Déposé par Michael, le 11.08.2021
Hi there
I saw this blue butterfly today at around 600 metres altitude near Blumenstein in Canton Bern near to the Gruber river. It was in grassy areas next to the river and next to a wood.
I thought it was a Mazarine blue (semiargus) but it seemed a bit smaller and when i took the photo i could see it had 2 spots on the basal area of the wing - which makes it less likely to be semiargus ?
Could this be cupido osiris ?
Many thanks
Michael
Dear Michael,
The two spots you mention indeed exclude semiargus.
One definite feature here is the short tail of the hindwing pointing to Cupido alcetas. In some cases it is a true tail, in other (and most cases, like here) only a kink of the wing edge is present. In osiris the edge is completely smoothly rounded, without any hint of a kink.
Best regards,
Vincent
