Anulocaulis annulatus (Coville) Standl.

Anulocaulis annulatus (Coville) Standl.. Anulocaulis annulatus is a species of flowering plant in the four o'clock family known by the common name valley ringstem. It is endemic to the Mojave Desert of California, especially in the vicinity of Death Valley. This is a perennial herb growing a number of thin, erect stems sometimes exceeding a meter in height from a thick caudex.