Photo: Arnstein Staverløkk / NINA / CC BY 3.0
Osmia leaiana
Orange-vented Mason Bee
A small mason bee (7–9 mm) with a black body and bright orange ventral scopa. Females have dense brownish hair on the thorax; males are metallic green with ginger hairs. It is oligolectic on Asteraceae, especially thistles and knapweeds. It nests in pre-existing cavities in dead wood, fence posts, and bee hotels. In Switzerland it is widespread in gardens, meadows, and woodland edges, flying from May to August. Swiss Red List: Least Concern (LC).
Species Facts
- Size
- 7–9 mm
- Flight Period
- May to August
- Nesting
- Cavities
- Specialization
- Asteraceae
- Abundance
- Uncommon
- Family
- Megachilidae
External Sources
This data has been cross-referenced with national sources:
Data Source & Copyright
| Category | Source / Author | License |
|---|---|---|
| Photo | Arnstein Staverløkk / NINA | CC BY 3.0 |
| Taxonomy & Distribution | InfoFauna Switzerland | Public data |
| Global Distribution | GBIF | CC BY 4.0 |
Data Quality
High Quality Last audit: 2026-05-22
Completeness: 100%
✓Photo exists✓Traits consistent✓Description quality✓Red List referenced✓Attribution verified
Confidence: 67%
IdentifiabilityMediumImage confidenceMediumImage qualityHighTrait coherenceHigh
