– Proisotoma mackenziana Hammer, 1953: 50
AK Christiansen & Bellinger 1980; Skidmore 1995; Babenko & Fjellberg 2006
NT Hammer 1953; Christiansen & Bellinger 1980; Danks 1981; Babenko & Fjellberg 2006; Stebaeva et al. 2016
NU Hammer 1953a, 1955; Christiansen & Bellinger 1980; Danks 1981; Niwranski et al. 2002 as I. anglicana; Fjellberg 2003; Babenko & Fjellberg 2006
BC Battigelli & Marshall 1993; Rusek & Marshall 1995; Skidmore 1995; Cannings 2010
General distribution: Nearctic.