Checklist of lichens of Alaska (USA)
Version 31 December 2018
- Acarospora badiofusca (Nyl.) Th. Fr. - Thomson (1997: 21)
- Acarospora fuscata (Nyl.) Arnold - Thomson (1997: 24)
- Acarospora glaucocarpa (Wahlenb.) Körb. - Thomson (1997: 25)
- Acarospora schleicheri (Ach.) A. Massal. - Thomson (1997: 33)
- Acarospora sinopica (Wahlenb.) Körb. - Spribille et al. (2010: 467)
- Acarospora veronensis A. Massal. - Thomson (1997: 35), Flock (2011: 16)
- Adelolecia pilati (Hepp) Hertel & Hafellner - Thomson (1997: 37), Spribille et al. (2010: 467)
- Agonimia gelatinosa (Ach.) M. Brand & Diederich - Thomson (1997: 480 as Polyblastia gelatinosa)
- Agonimia tristicula (Nyl.) Zahlbr. - Spribille et al. (2010: 467)
- Ahtiana pallidula (Tuck. ex Riddle) Goward & A. Thell - Howe (1911: xx erroneously as Cetraria oakesiana fide Spribille et al.), Riddle (1915: xx), Spribille et al. (2010: 467)
- Alectoria nigricans (Ach.) Nyl. - Howard (1958: 87), Thomson (1984: 35), Geiser et al. (1998: 209), Flock (2011: 16)
- Alectoria ochroleuca (Hoffm.) A. Massal. - Howard (1958: 87), Thomson (1984: 37), Geiser et al. (1998: 209), Flock (2011: 16)
- Alectoria sarmentosa (Ach.) Ach. - Geiser et al. (1998: 209)
- Alectoria vexillifera (Nyl.) Stizenb. - Geiser et al. (1998: 209 as Alectoria sarmentosa subsp. vexillifera)
- Allantoparmelia almquistii (Vain.) Essl. - Thomson (1984: 297 sub Parmelia almquistii), Geiser et al. (1998: 209)
- Allantoparmelia alpicola Th. Fr. - Thomson (1984: 299 sub Parmelia alpicola), Geiser et al. (1998: 209), Flock (2011: 16)
- Allocetraria madreporiformis (Ach.) Kärnefelt & A. Thell - Thomson (1984: 206 as Dactylina madreporiformis)
- Amandinea cacuminum (Th. Fr.) H. Mayrhofer & Sheard - Thomson (1997: 561 as Rinodina cacuminum)
- Amandinea coniops (Wahlenb. in Ach.) M. Choisy ex Scheid. & H. Mayrhofer - Thomson (1997: 128 as Buellia coniops), Geiser et al. (1998: 209)
- Amandinea polyspora (Willey in Tuck.) Vain. - Thomson (1997: 137 as Buellia polyspora)
- Amandinea punctata (Hoffm.) Coppins & Scheid. - Thomson (1997: 138 as Buellia punctata), Geiser et al. (1998: 209), Flock (2011: 16)
- Amygdalaria consentiens (Nyl.) Hertel, Brodo & Mas. Inoue - Geiser et al. (1998: 209)
- Amygdalaria continua Brodo & Hertel - Geiser et al. (1998: 209)
- Amygdalaria elegantior (H. Magn.) Hertel & Brodo - Thomson (1997: 41), Geiser et al. (1998: 209)
- Amygdalaria haidensis Brodo & Hertel - Geiser et al. (1998: 209)
- Amygdalaria panaeola (Ach.) Hertel & Brodo - Thomson (1997: 42), Geiser et al. (1998: 209), Flock (2011: 16)
- Amygdalaria pelobotryon (Wahlenb. in Ach.) Norman - Thomson (1997: 43), Geiser et al. (1998: 209), Flock (2011: 16)
- Amygdalaria subdissentiens (Nyl.) Mas. Inoue & Brodo - Geiser et al. (1998: 209)
- Anaptychia crinalis (Schleich.) Vezda ex J. Nowak - Thomson (1984: 40 erroneously as Anaptychia kaspica)
- Arctocetraria nigricascens (Nyl.) Kärnefelt & A. Thell - Thomson (1984: 90 as Cetraria nigricascens)
- Arctomia delicatula Th. Fr. - Geiser et al. (1998: 209)
- Arctoparmelia centrifuga (L.) Hale - Howard (1958: 90 sub Parmelia centrifuga), Thomson (1984: 476 as Xanthoparmelia centrifuga), Flock (2011: 16)
- Arctoparmelia incurva (Pers.) Hale - Thomson (1984: 478 as Xanthoparmelia incurva), Geiser et al. (1998: 209)
- Arctoparmelia separata (Th. Fr.) Hale - Thomson (1984: 479 as Xanthoparmelia separata), Geiser et al. (1998: 209)
- Arthonia mediella Nyl. - Thomson (1997: 47)
- Arthonia phaeobaea (Norman) Norman - Geiser et al. (1998: 209)
- Arthonia punctiformis Ach. - Geiser et al. (1998: 209)
- Arthrorhaphis alpina (Schaer.) Sant. - Thomson (1997: 50)
- Arthrorhaphis citrinella (Ach.) Poelt - Geiser et al. (1998: 210)
- Asahinea chrysantha (Tuck.) W. L. Culb. & C. F. Culb. - Thomson (1984: 44), Geiser et al. (1998: 210), Flock (2011: 16)
- Asahinea scholanderi (Llano) W. L. Culb. & C. F. Culb. - Llano (1951: 197 as Cetraria scholanderi Type in Washington, USA US), Thomson (1984: 45)
- Aspicilia aliena (Zahlbr.) Oxner - Thomson (1997: 58)
- Aspicilia annulata (Lynge) J. W. Thomson - Thomson (1997: 60)
- Aspicilia anseris (Lynge) J. W. Thomson - Thomson (1997: 61)
- Aspicilia aquatica Körb. - Thomson (1997: 62)
- Aspicilia candida (Anzi) Hue - Thomson (1997: 67)
- Aspicilia cinerea (L.) Körb. - Thomson (1997: 68)
- Aspicilia cingulata (Zahlbr.) Oxner - Thomson (1997: 70)
- Aspicilia concinna (J. W. Thomson) J. W. Thomson - Thomson (1972: 358 as Lecanora concinna [as 'concinnum'] Type), Thomson (1997: 72)
- Aspicilia contigua (Lynge) J. W. Thomson - Thomson (1997: 72)
- Aspicilia disserpens (Zahlbr.) Räsänen - Thomson (1997: 74), Flock (2011: 17)
- Aspicilia elevata (Lynge) J. W. Thomsen - Thomson (1997: 75)
- Aspicilia fimbriata (H. Magn.) Clauz. & Rondon - Thomson (1997: 76)
- Aspicilia heteroplaca (Zahlbr.) Oxner - Thomson (1997: 78)
- Aspicilia lesleyana Darbish. - Thomson (1997: 79)
- Aspicilia pergibbosa (H. Magn.) Räsänen - Thomson (1997: 87)
- Aspicilia perradiata (Nyl.) Hue - Thomson (1997: 88)
- Aspicilia plicigera (Zahlbr.) Räsänen - Thomson (1997: 90 )
- Aspicilia rosulata Körb. - Thomson (1997: 90)
- Aspicilia ryrkaipiae (H. Magn.) Oxner - Thomson (1997: 92)
- Aspicilia subradians (Nyl.) Hue - Thomson (1997: 94)
- Aspicilia supertegens Arnold - Thomson (1997: 95)
- Aspilidea myrinii (Fr. in Myrin) Hafellner - Thomson (1997: 85 as Aspicilia myrinii)
- Athallia holocarpa (Hoffm.) xxx - Thomson (1997: 164 as Caloplaca holocarpa), Geiser et al. (1998: 212 as Caloplaca holocarpa), Flock (2011: 17 as Caloplaca holocarpa)
- Athallia vitellinula (Nyl.) Arup, Frödén & Søchting - Flock (2011: 17 as Caloplaca vitellinula)
- Bacidia alaskensis (Nyl.) Zahlbr. - Nylander (xx: xx as Protologue) Type
- Bacidia bagliettoana (A. Massal. & De Not. in A. Massal.) Jatta - Thomson (1997: 99), Flock (2011: 17)
