Sphecodes monilicornis (Box-headed Blood-bee)
One of three medium-sized to large Sphecodes, in which females have punctures (rather than just rugosity) behind the ocelli. S. monilicornis is easily separated from the other two (S. gibbus and S. reticulatus) by the box-shaped ('subquadrate') head when seen in top view, with the hind corners well formed. The hairs of the hind tibiae are also whitish rather than dark like the other two, and the pygidium is broader.

Males are one of a number of species with somewhat compressed and shiny antennal flagellar segments and are best confirmed using genitalia.

S. monilicornis is widespread and locally common in the southern half of Britain with records extending north to Scotland. The hosts include Halictus rubicundus, Lasioglossum calceatum, L. albipes and L. malachurum, suggesting that it might specialise on eusocial species.

BWARS account:
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