Osmia spinulosa (Kirby, 1802)

Müller, Andreas, 2018, Palaearctic Osmia bees of the subgenus Hoplosmia (Megachilidae, Osmiini): biology, taxonomy and key to species, Zootaxa 4415 (2), pp. 297-329 : 301

Osmia spinulosa species group

The members of this species group are characterized by the morphology of the mesosoma and the nesting site. In contrast to all other O. ( Hoplosmia ) species, the scutellum hides the metanotum when seen from above and its posterior margin reaches the same level as the metanotum or even overhangs it when seen in profile. All species for which the nesting biology is known nest in empty snail shells, which are never selected as nesting sites by the members of the other two species groups.