I. tricolor (Packard, 1873)
– Isotoma tricolor Packard, 1873: 34
NU Fjellberg 1986; Babenko 1993, 1994a; Babenko & Bulavintsev 1993, 1997; Niwranski et al. 2002; Chernov 2004
ON Christiansen & Bellinger 1980, 1998; Skidmore 1995
Remarks: Records of I. tricolor and I. stuxbergi from northern Canada very likely belong to a single morphological form (see remarks on I. palustris).
General distribution: Nearctic.
Unplaceable records of Isotomurus sp.:
NU Hogg & Hebert 2004, cf. palustroides / stuxbergi
MB McClure 1943 as I. retardatus Folsom, 1937 (considered “problematic” by Christiansen & Bellinger 1998, p. 754)
NF Arulnayagam 1995