The banksia bee was originally described by German entomologist Wilhelm Ferdinand Erichson in 1842; its specific epithet is derived from the Ancient Greek halcyon "kingfisher" relating to its kingfisher blue colour.

The banksia bee has a metallic blue abdomen and yellow face markings.

Large males perch and defend Banksia inflorescences that are in high positions on the shrub where they feed; small males feed closer to the ground and patrol circuits including several inflorescences.

[5] A banksia bee nest consists of several cavities or cells within hollowed pieces of wood.

A parent bee places provisions of pollen and nectar in each cell, along with a single egg.