|Small Carpenter Bee – Ceratina sp.|
Subfamily Xylocopinae – Carpenter Bees
Bees & Wasps Index | Bees & Wasps Main | Stinging Hymenoptera
Live adult carpenter bees photographed in the wild at DuPage County, Illinois, USA.
Carpenter bees are black, bluish green, or blue, and often have yellow or white markings on the clypeus, pronotal lobes, and legs. There are two genera within the family, Ceratina (small carpenter bees), and Xylocopa, large carpenter bees. Bees in Ceratina excavate nests with their mandibles in the pith of broken or burned plant twigs and stems, but large Xylocopans can damage wooden human structures. Both male and female carpenter bees overwinter as adults within their old nest tunnels. Adults emerge in the spring (April and early May) and mate.
In the spring, this resting place (hibernaculum) is modified into a brood nest by further excavation. The female collects pollen and nectar, places this mixture (called beebread) inside the excavation within the plant stem, lays an egg on the provision, and then caps off the cell with chewed plant material. Several cells are constructed end to end in each plant stem, the number depending upon the depth to which the nest was excavated. It is thought the female bee remains with the nest, guarding it until all her progeny have emerged.
Large carpenter bees can become pests when they bore their brood tunnels into woodwork, into wood trim near eaves and gables of homes, facia boards, porch ceilings, outdoor wooden furniture, decks, railings, fence posts, and shingles; small carpenter bees generally eschew human habitation for plant material. –USDA Carpenter Bees
The "pupil" in an insect's compound eye is an evolutionary adaptation which makes it appear as if the eyes are following you – it's an optical illusion formed by the individual cells themselves; when you are looking directly into the cell, you can see the darker substrate at the bottom. Those cells, being pointed directly at you (or the camera, in this case) are the ones that most clearly convey your image to the bee's brain.
Hymenoptera (Latin for membrane wing) is a vast assemblage of insects second only to Coleoptera (beetles) in the number of described species. Hymenoptera number some 115,000 species – of which 18,000 live in North America. Hymenopterans inhabit a wide variety of habitats, and show an incredible diversity in size, behavior, structure and color.
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