- Bacidia beckhausii Körb. - Thomson (1997: 100), Geiser et al. (1998: 210)
- Bacidia rubella (Hoffm.) A. Massal. - Thomson (1997: 107)
- Bacidia subincompta (Nyl.) Arnold - Thomson (1997: 110)
- Bactrosporum cascadensis Ponzetti & McCune - McCune & Ponzetti (2011: 2)
- Baeomyces carneus (Retz.) Flörke - Thomson (1984: 48)
- Baeomyces placophyllus Ach. - Thomson (1984: 49), Geiser et al. (1998: 210), Flock (2011: 17)
- Baeomyces rufus (Huds.) Rebent. - Thomson (1984: 52), Geiser et al. (1998: 210)
- Bellemerea alpina (Sommerf.) Clauz. & Roux - Thomson (1997: 115)
- Bellemerea cinereorufescens (Ach.) Clauz. & Roux - Thomson (1997: 116), Geiser et al. (1998: 210)
- Bellemerea subsorediza (Lynge) Sant. - Thomson (1997: 117)
- Biatora aegrefaciens Printzen - Printzen et al. (2002: 38)
- Biatora alaskana Printzen & Tønsberg - Printzen & Tønsberg (1999: 696 Type)
- Biatora cuprea (Sommerf.) Fr. - Geiser et al. (1998: 210)
- Biatora ligni-mollis T. Sprib. & Printzen - Thomson (1997: 325 as Lecidea albohyalina)
- Biatora oligocarpa Printzen & Tønsberg - Printzen & Tønsberg (2004: 352 Type in BG)
- Biatora subduplex (Nyl.) Printzen - Flock (2011: 17)
- Biatora vernalis (L.) Fr. - Geiser et al. (1998: 210)
- Biatorella hemisphaerica Anzi - Thomson (1997: 119)
- Bilimbia lobulata (Sommerf.) Hafellner & Coppins - Flock (2011: 22 as Mycobilimbia lobulata)
- Bilimbia sabuletorum (Schreb.) Arnold - Thomson (1997: 422 as Mycobilimbia sabuletorum), Flock (2011: 22 as Mycobilimbia sabuletorum)
- Blastenia ammiospila (Ach.) Arup, Søchting & Frödén - Thomson (1997: 151 as Caloplaca ammiospila), Flock (2011: 17 as Caloplaca ammiospila)
- Blastenia ferruginea (Huds.) A. Massal. - Geiser et al. (1998: 212 as Caloplaca ferruginea)
- Blennothallia crispa (Weber ex F. H. Wigg.) Otálora, P.M. Jørg. & Wedin - Thomson (1984: 183 as Collema crispum)
- Brigantiaea fuscolutea (Dicks.) R. Sant. - Thomson (1997: 120), Geiser et al. (1998: 210)
- Brodoa oroarctica (Krog) Goward - Thomson (1984: 239 as Hypogymnia oroarctica), Geiser et al. (1998: 210), Flock (2011: 17)
- Bryobilimbia hypnorum (Lib.) Fryday, Printzen & S. Ekman - Thomson (1997: 351 as Lecidea hypnorum)
- Bryocaulon divergens (Ach.) Kärnefelt - Howard (1958: 89 as Cornicularia divergens), Thomson (1984: 199 as Cornicularia divergens), Geiser et al. (1998: 210), Flock (2011: 17)
- Bryocaulon pseudosatoanum (Asah.) Kärnefelt - Geiser et al. (1998: 210)
- Bryonora castanea (Hepp) Poelt - Thomson (1997: 122)
- Bryonora curvescens (Mudd) Poelt - Thomson (1997: 122)
- Bryoplaca jungermanniae (Vahl) Søchting, Frödén & Arup - Thomson (1997: 166 as Caloplaca jungermanniae)
- Bryoplaca tetraspora (Nyl.) Oliv. - Thomson (1997: 172 as Caloplaca tetraspora), Flock (2011: 17 as Caloplaca tetraspora)
- Bryoria bicolor (Ehrh.) Brodo & D. Hawksw. - Geiser et al. (1998: 210)
- Bryoria capillaris (Ach.) Brodo & D. Hawksw. - Thomson (1984: 55), Geiser et al. (1998: 210)
- Bryoria carlottae Brodo & D. Hawksw. - Geiser et al. (1998: 210)
- Bryoria cervinula Motyka ex Brodo & D. Hawksw. - Geiser et al. (1998: 210)
- Bryoria chalybeiformis (L.) Brodo & D. Hawksw. - Thomson (1984: 56), Geiser et al. (1998: 211), Flock (2011: 17)
- Bryoria friabilis Brodo & D. Hawksw. - Geiser et al. (1998: 211)
- Bryoria fuscescens (Gyeln.) Brodo & D. Hawksw. - Howard (1958: 87 sub Alectoria jubata), Thomson (1984: 57), Geiser et al. (1998: 211)
- Bryoria glabra (Motyka) Brodo & D. Hawksw. - Thomson (1984: 58), Geiser et al. (1998: 211)
- Bryoria lanestris (Ach.) Brodo & D. Hawksw. - Thomson (1984: 59), Geiser et al. (1998: 211)
- Bryoria nadvornikiana (Gyeln.) Brodo & D. Hawksw. - Thomson (1984: 61), Geiser et al. (1998: 211)
- Bryoria nitidula (Th. Fr.) Brodo & D. Hawksw. - Thomson (1984: 63), Geiser et al. (1998: 211)
- Bryoria pseudofuscescens (Gyeln.) Brodo & D. Hawksw. - Thomson (1984: 63), Geiser et al. (1998: 211)
- Bryoria simplicior (Vain.) Brodo & D. Hawksw. - Thomson (1984: 65)
- Bryoria subcana (Nyl. ex Stizenb.) Brodo & D. Hawksw. - Geiser et al. (1998: 211)
- Bryoria tenuis (E. Dahl) Brodo & D. Hawksw. - Thomson (1984: 66), Geiser et al. (1998: 211)
- Bryoria trichodes (Michx.) Brodo & D. Hawksw. subsp. trichodes - Thomson (1984: 68), Geiser et al. (1998: 211)
- Buellia aethalea (Ach.) Th. Fr. - Thomson (1997: 125)
- Buellia disciformis (Fr.) Mudd - Thomson (1997: 129), Flock (2011: 17)
- Buellia elegans Poelt - Thomson (1997: 130)
- Buellia erubescens Arnold - Thomson (1997: 131), Geiser et al. (1998: 211)
- Buellia spuria (Schaer.) Anzi - Geiser et al. (1998: 211)
- Buellia stigmatea Körb. - Thomson (1997: 140)
- Buellia vilis Th. Fr. - Thomson (1997: 141)
- Bunodophoron melanocarpum A. Massal. - Geiser et al. (1998: 211)
- Caeruleum heppii (Nägeli ex Körb.) K. Knudsen & B. Abbott - Thomson (1997: 28 as Acarospora heppii)
- Calicium adaequatum Nyl. - Geiser et al. (1998: 211)
- Calicium lenticulare Ach. - Geiser et al. (1998: 212)
- Calicium viride Pers. - Geiser et al. (1998: 212)
- Callome multipartita (Sm.) Otálora, P.M. Jørg. & Wedin - Thomson (1984: 189 as Collema multipartitum)
- Caloplaca atrosanguinea (G. K. Merr.) I. M. Lamb - Geiser et al. (1998: 212)
- Caloplaca cerina (Ehrh. ex Hedwig) Th. Fr. - Thomson (1997: 154), Flock (2011: 17)
- Caloplaca exsecuta (Nyl.) Dalla Torre & Sarnth. - Thomson (1997: 160)
- Caloplaca fraudans (Th. Fr.) Oliv. - Thomson (1997: 162)
- Caloplaca litoricola Brodo - Geiser et al. (1998: 212)
- Caloplaca phaeocarpella (Nyl.) Zahlb. - Thomson (1997: 168)
- Caloplaca pollinii (A. Massal.) Jatta - Geiser et al. (1998: 212)
- Caloplaca saxicola (Hoffm.) Nordin - Thomson (1997: 169)
- Caloplaca stillicidiorum (Vahl) Lynge - Thomson (1997: 172)
- Caloplaca tornoensis H. Magn. - Thomson (1997: 175)
