A key is available in Perkins (1925). Else & Edwards (in press) will also have a key. Formerly included in Chalicodoma, now treated as a subgenus of Megachile.
There are no recent records of M. ericetorum in Britain. There are two specimens collected by Smith in 1844 from Weybridge, Surrey and there are a few other unsubstantiated records as well from around this time from Bristol, Sandwich and Southampton. The Weybridge specimens remain the only authenticated records for this species in Britain.
Globally, M. ericetorum is found from Belgium, France, Spain across to Romania, Italy and Greece. Further afield it has been recorded in Turkey and China and recently (2010) a single female was collected from Canada though it is not yet thought to be established there.