Stylosanthes biflora

The genus name “Stylosanthes” comes from the Greek words “stylo” and “anthos,” which collectively mean “style flower.”  This refers to the stalk-like, hollow calyx tube that surrounds the pistil of the flower, which is also why this plant is called pencil flower.  The species name “biflora” means “two-flowered.”  Despite this name, the flowers are often solitary.