- Calvitimela aglaea (Sommerf.) Hafellner - Thomson (1997: 600 as Tephromela aglaea)
- Calvitimela armeniaca (DC. in Lam. & DC.) xxx - Thomson (1997: 60 as Tephromela armeniaca)
- Candelaria concolor (Dicks.) Stein - Geiser et al. (1998: 212)
- Candelariella arctica (Körb.) R. Sant. - Thomson (1997: 180)
- Candelariella aurella (Hoffm.) Zahlbr. - Thomson (1997: 182), Geiser et al. (1998: 212), Flock (2011: 17)
- Candelariella canadensis H. Magn. - Geiser et al. (1998: 212)
- Candelariella citrina xxx - Thomson (1997: 187 as Candelariella terrigena)
- Candelariella lutella (Vain.) Räsänen - Thomson (1997: 185)
- Candelariella placodizans (Nyl.) H. Magn. - Thomson (1997: 186)
- Candelariella vitellina (Hoffm.) Müll. Arg. - Thomson (1997: 189), Flock (2011: 18)
- Candelariella xanthostigma (Ach.) Lettau - Thomson (1997: 190)
- Carbonea vitellinaria (Nyl.) Hertel - Thomson (1997: 192)
- Carbonea vorticosa (Flörke) Hertel - Thomson (1997: 193), Geiser et al. (1998: 212)
- Catapyrenium cinereum (Pers.) Körb. - Thomson (1984: 211 as Dermatocarpon cinereum)
- Catillaria chalybeia (Borrer) A. Massal. - Thomson (1997: 196)
- Catillaria muscicola Lynge - Thomson (1997: 198)
- Catillaria subnegans (Nyl.) Boistel - Thomson (1997: 200)
- Catolechia wahlenbergii (Ach.) Körb. - Thomson (1997: 202)
- Cetraria aculeata (Schreb.) Fr. - Thomson (1984: 198 sub Cornicularia aculeata), Thomson (1984: 200 sub Cornicularia muricata), Geiser et al. (1998: 212)
- Cetraria ericetorum Opiz - Howard (1958: 87 as Cetraria tenuifolia), Thomson (1984: 79), Geiser et al. (1998: 212), Flock (2011: 18)
- Cetraria islandica (L.) Ach. subsp. islandica - Howard (1958: 87), Thomson (1984: 84), Geiser et al. (1998: 212 inclusive subsp. crispiformis and subsp. orientalis), Flock (2011: 18)
- Cetraria kamczatica Savicz - Thomson (1984: 86), Flock (2011: 18)
- Cetraria laevigata Rass. - Thomson (1984: 88), Flock (2011: 18)
- Cetraria muricata (Ach.) Eckfeldt - Geiser et al. (1998: 212)
- Cetraria nigricans (Retz.) Nyl. in Esslinger nur Nyl. - Thomson (1984: 89), Flock (2011: 18)
- Cetrariella commixta (Nyl.) A. Thell & Kärnefelt - Thomson (1984: 75 as Cetraria commixta), Flock (2011: 18 as Cetraria commixta)
- Cetrariella delisei (Bory ex Schaer.) Kärnefelt & A. Thell - Thomson (1984: 77 as Cetraria delisei), Flock (2011: 18 as Cetrariella delisei)
- Cetrariella fastigiata (Delise ex Nyl.) Kärnefelt & A. Thell - Thomson (1984: 80 as Cetraria fastigiata), Flock (2011: 18)
- Cetrelia alaskana (C. F. Culb. & W. L. Culb.) W. L. Culb. & C. L. Culb. - Culberson & Culberson (xx: xx as Cetraria alaskana Protologue), Culberson & Culberson (xx: xx), Thomson (1984: 97), Flock (2011: 18) Type
- Chaenotheca furfuracea (L.) Tibell - Thomson (1997: 210 as Coniocybe furfuracea)
- Circinaria caesiocinerea (Nyl. ex Malbr.) A. Nordin, Savić & Tibell - Thomson (1997: 65 as Aspicilia caesiocinerea)
- Circinaria gibbosa (Ach.) A. Nordin, S. Savić & Tibell - Geiser et al. (1998: 210 as Aspicilia gibbosa)
- Cladonia aberrans (Abbayes) Stuckenb. - Abbayes (1939: 93 Protologue), Stuckenberg (1956: 12), Ahti (1961: xx Lectotypification) Type in W
- Cladonia acuminata ( Ach.) Norrl. - Thomson (1984: 105), Thomson (1984: 152 as Cladonia norrlinii)
- Cladonia alaskana Evans - Evans (1947: 35 Protologue), Thomson (1984: 106) Type in Washington, USA US
- Cladonia amaurocraea (Flörke) Schaer. - Thomson (1984: 107), Flock (2011: 18)
- Cladonia arbuscula (Wallr.) Rabenh. subsp. arbuscula - Howard (1958: 89 as Cladonia sylvatica)Thomson (1984: 110)
- Cladonia arbuscula (Wallr.) Rabenh. subsp. beringiana Ahti - Flock (2011: 18)
- Cladonia bacillaris (Ach.) Nyl. - Thomson (1984: 111)
- Cladonia bacilliformis (Nyl.) xxx - Thomson (1984: 112)
- Cladonia bellidiflora (Ach.) Schaer. - Howard (1958: 88), Thomson (1984: 113), Flock (2011: 18)
- Cladonia botrytes (K. G. Hagen) Willd. - Thomson (1984: 114)
- Cladonia cariosa (Ach.) Spreng. - Thomson (1984: 116), Flock (2011: 18)
- Cladonia carneola (Fr.) Fr. - Thomson (1984: 117)
- Cladonia cenotea (Ach.) Schaer. - Howard (1958: 88), Thomson (1984: 118)
- Cladonia chlorophaea (Flörke ex. Sommerf.) Spreng. - Howard (1958: 88), Thomson (1984: 119)
- Cladonia coccifera (L.) Willd. - Howard (1958: 88), Thomson (1984: 121), Flock (2011: 19)
- Cladonia coniocraea (Flörke) Spreng. - Thomson (1984: 122)
- Cladonia cornuta (L.) Hoffm. - Thomson (1984: 124)
- Cladonia crispata (Ach.) Flot. - Thomson (1984: 125), Flock (2011: 19)
- Cladonia cryptochlorophaea Asah. - Thomson (1984: 126)
- Cladonia cyanipes (Somm.) Nyl. - Thomson (1984: 127)
- Cladonia decorticata (Flörke) Spreng. - Thomson (1984: 128), Flock (2011: 19)
- Cladonia deformis (L.) Hoffm. - Howard (1958: 88), Thomson (1984: 129), Flock (2011: 19)
- Cladonia digitata (L.) Hoffm. - Thomson (1984: 131)
- Cladonia ecmocyna Leight. - Thomson (1984: 132), Flock (2011: 19)
- Cladonia fimbriata (L.) Fr. - Thomson (1984: 133), Thomson (1984: 144 as Cladonia major)
- Cladonia glauca Flörke - Thomson (1984: 135)
- Cladonia gracilis (L.) Willd. subsp. turbinata (Ach.) Ahti - Thomson (1984: 136)
- Cladonia gracilis (L.) Willd. subsp. gracilis - Thomson (1984: 137 as Cladonia gracilis var. gracilis), Flock (2011: 19 as Cladonia gracilis var. gracilis)
- Cladonia gracilis (L.) Willd. subsp. vulnerata Ahti - Ahti (1980: 207 Type in Helsinki, Finland H), Ahti (1993: 79)
- Cladonia granulans Vain. - Thomson (1984: 139)
- Cladonia grayi G. Merr. ex Sandst. - Thomson (1984: 139)
- Cladonia humilis (With.) J. R. Laundon - Thomson (1984: 123 as Cladonia conista)
- Cladonia kanewskii Oxner - Thomson (1984: 140)
- Cladonia macrophylla (Schaer.) Stenham. - Thomson (1984: 141)
- Cladonia macrophyllodes Nyl. - Thomson (1984: 143)
- Cladonia maxima (Asah.) Ahti - Thomson (1984: 145), Flock (2011: 19)
