When does a female cuckoo bee typically lay her egg in a host cell?

Answer

After the host female has provisioned the cell with nectar and pollen but before it is sealed.

The cleptoparasite waits for the host female to leave after provisioning a cell with nectar and pollen, slips inside, lays a single egg into the prepared food mass, and then quickly departs before the host returns and seals the cell.

When does a female cuckoo bee typically lay her egg in a host cell?
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