What is "sarcostemma"

Sarcostemma is a genus of flowering plants in the dogbane family, Apocynaceae, first described as a genus in 1810. The name is derived from the Greek words σαρκὸς (sarkos), meaning "flesh," and στέμμα (stemma), meaning "garland". Members of the genus are known generally as climbing milkweeds or caustic bushes. They are found across Africa and tropical Asia, in Australia, and in parts of North America. These plants are perennial flowering shrubs with trailing vines or lianas. They are often adapted to heat and/or desert conditions. Some have few or no leaves and photosynthesize in the tissues of the green stems. The soft stems are filled with a milky white latex that is poisonous and caustic in some species. The flowers have a ring of thick tissue at the base which extends into hollow spherical appendages within the flower corolla.