Crossosoma californicum, known by the common name California rockflower, is one of only a few species in the flowering plant family Crossosomataceae.
Crossosoma californicum is native to San Clemente and Santa Catalina Islands, two of the Channel Islands of California, as well as Guadalupe Island off the coast of Baja California.
It is also known from one location on the mainland California coast at the Portuguese Bend Nature Preserve, on the Palos Verdes Peninsula of Los Angeles County.[1]
Crossosoma californicum is a shrub or small tree sprawling to a maximum height of 5m (16feet). The stem is intricately divided into many thorn-tipped branches lined with veiny, pale green, oval-shaped to rounded leaves up to 9 centimeters long.
The species produces solitary flowers with round white petals, each one to 1.5 centimeters long. At the center are numerous of stamens and 1-5 free carpels