins, and the seeds are especially dangerous because they contain cycasin. Ingestion can cause severe gastrointestinal illness and liver damage, so the ornamental plant should not be confused with a harmless edible palm.