Members of Zeopoecilus have not been found with any Megadromus species except on small Stephens Island (see Megadromus bucolicus) and, like Plocamostethus planiusculus, do not cross the Great Alpine fault. Z. calcaratus lies in the Marlborough Sounds and west almost to the Richmond Range and Nelson Lakes National Park. The distribution detail along the 50 km boundary between it and Zeopoecilus putus in the eastern portions of Nelson is still unknown.