A worldwide community photographing and learning about wildlife
Ceratina cockerelli
This Small Carpenter Bee (less than 1 cm) was wedged inside a thistle blossom. The abdomen had a slight blue tint. I thought it was a caterpillar at first.
Thistle blossom along hiking trail in Tilden Park, Berkeley, CA.
The cosmopolitan bee genus Ceratina, often referred to as small carpenter bees, is the sole lineage of the tribe Ceratinini, and closely related to the more familiar carpenter bees. They make nests in dead wood, stems, or pith, and while many are solitary, a number are subsocial, with mothers caring for their larvae, and in a few cases where multiple females are found in a single nest, daughters or sisters may form very small, weakly eusocial colonies (where one bee forages and the other remains in the nest and lays eggs). Ceratina are commonly dark, shining, even metallic bees, with fairly sparse body hairs and a weak scopa on the hind tibia. Most species have some yellow markings, most often restricted to the face, but often elsewhere on the body. They are very commonly mistaken for "sweat bees" (family Halictidae), due to their small size, metallic coloration, and some similarity in wing venation; they can be easily separated from halictids by the mouthparts (with a long glossa) and the hindwings (with a tiny jugal lobe). A few species are exceptional among bees in that they are parthenogenetic, reproducing without males. Wikipedia