Anthidium

Anthidium February 2008-1

Anthidium is a genus of bees belonging to the family Megachilidae, commonly known as carder or wool bees. The genus is diverse and widespread, with species found across the globe, particularly in temperate regions. Anthidium bees are solitary, with females constructing nests from plant fibers. These bees are notable for their unique behavior of collecting plant fibers to build their nests, a trait that has earned them the common name of carder bees.

Description

Anthidium bees vary in size and appearance, but they typically have robust bodies covered with dense hairs. The coloration can range from predominantly black to patterns of yellow and black. Males are often larger than females, a trait unusual among bees, and can be distinguished by their more aggressive behavior and territoriality.

Behavior

Anthidium bees are solitary, with each female constructing her own nest. Unlike social bees, they do not form colonies. Females collect hairs from plants, which they use to line their nest cavities. These cavities can be found in various locations, such as in the ground, in wood, or even in pre-existing holes in structures. The collected plant fibers are meticulously carded and shaped to form the nest.

Males are known for their territorial behavior, often guarding territories where females are likely to visit for nesting materials or flowers for nectar. They can be aggressive towards other males and sometimes towards larger insects or even humans who enter their territory.

Reproduction

In Anthidium, mating occurs outside the nest. After mating, the female lays her eggs in the nest she has constructed and provisioned with a supply of pollen and nectar for the larvae to consume upon hatching. The female then seals the nest, and the adult bees do not return. The larvae develop within the safety of the nest, emerging as adults ready to continue the cycle.

Ecology

Anthidium bees play a significant role in the pollination of various plant species. While foraging for nectar and pollen, they inadvertently transfer pollen between flowers, facilitating plant reproduction. They are particularly attracted to flowers in the families Lamiaceae (such as lavender and sage) and Fabaceae (such as beans and peas).

Conservation

While many Anthidium species are not currently considered endangered, they face threats from habitat loss, pesticide use, and climate change. Conservation efforts are important to ensure the survival of these beneficial pollinators.

See Also

• Bee
• Pollination
• Solitary bee
• Megachilidae