Ectemnius cephalotes misident.
Ectemnius cavifrons is one of the largest and most common species of its genus in Britain.
The map illustrates that this wasp is found throughout much of southern England, Wales and the Channel Islands (Guernsey (Luff 1895, Saunders 1902), Alderney, Sark, Jersey). It also occurs on the Isle of Man. In Scotland the species is known only from the south-east: Lothian Region (Edinburgh). The known Irish distribution is mainly concentrated along the eastern seaboard.
The species is probably under-recorded in many areas, but its basic range is nevertheless evident in the map. It is notable that recent records demonstrate a northward spread, not only of E. cavifrons but also of some other Ectemnius species.