W. denisi Mills, 1932
– Willemia denisi Mills, 1932: 263
AK Fjellberg 1985; Skidmore 1995; Babenko & Fjellberg 2006
NT Hammer 1953; Christiansen & Bellinger 1980, 1998; Skidmore 1995
BC Battigelli & Marshall 1993; Setälä & Marshall 1994; Rusek & Marshall 1995; Setälä et al. 1995; Skidmore 1995; Addison et al. 2003, 2003a; Cannings 2010
AB Christiansen & Bellinger 1980, 1998; Skidmore 1995; Lindo 2014
QC Chagnon et al. 2001
NS Babenko, unpubl. NF Arulnayagam 1995; Puvanendran et al. 1997 General distribution: Holarctic.
Willemia sp. near denisi Mills, 1932
AK Fjellberg 1985
Remarks: This form was briefly described but not formally named by Fjellberg (1985). Recently it was also found on the other side of Bering Strait (Babenko 2017). It appears to be a true species similar to W. trisphaerae Potapov, 1994, W. fjellbergi Potapov, 1994 and W. japonica Yosii, 1970, differing mainly by the number of spherical sensilla on Ant. 4 (3, 2, 1 and 4 in W. sp. near denisi, respectively).
General distribution: Nearctic and Eastern Palaearctic.