Small Carpenter Bees

Ceratina

Classification

Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Order: Hymenoptera
Family: Apidae
Subfamily: Xylocopinae
Genus: Ceratina

Pronunciation

How to pronounce Ceratina: //ˌsɛrəˈtaɪnə//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Ceratina obtusicauda by the Smithsonian. Used under a CC0 license.

Ceratina hurdi by the Smithsonian. Used under a CC0 license.

Ceratina amabilis by the Smithsonian. Used under a CC0 license.

Ceratina (Pithitis) binghami by the Smithsonian. Used under a CC0 license.

Ceratina triangulifera by the Smithsonian. Used under a CC0 license.

Summary

Ceratina is a genus of small carpenter bees known for their solitary and subsocial nesting behaviors. They are distinctive for their metal-like appearance and small size. Some species display interesting social behaviors, including biparental care and parthenogenetic reproduction.

Physical Characteristics

Ceratina are commonly dark, shining, even metallic bees with fairly sparse body hairs and a weak scopa on the hind tibia. Most species feature yellow markings, generally limited to the face but frequently appearing elsewhere on the body. They are relatively small, generally under 8 mm in length.

Identification Tips

Ceratina can be identified by their small size (under 8 mm), contrasting with the larger Xylocopa (20 mm or larger). Another identification tip is that the second submarginal cell is about as high as wide basally in Ceratina, while in Xylocopa, it is about half as high as wide.

Habitat

Ceratina excavate nests in the pith of dead wood, stems, or plant twigs, primarily in broken or burned plants. They typically nest in sumac and elder stems.

Distribution

Ceratina is a cosmopolitan genus with over 300 species in 23 subgenera worldwide.

Diet

Adults visit a variety of flowers, particularly enjoying raspberry and goldenrod blooms.

Life Cycle

Females overwinter as adults in partially or completely excavated stems, modifying these resting sites into brood nests in spring. Some species exhibit bivoltine nesting phenology.

Reproduction

A few species of Ceratina are parthenogenetic, reproducing without males. Social nesting is observed in some species, whereas others remain solitary.

Evolution

The genus Ceratina is the sole lineage of the tribe Ceratinini, which indicates a unique evolutionary path distinct from other carpenter bees.

Similar Taxa

Misconceptions

Ceratina are often mistaken for sweat bees (family Halictidae) due to their small size and metallic coloration.