Osmia caerulescens

• Scientific name: Osmia caerulescens
• Common name: blue mason bee
• Dimension: 7-9 mm
• Habitat: woodland margins, clearings, dry meadows, traditional orchards, uncultivated vineyards and often also in urban areas
• Behavior: solitary
• Collective behavior: polylectic
• Nest: in various above-ground cavities, such as xylophagous insect galleries in dead wood and cracks in walls
• Parasitized by: Stelis ornatula
• Red list of bees in Switzerland: not endangered

Interesting Facts:

The metallic green color clearly distinguishes the males of blue mason bee from the females, which have iridescent blue reflections.