- Cladonia merochlorophaea Asah. - Thomson (1984: 143)
- Cladonia mitis Sandst. - Howard (1958: 89), Thomson (1984: 148), Flock (2011: 19)
- Cladonia multiformis Merr. - Thomson (1984: 149)
- Cladonia nipponica Asah. - Thomson (1984: 150)
- Cladonia phyllophora Ehrh. ex Hoffm. - Thomson (1984: 153)
- Cladonia pleurota (Flörke) Schaer. - Howard (1958: 89), Thomson (1984: 154), Flock (2011: 19)
- Cladonia pocillum (Ach.) O. J. Rich. - Howard (1958: 89 as Cladonia pyxidata var. pocillum), Thomson (1984: 156)
- Cladonia pseudostellata Asah. - Thomson (1984: 157)
- Cladonia pyxidata (L.) Hoffm. - Thomson (1984: 158)
- Cladonia ramulosa (Ach.) Ahti & P. James - Thomson (1984: 109 as Cladonia anomaea)
- Cladonia rangiferina (L.) Wigg. - Howard (1958: 89), Thomson (1984: 159), Flock (2011: 19)
- Cladonia scabriuscula (Del. in Duby) Nyl. - Thomson (1984: 160)
- Cladonia squamosa (Scop.) Hoffm. - Howard (1958: 89), Thomson (1984: 161)
- Cladonia stellaris (Opiz) Pouzar & Vezda - Howard (1958: 88 as Cladonia alpestris), Thomson (1984: 104 as Cladonia aberrans), Thomson (1984: 163), Flock (2011: 19)
- Cladonia straminea (Sommerf.) Flörke - Thomson (1984: 147 as Cladonia metacorallifera)
- Cladonia stricta (Nyl.) Nyl. - Thomson (1984: 164), Flock (2011: 19)
- Cladonia subfurcata (Nyl.) Arnold - Thomson (1984: 166), Flock (2011: 19)
- Cladonia subulata (L.) Wigg. - Howard (1958: 88 as Cladonia cornutoradiata), Thomson (1984: 168)
- Cladonia sulphurina (Michx.) Fr. - Thomson (1984: 169)
- Cladonia symphycarpia (Ach.) Fr. - Thomson (1984: 170)
- Cladonia thomsonii Ahti - Ahti (1978: 334 Type in Helsinki, Finland H), Thomson (1984: 171), Ahti (1993: 99)
- Cladonia turgida Ehrh. ex Hoffm. - Thomson (1984: 172)
- Cladonia uncialis (L.) Weber ex F. H. Wigg. - Howard (1958: 89), Thomson (1984: 173), Flock (2011: 19)
- Cladonia verticillata (Hoffm.) Schaer. - Thomson (1984: 174)
- Cladonia wainioi Savicz - Thomson (1984: 157 as Cladonia pseudorangiformis)
- Clauzadea monticola (Ach. in Schaer.) Hafellner & Bellem. - Thomson (1984: 208), Flock (2011: 19)
- Coccocarpia erythroxyli (Spreng.) Swinscow & Krog - Thomson (1984: 176)
- Coccotrema pocillarium (Cummings) Brodo - Cummings in Cardot et al. (1904: 101 Protologue), Brodo (1973: 267) Type in CANL
- Collema flaccidum (Ach.) Ach. - Thomson (1984: 186)
- Collema furfuraceum (Arnold) DuRietz - Thomson (1984: 187)
- Collema glebulentum (Nyl. ex Crombie) Degel. Thomson (1984: 185)
- Collema leptaleum Tuck.- Nelson et al. (2011: 3)
- Cornicularia normoerica (Gunn.) DuRietz - Thomson (1984: 201)
- Cyphelium inquinans (Sm. in Sm. & Sow.) Trevisan - Thomson (1997: 212)
- Cyphelium tigillare (Ach.) Ach. - Thomson (1997: 214)
- Dactylina arctica (Richards.) Nyl. - Howard (1958: 89), Thomson (1984: 203), Flock (2011: 19)
- Dactylina beringica Bird & Thoms. - Thomson (1984: 204), Flock (2011: 19)
- Dactylina ramulosa (Hook.) Tuck. - Thomson (1984: 207)
- Dendriscocaulon umhausense (Auersw.) Degel. - Thomson (1984: 371 as Polychidium umhausense)
- Dermatocarpon arnoldianum Degel. - Thomson (1984: 210)
- Placidium squamulosum xxx - Thomson (1984: 215 erronneously as Dermatocarpon hepaticum)
- Dermatocarpon intestiniforme (Körb.) Hasse - Thomson (1984: 216)
- Dermatocarpon miniatum (L.) Mann. - Thomson (1984: 219)
- Dermatocarpon rivulorum (Arnold) Dalla Torre & Sarnth. - Thomson (1984: 220)
- Dibaeis baeomyces (L. f.) Rambold & Hertel - Thomson (1984: 51 as Baeomyces roseus)
- Dimelaena oreina (Ach.) Norman - Thomson (1997: 216)
- Diploschistes muscorum (Scop.) R. Sant. - Thomson (1997: 218)
- Diploschistes scruposus (Schreb.) Norman - Thomson (1997: 218)
- Diplotomma alboatrum (Hoffm.) Flot. - Thomson (1997: 134 as Buellia nivalis), Geiser et al. (1998: 211 as Buellia alboatra)
- Diplotomma epipolium (Ach.) Arnold - Thomson (1967: 461 as Rhizocarpon cumulatum Type), Feuerer (1991: 173 as Buellia epipolia), Thomson (1997: 530 as Rhizocarpon cumulatum)
- Diplotomma nivale (Bagl. & Carestia) Hafellner - Bagl. & Carestia (1864: 84 as Leciographa nivalis)
- Eiglera flavida (Hepp) Hafellner - Thomson (1997: 220)
- Enchylium bachmanianum (Fink) Otálora, P. M. Jørg. & Wedin - Thomson (1984: 179 as Collema bachmanianum)
- Enchylium polycarpon (Hoffm.) Otálora, P. M. Jørg. & Wedin -Thomson (1984: 190 as Collema polycarpon)
- Enchylium tenax (Sw.) Gray - Thomson (1984: 191 as Collema tenax)
- Ephebe hispidula (Ach.) Horwood - Flock (2011: 19)
- Epilichen scabrosus (Ach.) Clem. ex Hafellner - Thomson (1997: 221)
- Erioderma pedicellatum (Hue) P. M. Jørg. - Nelson et al. (2009: 19 First record), Stehn et al. (2013: 2)
- Euopsis granatina (Sommerf.) Nyl. - Thomson (1997: 223), Flock (2011: 20)
- Euopsis pulvinata (Schaer.) Vain. - Flock (2011: 20)
- Evernia mesomorpha Nyl. - Thomson (1984: 229)
- Evernia perfragilis Llano - Thomson (1984: 230), Flock (2011: 20)
- Evernia prunastri (L.) Ach. - Howard (1958: 89)
- Farnoldia jurana (Schaer.) Hertel - Thomson (1997: 225), Flock (2011: 20)
- Flavocetraria cucullata (Bell.) Ach. - Howard (1958: 87 sub Cetraria cucullata), Thomson (1984: 76 sub Cetraria cucullata), Flock (2011: 20)
- Flavocetraria nivalis (L.) Kärnefelt & A. Thell - Howard (1958: 87 as Cetraria nivalis), Thomson (1984: 92 as Cetraria nivalis), Flock (2011: 20)
- Flavoplaca citrina (Hoffm.) Arup, Frödén & Søchting - Geiser et al. (1998: 212 as Caloplaca citrina)
- Flavoplaca marina (Wedd.) Arup, Frödén & Søchting - Thomson (1997: 166 as Caloplaca marina)
- Fuscopannaria praetermissa (Nyl.) P. M. Jørg. - Thomson (1984: 320 as Parmeliella praetermissa)
- Gyalolechia bracteata (Hoffm.) A. Massal. - Thomson (1997: 228 as Fulgensia bracteata)
- Fuscidea lowensis (H. Magn.) Anderson & Hertel - Thomson (1997: 232)
- Fuscidea mollis (Wahlenb.) V. Wirth & Vezda - Thomson (1997: 233)
