My guess would be C. fraterna, because of the absence of dark markings on the hind tibia and the absence of scutellar marginal bristles. But St. Petersburg is too far away from me to be certain.
(By the way, C. "himantopa" is incorrect spelling: it's himantopus. It's a noun in apposition, meaning 'stilt foot'. "-pa" doesn't mean anything...)
this is not fraterna because of the hairy eyes (fraterna: bare in lower part) and the almost erect mesonotal hair. How about C. nebulosa? However, without a voucher a definite identification will be impossible...
Yes? C.himantopa isn't present in region...
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