Description
''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.Mating
Male ''Calliopsis'' fly close to the ground and, in one species, many of them evidently copulate with only a single female. Mating takes place on flowers and at nest sites. ''Calliopsis'' also are univoltine, which means they only have one brood of offspring a year.Nesting
Nearly all female ''Calliopsis'' are solitary nesters, but they locate nests within aggregations with other females. Nests are built in the form of horizontal tunnels connected to waterproofed chambers containing eggs and provisions stored by the mother bee. Each female digs a solitary underground nest, usually in compacted, dense soil and close to flowering plants that serve as food sources. ''Calliopsis'' nesting aggregations can be as dense as 1,650 nests/m^2. The nest tunnels measure 7.5 mm maximum diameter and 13 mm long. ''Calliopsis'' bees build their nest the way they do to mitigate competition between males. Their nest is built for waterproof hazards to keep the soil dry until the ground evaporates. Although reported in a few other bee groups, ''Calliopsis'' are unusual in that some species' nests can survive complete submersion: ''Calliopsis pugionis'' emerged from nests that had been underwater for at least 3 months.Species
These 88 species belong to the genus ''Calliopsis''.References
{{Taxonbar, from=Q14491786 Andrenidae Bee genera Taxa named by Frederick Smith (entomologist)