- Glypholecia scabra (Pers.) Müll. Arg. - Thomson (1997: 236)
- Gyalecta foveolaris (Ach.) Schaer. - Thomson (1997: 238)
- Gyalidea lecideopsis (A. Massal.) Lettau ex Vezda - Thomson (1997: 243)
- Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup - Thomson (1997: 161 as Caloplaca flavovirescens)
- Gyalolechia xanthostigmoidea (Räsänen) Søchting, Frödén & Arup - Thomson (1997: 158 as Caloplaca discolor), Flock (2011: 17 as Caloplaca epiphyta)
- Halecania alpivaga (Th. Fr.) M. Mayrhofer - Thomson (1997: 257 as Lecania alpivaga), Flock (2011: 20 as Lecania disceptans)
- Heppia lutosa (Ach.) Nyl. - Thomson (1997: 244)
- Herteliana alaskensis (Nyl.) S. Ekman - Thomson (1997: 98 as Bacidia alaskensis)
- Hymenelia epulotica (Ach.) Lutzoni - Thomson (1997: 253 as Ionaspis epulotica)
- Hymenelia heteromorpha (Kremp.) Lutzoni - Thomson (1997: 254 as Ionaspis reducta), Thomson (1997: 255 as Ionaspis schismatopsis)
- Hymenelia melanocarpa (Kremp.) Arnold - Thomson (1997: 254 as Ionaspis melanocarpa)
- Hymenelia rhodopis (Sommerf.) Lutzoni - Thomson (1997: 252 as Ionaspis ochromicra)
- Hypocenomyce scalaris (Ach. ex Lilj.) M. Choisy - Thomson (1997: 248)
- Hypogymnia austerodes (Nyl.) Räsänen - Thomson (1984: 237)
- Hypogymnia bitteri (Lynge) Ahti - Thomson (1984: 238)
- Hypogymnia hultenii (Degel.) Krog - Geiser et al. (1998: 212 as Cavernularia hultenii)
- Hypogymnia lophyrea (Ach.) Krog - Geiser et al. (1998: 212 as Cavernularia lophyrea)
- Hypogymnia physodes (L.) Nyl. - Howard (1958: 90 as Parmelia physodes), Thomson (1984: 241)
- Hypogymnia pulverata (Nyl. ex Crombie) Elix - Nelson et al. (2011: 3)
- Hypogymnia subobscura (Vain.) Poelt - Thomson (1984: 242), Flock (2011: 20)
- Hypogymnia vittata (Ach.) Gas. - Thomson (1984: 243)
- Icmadophila ericetorum (L.) Zahlbr. - Howard (1958: 89), Thomson (1997: 249)
- Immersaria carbonoidea (J. W. Thomson) M. Barbero, Nav.-Ros. & Cl. Roux - Thomson (1972: 356 as Lecidea carbonoidea Type), Thomson (1997: 334 as Lecanora carbonoidea)
- Ionaspis lacustris (With.) Lutzoni - Thomson (1997: 245 as Hymenelia lacustris)
- Lasallia pensylvanica (Hoffm.) Llano - Thomson (1984: 246)
- Lathagrium fuscovirens (With.) Otálora, P. M. Jørg. & Wedin - Thomson (1984: 192 as Collema tuniforme)
- Lathagrium undulatum (Laurer ex Flot.) Poetsch - Thomson (1984: 194 as Collema undulatum), Flock (2011: 19 as Collema undulatum)
- Lecania subfuscula (Nyl.) S. Ekman - Thomson (1997: 108 as Bacidia sibiriensis), Thomson (1997: 111 as Bacidia subfuscula), Flock (2011: 16 as Bacidia subfuscula)
- Lecanora albellula (Nyl.) Th. Fr. var. albellula - Thomson (1997: 299 as Lecanora piniperda)
- Lecanora aleutica H. Magn. - Thomson (1997: 265), Flock (2011: 20)
- Lecanora argentea xxx - Thomson (1997: 281 as Lecanora fuliginosa)
- Lecanora argopholis (Ach.) Ach. - Thomson (1997: 267)
- Lecanora atrosulphurea (Wahlenb.) Ach. - Thomson (1997: 267), Flock (2011: 20)
- Lecanora caesiosulphurea Vain. - Thomson (1997: 271)
- Lecanora circumborealis Brodo & Vitik. - Thomson (1997: 274), Flock (2011: 20)
- Lecanora crenulata Hook. - Thomson (1997: 277)
- Lecanora epibryon (Ach.) Ach. - Thomson (1997: 279), Flock (2011: 20)
- Lecanora geophila (Th. Fr.) Poelt - Thomson (1997: 283)
- Lecanora intricata (Ach.) Ach. - Thomson (1997: 288)
- Lecanora leptacina Sommerf. - Thomson (1997: 289)
- Lecanora luteovernalis Brodo - Thomson (1997: 290)
- Lecanora marginata (Schaer.) Hertel & Rambold - Thomson (1997: 291)
- Lecanora microfusca Lynge - Thomson (1997: 294)
- Lecanora nordenskioeldii Vain. - Thomson (1997: 296)
- Lecanora orae-frigidae R. Sant. - Thomson (1997: 297), Flock (2011: 20)
- Lecanora polytropa (Ehrh. in Hoffm.) Rabenh. - Thomson (1997: 299), Flock (2011: 21)
- Lecanora pulicaris - Thomson (1997: 301)
- Lecanora rupicola (L.) Zahlbr. - Thomson (1997: 303)
- Lecanora salicicola H. Magn. - Thomson (1997: 304)
- Lecanora saxicola (Pollich) Ach. - Thomson (1997: 295 as Lecanora muralis)
- Lecanora straminea (Wahlenb.) Ach. - Thomson (1997: 306), Flock (2011: 21)
- Lecanora subintricata (Nyl.) Th. Fr. - Thomson (1997: 307)
- Lecanora symmicta (Ach.) Ach. - Thomson (1997: 309), Flock (2011: 21)
- Lecanora torrida Vain. - Thomson (1997: 310)
- Lecanora varia (Hoffm.) Ach. - Thomson (1997: 311)
- Lecanora xylophila Hue - Thomson (1997: 284 as Lecanora grantii)
- Lecidea alpestris (Ramond ex Lam. & DC.) Schaerer - Thomson (1997: 326)
- Lecidea atrobrunnea (Ramond ex Lam. & DC.) Schaerer - Thomson (1997: 327)
- Lecidea atrofulva Sommerf. - Thomson (1997: 328)
- Lecidea auriculata Th. Fr. - Thomson (1997: 329)
- Lecidea berengeriana (A. Massal.) Th. Fr. - Thomson (1997: 331)
- Lecidea brachyspora (Th. Fr.) Nyl. - Thomson (1997: 333)
- Lecidea caesioatra Schaer. - Flock (2011: 21)
- Lecidea cinnabarina Sommerf. - Thomson (1997: 336)
- Lecidea confluens (W. A. Weber) Ach. - Thomson (1997: 339)
- Lecidea cuprea Sommerf. - Thomson (1997: 341)
- Lecidea diapensiae Th. Fr. - Thomson (1997: 342)
- Lecidea diducens Nyl. - Thomson (1997: 343)
- Lecidea ecrustacea (Anzi ex Arnold) Arnold - Thomson (1997: 343)
- Lecidea ementiens Nyl. - Thomson (1997: 344)
- Lecidea fuscoatra (L.) Ach. - Thomson (1997: 347)
- Lecidea hypocrita A. Massal. - Thomson (1997: 353)
- Lecidea lactea Flörke ex Schaerer - Thomson (1997: 355)
- Lecidea lapicida (Ach.) Ach. - Thomson (1997: 357), Flock (2011: 21)
- Lecidea leucophaea (Flörke ex Rabenh.) Nyl. - Thomson (1997: 359)
- Lecidea leucothallina Arnold - Thomson (1997: 360)
- Lecidea limosa Ach. - Thomson (1997: 361)
- Lecidea lithophila (Ach.) Ach. - Thomson (1997: 362)
- Lecidea pallida Th. Fr. - Thomson (1997: 367)
- Lecidea parasemella Nyl. - Thomson (1997: 366)
- Lecidea paupercula Th. Fr. - Thomson (1997: 369)
- Lecidea plebeja Nyl. - Thomson (1997: 374)
