Sphecodes monilicornis (Box-headed Blood Bee)
One of three medium-sized to large Sphecodes in which females have punctures (rather than just rugosity) at the back of the head behind the ocelli. S. monilicornis is easily separated from the other two (S. gibbus and S. reticulatus), indeed all other British Sphecodes, 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 (dark in 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 the Inverness area. Females fly from late March into autumn with males appearing in July. Hosts include Halictus rubicundus, Lasioglossum calceatum, L. albipes and L. malachurum, suggesting that it might specialise on eusocial species.

BWARS account:
www.bwars.com/bee/halictidae/sphecodes-monilicornis
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