Anulocaulis annulatus (Coville) Standl.

Nomenclature

Anulocaulis annulatus, with the scientific name Anulocaulis annulatus (Coville) Standl., is a species of flowering plant in the four o'clock family, commonly known by the common name valley ringstem.

Distribution

It is endemic to the Mojave Desert of California, and occurs most commonly in areas around Death Valley.

Growth Form

This plant is a perennial herb that grows multiple thin, erect stems from a thick caudex; the stems can sometimes grow taller than one meter.

Stem Characteristics

The smooth stems have darkened internodes at intervals, which are glandular and sticky.

Leaf Arrangement

Most of the plant's leaves grow at its base.

Leaf Structure

Each leaf has a short petiole and a thick, bumpy blade that can reach up to 10 centimeters wide.

Leaf Surface

The leaf surface is covered in large, stiff hairs that have glandular bases.

Inflorescence

A branching inflorescence holds clusters of very hairy, tubular flowers.

Flower Characteristics

Each flower is just under one centimeter long, with a greenish throat and a striped pink face.

Fruit Characteristics

The fruit is a small, hard structure that is approximately half a centimeter long.