- Lecidea ramulosa Th. Fr. - Thomson (1997: 376)
- Lecidea steineri Hertel - Thomson (1997: 380)
- Lecidea subcandida H. Magn. - Thomson (1997: 381)
- Lecidea tessellata Flörke - Thomson (1997: 384)
- Lecidea tornoënsis Nyl. - Thomson (1997: 387)
- Lecidea turgidula Fr. - Thomson (1997: 388)
- Lecidea umbonata (Hepp.) Mudd - Thomson (1997: 389)
- Lecidea vernalis (L.) Ach. - Thomson (1997: 389)
- Lecidella bullata Körb. - Thomson (1997: 393)
- Lecidella carpathica Körb. - Thomson (1997: 395)
- Lecidella elaeochroma (Ach.) Hazslin - Thomson (1997: 396)
- Lecidella euphorea (Flörke) Hertel - Thomson (1997: 398), Flock (2011: 21)
- Lecidella inamoena (Müll. Arg.) Hertel - Thomson (1997: 399)
- Lecidella stigmatea (Ach.) Hertel & Leuck. - Thomson (1997: 402), Flock (2011: 21)
- Lecidella wulfenii (Hepp) Körb. - Thomson (1997: 403)
- Lecidoma demissum (Rutstr.) Schneider & Hertel - Thomson (1997: 405), Flock (2011: 21)
- Leciophysma finmarkicum Th. Fr. - Thomson (1984: 248), Flock (2011: 21)
- Leciophysma furfurascens (Nyl.) Gyel. - Thomson (1984: 249)
- Lempholemma radiatum (Sommerf.) Henssen - Thomson (1997: 407)
- Lepra dactylina (Ach.) Hafellner - Thomson (1997: 453 as Pertusaria dactylina), Flock (2011: 23 as Pertusaria dactylina)
- Leprocaulon subalbicans (J. M. Lamb) J. M. Lamb & Ward - Thomson (1984: 250)
- Leproplaca cirrochroa (Ach.) Th. Fr. - Thomson (1997: 155 as Caloplaca cirrochroa)
- Leptochidium albociliatum (Desm.) M. Choisy - Thomson (1984: 252)
- Leptogium arcticum P. M. Jørg. - Thomson (1984: 255)
- Leptogium lichenoides (L.) Otálora, P. M. Jørg. & Wedin - Thomson (1984: 257)
- Leptogium lichenoides (L.) Zahlbr. var. pulvinatum (Hoffm.) Zahlbr. - Howard (1958: 89)
- Leptogium palmatum (Huds.) Mont. in Webb. & Berth. - Thomson (1984: 260)
- Leptogium saturninum (Dicks.) Nyl. Thomson (1984: 262)
- Leptogium sinuatum (Huds.) A. Massal. - Thomson (1984: 263)
- Lichenomphalia hudsoniana (H. S. Jenn.) Redhead, Lutzoni, Moncalvo & Vilgalys - Thomson (1984: 196 as Coriscium viride), Flock (2011: 24 as Phytoconis viridis)
- Lithographa tesserata (DC.) Nyl. - Flock (2011: 21)
- Lobaria hallii (Tuck.) Zahlbr. - Thomson (1984: 266)
- Lobaria kurokawae Yoshim. - Thomson (1984: 267)
- Lobaria linita (Ach.) Rabenh. - Howard (1958: 89), Thomson (1984: 269), Flock (2011: 21)
- Lobaria pseudopulmonaria Gyeln. - Thomson (1984: 270)
- Lobaria pulmonaria (L.) Hoffm. - Howard (1958: 89), Nelson et al. (2009: 20)
- Lobaria scrobiculata (Scop.) DC. - Thomson (1984: 271), Nelson et al. (2009: 20)
- Lobothallia alphoplaca (Wahlenb. in Ach.) xxx - Thomson (1997: 59 as Aspicilia alphoplaca)
- Lobothallia melanaspis (Ach.) Poelt & Leuck. - Thomson (1997: 82 as Aspicilia melanaspis)
- Lopadium coralliodeum (Nyl.) Lynge - Thomson (1997: 409), Flock (2011: 21)
- Lopadium pezizoideum (Ach.) Körb. - Thomson (1997: 411), Flock (2011: 21)
- Masonhalea inermis (Nyl.) Lumbsch, M. Nelsen & A. Thell - Thomson (1984: 83 as Cetraria inermis)
- Masonhalea richardsonii (Hook.) Kärnef. - Howard (1958: 87 sub Cetraria richardsonii), Thomson (1984: 273), Flock (2011: 21)
- Massalongia carnosa (Dicks.) Körb. - Thomson (1984: 274)
- Megalaria jemtlandica (Th. Fr. & Almq.) Fryday - Thomson (1997: 197 as Catillaria jemtlandica)
- Megaspora verrucosa (Ach.) Hafellner & V. Wirth in V. Wirth - Flock (2011: 22)
- Melanelia hepatizon (Ach.) A. Thell - Thomson (1984: 82 as Cetraria hepatizon), Flock (2011: 18 as Cetraria hepatizon)
- Melanelia stygia (L.) Essl. - Flock (2011: 22)
- Melanelixia fuliginosa (Fr. ex Duby) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 303 sub Parmelia glabratula)
- Melanelixia subaurifera (Nyl.) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 316 sub Parmelia subaurifera)
- Melanohalea elegantula (Zahlbr.) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 300 sub Parmelia elegantula)
- Melanohalea exasperatula (Nyl.) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 300 sub Parmelia exasperatula)
- Melanohalea infumata (Nyl.) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 304 sub Parmelia infumata)
- Melanohalea olivacea (L.) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Howard (1958: 90 sub Parmelia olivacea), Thomson (1984: 306 sub Parmelia olivacea)
- Melanohalea olivaceoides (Krog) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 306 sub Parmelia olivaceoides)
- Melanohalea septentrionalis (Lynge) O. Blanco, A. Crespo, Divakar, Essl., D. Hawksw. & Lumbsch - Thomson (1984: 311 sub Parmelia septentrionalis)
- Micarea assimilata (Nyl.) Coppins - Thomson (1997: 413)
- Micarea crassipes (Th. Fr.) Coppins - Thomson (1997: 414)
- Micarea incrassata Hedl. - Thomson (1997: 416), Flock (2011: 22)
- Micarea lignaria (Ach.) Hedl. - Thomson (1997: 417)
- Micarea melaena (Nyl.) Hedl. - Thomson (1997: 419)
- Micarea ternaria (Nyl.) Vezda - Thomson (1997: 420)
- Micarea turfosa (A. Massal.) Du Rietz - Thomson (1997: 420)
- Montanelia disjuncta (Erichsen) Divakar, A. Crespo, Wedin & Essl. - Thomson (1984: 299 sub Parmelia disjuncta)
- Montanelia panniformis (Nyl.) Divakar, A. Crespo, Wedin & Essl. - Thomson (1984: 309 sub Parmelia panniformis)
- Montanelia sorediata (Ach.) Divakar, A. Crespo, Wedin & Essl. - Thomson (1984: 312 sub Parmelia sorediosa)
- Montanelia tominii (Oxner) Divakar, A. Crespo, Wedin & Essl. - Thomson (1984: 317 sub Parmelia substygia)
- Mycobilimbia berengeriana (A. Massal.) Hafellner & V. Wirth - Flock (2011: 22)
- Mycobilimbia microcarpa (Th. Fr.) Brunnb. - Thomson (1997: 105 as Bacidia microcarpa)
- Mycobilimbia pilularis (Hepp ex Körb.) Hafellner & Türk - Thomson (1997: 110 as Bacidia sphaeroides), Flock (2011: 17 as Biatora sphaeroides)
- Mycobilimbia tetramera (De Not.) Vitik., Ahti, Kuusinen, Lommi & T. Ulvinen ex Hafellner & Türk - Thomson (1997: 422 as Mycobilimbia obscurata)
