Unequal cellophane bee (Colletes inaequalis)

Colletidae > Colletes > Colletes inaequalis

Unequal cellophane bee (Colletes inaequalis) carries spring on its wings. It is one of the earliest species active in the year, and can even be found when snow is still on the ground. This is a “suburban” bee, typically nesting in sunny lawns, cemeteries, and well trafficked park paths with well-draining soil. Females often sun themselves in nest entrances on cool mornings, but quickly retreat back inside if they detect a sudden movement.


C. inaequalis has a distinctively early phenology among Colletes. Active as soon as temperatures consistently rise above freezing; first bees are typically active in first week of March in New Jersey, third week of March in Massachusetts. Active until late-April/early-May, with latest records in the northern part of its range extending into June. One generation is produced per year.


Widespread throughout region, especially abundant near population centers. Seemingly absent from heavily forested regions.


Size ≈ honey bee

Females have a short malar, a sand-colored thorax, and strongly banded abdomen. 

Males resemble females but are smaller and more slender, with longer antennae and a thick brush of hair on the face.

Similar species

No other Colletes is active as early in the year as C. inaequalis.

  • C. validus has longer malar space.
  • C. thoracicus has orange thorax hairs and later phenology. Any C. inaequalis individuals that overlap with C. thoracicus will be heavily worn and have tattered wings.


Females build nests underground on south-facing slopes in sandy soils. Nests are often aggregated, with big, conspicuous tumuli dotting the earth. Nest entrances are about the width of a pencil.

Males swarm nesting sites searching for females. Male C. inaequalis are also often found swarming the tops of conifers like pitch pine (Pinus rigida) and eastern red cedar (Juniperus virginiana). Males will mate vigorously with females in groups, termed mating balls, and tumble across the ground. Males typically disappear after the first few weeks of nesting.


C. inaequalis feed on a variety of woody trees and shrubs including maple Acer, redbud Cercis, apple Malus, and willow Salix. We predictably find C. inaequalis where sand and red maples (A. rubrum) co-occur, such as at inland lakeshores or riverbanks.

Natural Enemies/Associates

C. inaequalis is parasitized by blister beetles Tricrania sanguinipennis, bee flies Bombylius spp., and anthomyiid flies Leucophora spp.

Other resources


Batra, S.W. 1980. Ecology, Behavior, Pheromones, Parasites, and Management of the Sympatric Vernal Bees Colletes inaequalis, C. thoracicus, and C. validus. J. Kans. Entomol. Soc. 53: 509-538.

Page last updated:
January 17, 2023