Ctenocolletes nicholsoni

Females are large bees, measuring 18.0 to 20.5 mm in body length.

Males are slightly smaller, with a body length of 17 to 19 mm.

Males have rich buff hair on the face and the front of the thorax, contrasting with whiter hair at the back of the head.

Females have patches of black or sooty brown hairs on the head, thorax and abdomen.

This bee is found in southern Western Australia.

It belongs to Stenotritidae, a small family of bees that occurs only in Australia.

Its genus, Ctenocolletes, is found only in Australia, and almost entirely in the west of the continent.

As a more northerly species of its genus, it may first appear in July, during the Australian winter, earlier than southern relatives.

Adults seem to be active for only about one month each year.

It appears to rely largely on Acacia pollen.

Specimens have been collected on the flowers of Acacia blakelyi and of the myrtle-family shrubs Baeckea pentagonantha and Scholtzia drummondii.

Some females keep beating their wings as they scurry over Acacia flowers.

Males are particularly fast and noisy fliers.

Adults have been found carrying tiny hitchhiking mites, which ride on the bees at a resting stage of their life cycle.