HymenopteraMegachilidae

Leafcutter Bee

Megachile willughbiella

This record describes Megachile willughbiella (species). Recorded family: Megachilidae. Recorded order: Hymenoptera.

Identification and Appearance

Leafcutter Bee - Megachile willughbiella

Length 12 to 18 mm. A large leafcutter bee, the males of which have distinctive white flattened front tarsi. Females of this genus can be difficult to identify, even under a microscope. It is the commonest leafcutter bee and the species most likely to be encountered in gardens where it readily uses bee hotels. See our ID Aid below below for identifying males. Where a photo is surrounded by a red box it means that it is representative of the species but may not be the actual species described. Most solitary bees and wasps are difficult to identify, and can rarely be identified from photos taken in the field. All red-rated records should include a photo, or set of photos, showing the key characters, which may require the specimen. Please include a face shot, side, top and wings. Note whether male or female, explain how the specimen met the key characters and the key used. We will accept records identified by a recognised local or national expert, or that have been identified via the BWARS’ Facebook noting the name of the person/organisation identifying the record (e.g. ‘Stuart Roberts, BWARS Facebook’). Often found in gardens. It nests in sunny, sheltered locations in crevices in dead wood or in the ground, sometimes using the soil in flower pots. Female Megachile bees construct nests of larval cells from leaves and provision each cell with a mixture of pollen and nectar for the young. The larva feed on this food store before overwintering and emerging the following summer.

Classification

Kingdom
Animalia
Phylum
Arthropoda
Class
Insecta
Genus
Megachile

Imported taxonomy record. Source availability varies; see the source references and editorial policy below.

Habitat and Range

Habitat

Often found in gardens. It nests in sunny, sheltered locations in crevices in dead wood or in the ground, sometimes using the soil in flower pots.

Seasonal Activity

June to August.

Diet and Behavior

Life History

Female

Additional species information

Recorded status

Common.

About Flies: the wider group

Order-level background for Hymenoptera, the group containing Megachile willughbiella. Species-specific details appear above.

Group overview

Hymenoptera includes over 150,000 described species of ants, bees, wasps, and sawflies. Earth harbors approximately 20 quadrillion (20×10^15) ants, with a combined biomass of ~12 megatons of dry carbon - exceeding the combined biomass of all wild birds and mammals (PNAS, 2022).

Ecological role of the group

About 35% of the world's food crops depend on animal pollinators. The chocolate industry, valued at over $100 billion, depends on pollinating flies and midges. Ants are the dominant soil engineers in most terrestrial ecosystems, turning more soil than earthworms in many habitats.

Economic and practical significance of the group

Pollinators contribute $235-577 billion worth of annual global food production (FAO). In the U.S., bee pollination alone benefits crops valued at $18 billion annually, and honey bees are responsible for $5.4 billion in agricultural productivity. Between April 2023-2024, 55.1% of managed honey bee colonies were lost. The U.S. bee population dropped from 5 million to 2.5 million.

Recorded sources for this group: FAO, USDA, EPA, PNAS (2022), US Fish & Wildlife Service. Imported estimates may describe particular regions or reporting periods.

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Frequently Asked Questions About Leafcutter Bee

What is Leafcutter Bee?

Leafcutter Bee (Megachile willughbiella) is a species in the family Megachilidae, within the order Hymenoptera.

How big is Leafcutter Bee?

12 to 18 mm. A large leafcutter bee, the males of which have distinctive white flattened front tarsi. Females of this genus can be difficult to identify, even under a microscope. It is the commonest leafcutter bee and the species most likely to be encountered in gardens where it readily uses bee hotels.

Where is Leafcutter Bee found?

Habitat: Often found in gardens. It nests in sunny, sheltered locations in crevices in dead wood or in the ground, sometimes using the soil in flower pots.

When is Leafcutter Bee active?

Leafcutter Bee: seasonal activity - June to August..

What is the life cycle of a Leafcutter Bee?

Female