The institutions below are referred to in the text.
CAS California Academy of Sciences, San Francisco, California
IEA Instituto di Entomologia Agraria, Portici/Napoli, Italy (Is this now DEZA?)
KNWR Kenai National Wildlife Refuge, Soldotna, Alaska
PAS Polish Academy of Sciences, Kracov, Poland
UAM University of Alaska Museum of the North, Fairbanks, Alaska
USNM U.S. National Museum of Natural History, Washington D.C.
UWBM Burke Museum of Natural History and Culture, Seattle, Washington
Family Machilidae
Subfamily Machilinae
Genus Mesomachilis
Subgenus Mesomachilis
Mesomachilis leechi Sturm, 1991
Distribution: USA: California (Sturm, 1991).
Type Material: holotype ♂, allotype ♀ and paratype ♂ and ♀ at CAS (Sturm, 1991).
Mesomachilis nearctica Silvestri, 1911
Synonyms: Mixomachilis remingtoni Paclt, 1972
Distribution: USA: Arizona (Mendes, 1992; Sturm, 1991), California (Silvestri, 1911; Paclt, 1972; Sturm, 1991; Baldo et al., 2010), Colorado (Silvestri, 1911), Nevada (Sturm, 1991; Baldo et al., 2010), and Utah (Baldo et al., 2010).
Type Material: Type ♀ and paratype ♂ and ♀ at IEA (Sturm, 1991).
Mesomachilis cf. nearctica sensu Baldo et al. (2010)
Distribution: USA: California, Nevada, and Utah (Baldo et al., 2010).
Mesomachilis strenua (Silvestri, 1911)
Synonyms: Machilis strenua Silvestri, 1911; Pedetontus strenuus Smith, 1970.
Distribution: USA: California (Silvestri, 1911).
Subgenus Rarochilis
Mesomachilis californica Sturm, 1991
Distribution: USA: California (Sturm, 1991).
Type Material: holotype ♂, allotype ♀, and paratype ♂ and ♀ at CAS (Sturm, 1991).
Mesomachilis canadensis Sturm, 1991
Distribution: CANADA: British Columbia (Sturm, 1991). USA: Oregon (KNWR:Ento:8159).
Type Material: holotype ♂; allotype ♀; 9 ♂, 16 ♀, and 14 immature paratypes at USNM (Sturm, 1991).
Mesomachilis sp. A
Distribution: CANADA: British Columbia (KNWR:Ento:8164).
Genus Trigoniophthalmus
Synonyms: Trigoniophthalmus alternatus (Silvestri, 1904); Machilis alternata Silvestri, 1904
Distribution: CANADA: Ontario (Ryan Chlebak, personal communication). USA: New York (Silvestri, 1911; Wygodzinsky and Schmidt, 1980); Connecticut,
Maryland, New Jersey, and Pennsylvania (Wygodzinsky and Schmidt, 1980); Massachusetts and Virginia (BugGuide.Net).
Subfamily Petrobiinae
Genus Leptomachilis
Leptomachilis californica Sturm, 1991
Distribution: USA: California (Sturm, 1991). Type Material: type ♂, allotype ♀, and a paratype ♂ at CAS (Sturm, 1991).
Genus Meximachilis
Meximachilis cokendolpheri Kaplin, 1994
Distribution: USA: New Mexico (Kaplin, 1994).
Meximachilis sp. BOLD:AAV1523
Distribution: USA: Texas (see BOLD BIN BOLD:AAV1523)
Genus Neomachilis
Neomachilis halophila Silvestri, 1911
Synonyms: Neomachilis halophilus Silvestri, 1911
Distribution: USA: California (Silvestri, 1911; Benedetti, 1973; Mendes, 1992).
Genus Pedetontoides
Pedetontoides atlanticus Mendes, 1981
Distribution: USA: North Carolina (Mendes, 1981).
Type Material: holotypes and paratypes at PAS except for two paratype ♀’s in the collection of Luís Mendes (Luís Mendes, personal communication).
Pedetontoides cf. atlanticus
Distribution: CANADA: British Columbia (KNWR:Ento:8191)
Genus Pedetontus
Subgenus Pedetontus
Pedetontus californicus (Silvestri, 1911)
Distribution: USA: California (Silvestri, 1911; Mendes, 1992; Sturm, 2001), Idaho (De Jong, 2014).
