O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
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Distribution and Systematics. — The fringed myotis is found in the western United States, 
western Canada, and Mexico (Fig. 32). In the United States, the distribution includes all or parts of 
the following states: Arizona, California, Colorado, Idaho, Nebraska, Nevada, New Mexico, Ore¬ 
gon, South Dakota, Texas, Utah, Washington, and Wyoming (O’Farrell and Studier, 1980). 
There have been no major changes to the nomenclature of this species since the original 
description by Miller (1897). Four subspecies are recognized (Miller, 1897; Miller and Allen, 1928; 
Jones and Genoways, 1967; Manning and Jones, 1988). M. thysanodes thysanodes occurs in the 
western United States in suitable habitat from western Texas through New Mexico, Arizona, Utah, 
Colorado, southern Wyoming, Idaho, Nevada, California, Oregon, and Washington; M. thysanodes 
aztecus is found in south central Mexico (Oaxaca); M. thysanodes pahasapensis is found in south¬ 
western South Dakota, northwestern Nebraska, and eastern Wyoming; and M. thysanodes vespert- 
inus is reported to occur in southwestern Washington, western Oregon, and northwestern Califor¬ 
nia. The validity of these subspecies designations has not been investigated with modem genetic 
approaches. Other English common names include fringed bat and fringe-tailed myotis. The spe¬ 
cific epithet stems from the Greek thysanos, meaning “fringe” or “tassel”, and odes, meaning 
“resemblance”. 
Analyses and discussion of molecular genetic relationships of the fringed myotis to other 
species of myotis and possible genetic-based groupings within M. thysanodes have been provided 
by recent authors, including Dewey (2006), Stadlemann et al. (2007), Carstens and Dewey (2010), 
and Vonhof et al. (2015). These studies suggest close evolutionary relationships of fringed myotis 
with the long-eared myotis, Keen’s myotis, and one subspecies of the little brown myotis. Rela¬ 
tionships among some of these species based on morphology, allozyme variation, and other traits 
also have been hypothesized (for example, Reduker et al., 1983). 
Habitats and Relative Abundance.— Early mammalogists referred to habitat used by 
fringed myotis as the Upper Sonoran or Transition life zones, from about 1,200 meters up to about 
2,500 meters in elevation (Grinnell, 1918; Bailey, 1931). These ranges in habitat remain valid as 
generalizations based on additional studies, but elevations as high as 2,850 meters in spruce forest 
and as low as sea level have been since recorded (for example, Orr, 1956; Davis and Barbour, 1970; 
Hayes, 2011). Relative abundances of this species in bat community surveys vary among regions 
and habitats range-wide. This species often ranks from low to intermediate in relative abundance 
in these surveys. 
Pacific Northwest and Northern Rocky Mountains: Fringed myotis were low in relative 
abundance in most surveys in the Pacific Northwest and northern Rockies. In northeastern Oregon, 
they were found to be uncommon or difficult to collect across a variety of habitat types (Whitaker 
et al., 1981). Captures of night-roosting bats at five bridges in western hemlock forest in the 
Willamette National Forest of Oregon included eight species and 412 individuals, but no bats of 
this species (Perimeter, 1996). They were very rarely captured in forests of multiple types in north¬ 
ern Idaho (two bats captured for fecal analysis among 187 individuals of eight species taken; Lacki 
et al., 2007). These bats ranked third in relative abundance (137 captures of 1,057 individuals of 
11 species), however, among bats captured over water in the predominantly ponderosa pine forests 
of the eastern Cascade Mountains of south-central Washington (Baker and Lacki, 2004). Netting 
results at 52 sites sampled in predominantly ponderosa pine forests of the eastern Cascades in both 
Washington and Oregon suggested they were locally common but rare across all study locations 
(Lacki and Baker, 2007). 
Fringed myotis were not captured among 231 individuals of nine species of bats netted over 
water in the Pryor Mountains of south-central Montana (Worthington, 1991). This species ranked 
eighth in relative abundance (six individuals) among 12 species and 958 bats captured over water 
