[2] Calliopsis are small dark bees, often with yellow or white markings, especially in males.

Calliopsis andreniformis have green eyes, and males of the species have bright yellow faces and legs.

[3][4] Male Calliopsis fly close to the ground and, in one species, many of them evidently copulate with only a single female.

[6] Nests are built in the form of horizontal tunnels connected to waterproofed chambers containing eggs and provisions stored by the mother bee.

[7] Each female digs a solitary underground nest, usually in compacted, dense soil and close to flowering plants that serve as food sources.