Pedetontus saltator Wygodzinsky and Schmidt, 1980
Distribution: USA: Connecticutt, Massachusetts, New Jersey, New York, and Pennsylvania (Wygodzinsky and Schmidt, 1980).
Pedetontus superior (Silvestri, 1911)
Distribution: USA: Oregon (Silvestri, 1911).
Pedetontus schicki Sturm, 2001
Distribution: USA: California (Sturm, 2001).
Pedetontus yosemite Sturm, 2001
Distribution: USA: California (Sturm, 2001).
Subgenus Verhoeffilis
Pedetontus calcaratus (Silvestri, 1911)
Distribution: CANADA: British Columbia (Sturm, 1991; KNWR:Ento:8151, KNWR:Ento:8161). USA: Colorado (Silvestri, 1911; Mendes, 1981).
Pedetontus gershneri Allen, 1995
Distribution: USA: Arkansas (Allen, 1995).
Pedetontus persquamosus (Silvestri, 1911)
Distribution: USA: California (Silvestri, 1911).
Pedetontus submutans (Silvestri, 1911)
Distribution: CANADA: British Columbia (KNWR:Ento:8158). USA: Alaska (UAM:Ento:87248), Oregon (Silvestri, 1911, KNWR:Ento:8197), and Washington (Silvestri, 1911).
Genus Petridiobius
Subgenus Petridiobius
Petridiobius arcticus (Folsom, 1902)
Synonyms: Machilis arctica Folsom, 1902
Distribution: USA: Alaska (Folsom, 1902; Sturm and Bowser, 2004, KNWR:Ento:7292).
Subgenus Pacltiobius
Petridiobius canadensis Sturm, 2001
Distribution: CANADA: British Columbia (Sturm, 2001; KNWR:Ento:8195).
Genus Petrobius
Petrobius brevistylis Carpenter, 1913
Synonyms: Petrobius canadensis Paclt, 1969
Distribution: CANADA: New Brunswick and Nova Scotia (Wygodzinsky and Schmidt, 1980). USA: Maine, Massachusetts, New Hampshire, and Rhode Island (Wygodzinsky and Schmidt, 1980)
Family Meinertellidae
Genus Hypomachiloides
Hypomachiloides forthaysi Packauskas and Shofner, 2010
Distribution: Kansas (Packauskas and Shofner, 2010).
Hypomachiloides texanus Silvestri, 1911
Distribution: Texas (Silvestri, 1911).
Genus Machilinus
Machilinus aurantiacus Schött, 1897
Synonyms: Machilis aurantiacus Schött, 1897; Machilinus nevadensis Sweetman, 1937
Distribution: CANADA: British Columbia (Sturm and Bach de Roca, 1992; KNWR:Ento:8130). USA: California (Silvestri, 1911; Sturm and Bach de Roca, 1992); Colorado (Silvestri, 1911); Arizona, Nevada, and Utah (Sturm and Bach de Roca, 1992).
Machilinus matadero De Jong, 2014
Distribution: USA: Colorado (De Jong, 2014).
Machilinus taoseno De Jong, 2014
Distribution: USA: Arizona, Colorado, New Mexico (De Jong, 2014).
Machilinus zingiberus De Jong, 2014
Distribution: USA: Idaho, Nevada (De Jong, 2014).
Genus Machiloides
Machiloides banksi Silvestri, 1911
Distribution: USA: Arkansas (Allen, 1995; KNWR:Ento:8815/BOLD:TTSOW231-10), Maryland (Wygodzinsky and Schmidt, 1980), Missouri (KNWR:Ento:8876), North Carolina (Mendes, 1981), and Virginia (Silvestri, 1911; Mendes, 1992).
Machiloides petauristes Wygodzinsky and Schmidt, 1980
Distribution: USA: New Jersey (Wygodzinsky and Schmidt, 1980)
Genus Neomachilellus
Neomachilellus sp.
Distribution: USA: Georgia (Sturm, 1984; Wygodzinsky, 1967) and Florida (Wygodzinsky, 1967).