- Mycoblastus affinis (Schaer.) T. Schauer - Thomson (1997: 424), Flock (2011: 22)
- Mycoblastus alpinus (Fr.) Kernst. - Thomson (1997: 425)
- Mycoblastus marginatus Degel. - Thomson (1997: 424)
- Mycoblastus sanguinarius (L.) Norman - Thomson (1997: 426), Flock (2011: 22)
- Myriolecis dispersa (Pers.) Sliwa, Zhao Xin & Lumbsch - Thomson (1997: 278)
- Myriolecis hagenii (Ach.) Sliwa, Zhao Xin & Lumbsch - Thomson (1997:286), Flock (2011: 20)
- Myriolecis zosterae (Ach.) Sliwa, Zhao Xin & Lumbsch - Thomson (1997: 270 as Lecanora behringii), Thomson (1997: 312 as Lecanora zosterae), Flock (2011: 20 as Lecanora behringii)
- Myriospora smaragdula (Wahlenb.) Nägeli - Thomson (1997: 34 as Acarospora smaragdula)
- Nephroma arcticum (L.) Torss. - Howard (1958: 89), Thomson (1984: 277), Flock (2011: 22)
- Nephroma bellum (Spreng.) Tuck. - Thomson (1984: 278)
- Nephroma expallidum (Nyl.) Nyl. - Thomson (1984: 279)
- Nephroma isidiosum (Nyl.) Gyeln. - Thomson (1984: 281), Nelson et al. (2009: 20)
- Nephroma parile (Ach.) Ach. - Thomson (1984: 282)
- Nephroma resupinatum (L.) Ach. - Thomson (1984: 283)
- Nephromopsis andrejevii (Oxner) Divakar, A. Crespo & Lumbsch - Thomson (1984: 72 as Cetraria andrejevii), Flock (2011: 16 as Arctocetraria andrejevii)
- Ochrolechia alaskana (Verseghy) Kukwa - Verseghy (1958: 76 as Ochrolechia frigida f. alaskana Type in Helsinki, Finland H)
- Ochrolechia androgyna (Hoffm.) Arnold - Thomson (1997: 430)
- Ochrolechia frigida (Sw.) Lynge - Howard (1958: 90), Thomson (1997: 431), Flock (2011: 22)
- Ochrolechia grimmiae Lynge - Thomson (1997: 432), Flock (2011: 22)
- Ochrolechia gyalectina (Nyl.) Zahlbr. - Thomson (1997: 433), Flock (2011: 22)
- Ochrolechia inaequatula (Nyl.) Zahlbr. - Howard (1958: 90), Thomson (1997: 434)
- Ochrolechia subplicans (Nyl.) Brodo - Thomson (1997: 435), Flock (2011: 22)
- Ochrolechia tartarea (L.) A. Massal. - Howard (1958: 90)
- Ochrolechia upsaliensis (L.) A. Massal. - Howard (1958: 90), Thomson (1997: 436)
- Ochrolechia xanthostoma (Sommerf.) K. Schmitz & Lumbsch - Thomson (1997: 464 as Pertusaria xanthostoma)
- Opegrapha saxicola Ach. - Thomson (1997: 438)
- Ophioparma lapponica (Räsänen) Hafellner & R. W. Rogers - Thomson (1997: 440), Flock (2011: 22)
- Ophioparma ventosa (L.) Norman - Howard (1958: 89 sub Haematomma ventosum)
- Orphniospora moriopsis (A. Massal.) D. Hawksw. - Thomson (1997: 441)
- Pachyospora verrucosa (Ach.) A. Massal. - Thomson (1997: 443 as Pachyospora verrucosa)
- Pachypeltis invadens Lynge ex Søchting, Frödén & Arup - Thomson (1997: 165 as Caloplaca invadens)
- Parmelia fraudans (Nyl.) Nyl. - Thomson (1984: 302)
- Parmelia omphalodes (L.) Ach. - Howard (1958: 90), Thomson (1984: 308), Flock (2011: 23)
- Parmelia saxatilis (L.) Ach. - Howard (1958: 90), Thomson (1984: 310), Flock (2011: 23)
- Parmelia skultii Hale - Hale (1987: 43 Type in Washington, USA US), Flock (2011: 23)
- Parmelia squarrosa Hale - Hale (1971: 29)
- Parmelia sulcata Taylor - Howard (1958: 90), Thomson (1984: 318)
- Parmeliella arctophila (Th. Fr.) Malme - Thomson (1984: 320)
- Parmeliopsis aleurites (Ach.) Nyl. em. Lettau - Thomson (1984: 321)
- Parmeliopsis ambigua (Wulf.) Nyl. - Thomson (1984: 325), Flock (2011: 23)
- Parmeliopsis hyperopta (Ach.) Arnold - Thomson (1984: 326)
- Parvoplaca tiroliensis (Zahlbr.) Arup, Søchting & Frödén - Thomson (1997: 173 as Caloplaca tiroliensis)
- Peltigera aphthosa (L.) Willd. var. aphthosa - Howard (1958: 90), Thomson (1984: 329)
- Peltigera aphthosa (L.) Willd. var. variolosa (A. Massal.) Thomson - Howard (1958: 90)
- Peltigera canina (L.) Willd. var. canina - Howard (1958: 91)
- Peltigera canina (L.) Willd. var. albescens (Wahlbr.) Thomson - Howard (1958: 91)
- Peltigera canina (L.) Willd. f. sorediata Schaer. - Thomson (1984: 332)
- Peltigera collina (Ach.) Schrad. - Thomson (1984: 334)
- Peltigera horizontalis (Huds.) Baumg. - Thomson (1984: 337)
- Peltigera lepidophora (Nyl.) Vain. - Thomson (1984: 338)
- Peltigera leucophlebia (Nyl.) Gyeln. - Thomson (1984: 330 as Peltigera aphthosa var. leucophlebia), Flock (2011: 23)
- Peltigera malacea (Ach.) Funck - Howard (1958: 91), Thomson (1984: 339)
- Peltigera membranacea (Ach.) Nyl. - Thomson (1984: 340), Flock (2011: 23)
- Peltigera polydactyla (Neck.) Hoffm. - Thomson (1984: 343)
- Peltigera polydactyla var. crassoides Gyeln. - Howard (1958: 91)
- Peltigera rufescens (Weis.) xxx - Thomson (1984: 333 as Peltigera canina var. rufescens)
- Peltigera scabrosa Th. Fr. - Thomson (1984: 344), Flock (2011: 23)
- Peltigera venosa (L.) Baumg. - Thomson (1984: 345)
- Pertusaria alaskensis Erichsen - Erichsen (1938: 350 Type in Hamburg, Germany HBG), Thomson (1997: 446), Flock (2011: 23)
- Pertusaria alpina Hepp ex Ahles - Thomson (1997: 447)
- Pertusaria bryontha (Ach.) Nyl. - Thomson (1997: 449), Flock (2011: 23)
- Pertusaria bryophaga Erichsen - Thomson (1997: 450)
- Pertusaria carneopallida (Nyl.) Anzi ex Nyl. - Thomson (1997: 451)
- Pertusaria coriacea (Th. Fr.) Th. Fr. - Thomson (1997: 452), Flock (2011: 23)
- Pertusaria excludens Nyl. - Thomson (1997: 455)
- Pertusaria geminipara (Th. Fr.) Knight ex Brodo - Thomson (1997: 455)
- Pertusaria glomerata (Ach.) Schaerer - Thomson (1997: 456), Flock (2011: 23)
- Pertusaria octomela (Norman) Erichsen - Thomson (1997: 457)
- Pertusaria oculata (Dickson) Th. Fr. - Thomson (1997: 458), Flock (2011: 23)
- Pertusaria panyrga (Ach.) A. Massal. - Thomson (1997: 459), Flock (2011: 24)
- Pertusaria sommerfeltii (Flörke ex Sommerf.) Fr. - Thomson (1997: 461)
- Pertusaria subdactylina Nyl. - Thomson (1997: 461)
- Pertusaria subobducens Nyl. - Thomson (1997: 462), Flock (2011: 24)
- Pertusaria trochisea Norman - Thomson (1997: 463)
