Dark thorax with dark hairs and bright orange-red abdomen (more strongly contrasting than Osmia bicornis). Long  inwardly-curved facial horns on the head below the antennae (longer than in Osmia bicornis). Males have a large patch of long white hairs on the face. 

Osmia bicornis

Detailed photos show key identification features required.

In a variety of habitats including urban places, and really loves bee hotels. This species can be an important pollinator of fruit trees. 

Adults fly from March to late May, with males appearing before females. Generally flies earlier than Osmia bicornis. 

First recorded in London in 2014, now expanding its range.

First record 2025. 

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