- Phaeophyscia constipata (Nyl.) Moberg - Thomson (1984: 347)
- Phaeophyscia endococcina (Körb.) Moberg - Thomson (1984: 348)
- Phaeophyscia sciastra (Ach.) Moberg - Thomson (1984: 349), Flock (2011: 24)
- Phaeorrhiza nimbosa (Fr.) H. Mayrhofer & Poelt - Thomson (1997: 467)
- Phylliscum demangeonii (Moug. & Mont.) Nyl. - Thomson (1997: 469)
- Physcia adscendens H. Olivier - Thomson (1984: 352)
- Physcia aipolia (Ehrh. ex Humb.) Fürnr. - Thomson (1984: 353)
- Physcia caesia (Hoffm.) Hampe ex Fürnr. - Thomson (1984: 354)
- Physcia dubia (Hoffm.) Lettau - Thomson (1984: 355)
- Physconia detersa (Nyl.) Poelt - Thomson (1984: 359)
- Physconia muscigena (Ach.) Poelt - Howard (1958: 91 sub Physcia muscigena), Thomson (1984: 360)
- Pilophorus cereolus (Ach.) Th. Fr. in Hellbom - Flock (2011: 24)
- Pilophorus dovrensis (Nyl.) Timdal, Hertel & Rambold - Flock (2011: 24)
- Pilophorus robustus Th. Fr. - Thomson (1984: 363), Flock (2011: 24)
- Placidium lachneum (Ach.) B. de Lesd. - Thomson (1984: 217 as Dermatocarpon lachneum)
- Placopsis cribellans (Nyl.) Räsänen - Thomson (1997: 471)
- Placopsis gelida (L.) Linds. - Thomson (1997: 472), Flock (2011: 24)
- Placynthiella oligotropha (J. R. Laundon) Coppins & P. James - Thomson (1997: 474)
- Placynthiella uliginosa (Schrad.) Coppins & P. James - Thomson (1997: 475)
- Placynthium asperellum (Ach.) Trevisan - Thomson (1984: 365 as Placynthium aspratile), Flock (2011: 24)
- Placynthium nigrum (Huds.) Gray - Thomson (1984: 366), Flock (2011: 24)
- Platismatia glauca (L.) C. F. Culb. & W. L. Culb. - Howard (1958: 87 sub Platismatia clauca sic!), Thomson (1984: 368)
- Pleopsidium chlorophanum (Wahlenb.) Zopf - Thomson (1997: 22 as Acarospora chlorophana)
- Polyblastia cucurbitula W. Thomson & B. M. Murray - Flock (2011: 24)
- Polyblastia gothica Th. Fr. - Thomson (1997: 480)
- Polyblastia hyperborea Th. Fr. - Thomson (1997: 481)
- Polyblastia theleodes (Sommerf.) Th. Fr. - Thomson (1997: 484), Flock (2011: 24)
- Polycauliona candelaria (L.) Frödén, Arup, & Søchting - Howard (1958: 92 as Xanthoria candelaria), Thomson (1984: 483 as Xanthoria candelaria), Flock (2011: 28 as Xanthoria candelaria)
- Polycauliona flavogranulosa (Arup) Arup, Frödén & Søchting - Geiser et al. (1998: 212 as Caloplaca flavogranulosa)
- Polycauliona polycarpa (Ehrh.) Rieber - Thomson (1984: 487 as Xanthoria polycarpa)
- Polycauliona verruculifera (Vain.) Arup, Frödén & Søchting -Thomson (1997: 177 as Caloplaca verruculifera), Geiser et al. (1998: 212 as Caloplaca verruculifera)
- Polychidium muscicola (Sw.) Gray - Thomson (1984: 370), Flock (2011: 24)
- Polysporina simplex (Davis) Vezda - Thomson (1997: 486)
- Porocyphus coccodes (Flot.) Körb. - Thomson (1997: 488)
- Porpidia flavicunda (Ach.) Gowan - Thomson (1997: 491)
- Porpidia flavocaerulescens (Hornem.) Hertel & A. J. Schwab - Thomson (1997: 492), Flock (2011: 24)
- Porpidia grisea Gowan - Gowan (1989: 48 Type in WIS), Thomson (1997: 493)
- Porpidia lowiana Gowan - Thomson (1997: 494)
- Porpidia speirea (Ach.) Kremp. - Thomson (1997: 497), Flock (2011: 25)
- Porpidia superba (Körb.) Hertel & Knoph - Thomson (1997: 498)
- Porpidia thomsonii Gowan - Thomson (1997: 498), Flock (2011: 25)
- Porpidia tuberculosa (Sm. in Sm. & Sow.) Hertel & Knoph - Thomson (1997: 500)
- Porpidia zeoroides (Anzi) Knoph & Hertel - Thomson (1997: 500), Flock (2011: 25)
- Protoblastenia calva (Dickson) Zahlbr. - Thomson (1997: 502), Flock (2011: 25)
- Protoblastenia rupestris (Scop.) Steiner - Thomson (1997: 503), Flock (2011: 25)
- Protoblastenia terricola (Anzi) Lynge - Thomson (1997: 503)
- Protopannaria pezizoides (Weber) P. M. Jørg. & S. Ekman - Thomson (1984: 294 as Pannaria pezizoides), Flock (2011: 23 as Pannaria pezizoides)
- Protoparmelia badia (Hoffm.) Hafellner - Thomson (1997: 269 as Lecanora badia), Flock (2011: 25)
- Protoparmeliopsis peltata (Ramond) Arup, Zhao Xin & Lumbsch - Thomson (1997: 555 as Rhizoplaca peltata)
- Protothelenella sphinctrinoides (Nyl.) Mayrh. & Poelt - Thomson (1997: 505)
- Pseudephebe minuscula (Nyl. ex Arn.) Brodo & D. Hawksw. - Thomson (1984: 373)
- Pseudephebe pubescens (L.) M. Choisy - Howard (1958: 90 sub Parmelia pubescens), Thomson (1984: 374), Flock (2011: 25)
- Pseudocyphellaria anomala Brodo & Ahti - Nelson et al. (2009: 20)
- Pseudocyphellaria crocata (L.) Vain. - Nelson et al. (2009: 20)
- Psora decipiens (Hedwig) Hoffm. - Thomson (1997: 507)
- Psora globifera (Ach.) A. Massal. - Thomson (1997: 508)
- Psora himalayana (Bab.) Timdal - Thomson (1997: 507), Flock (2011: 25)
- Psora nipponica (Zahlbr.) Schneider - Thomson (1997: 510)
- Psora rubiformis (Ach.) Hook. - Thomson (1997: 511)
- Psora tenuifolia Timdal - Thomson (1997: 512)
- Psoroma hypnorum (Vahl) Gray - Thomson (1984: 375), Flock (2011: 25)
- Pyrenopsis myriospora Dahl - Thomson (1997: 517)
- Pyrenopsis pulvinata (Schaer.) Th. Fr. - Thomson (1997: 518)
- Ramboldia gowardiana (T. Sprib. & Hauck) Kalb, Lumbsch & Elix - Spribille & Hauck (2003: 560 as Pyrrhospora gowardiana)
- Ramalina almquistii Vain. - Howard (1958: 91), Thomson (1984: 232 as Fisturiella almquistii), Flock (2011: 25)
- Ramalina pollinaria (Westr.) Ach. - Thomson (1984: 381)
- Ramalina roesleri (Hoechst. ex Schaer.) Hue - Thomson (1984: 233 as Fisturiella roesleri)
- Ramalina scoparia Vain. - Thomson (1984: 234 as Fisturiella scoparia), Flock (2011: 25)
- Ramalina thrausta (Ach.) Nyl. - Thomson (1984: 382), Elix & Tønsberg (2005: 36)
- Rhizocarpon alaxensis J. W. Thomson - Thomson (1997: 522)
- Rhizocarpon anseris Lynge - Thomson (1997: 523)
- Rhizocarpon badioatrum (Flörke ex Sprengel) Th. Fr. - Thomson (1997: 524)
- Rhizocarpon chinoneum (Norman) Th. Fr. - Thomson (1997: 527), Flock (2011: 25)
- Rhizocarpon concentricum (Davis) Beltr. - Thomson (1997: 529)
- Rhizocarpon copelandii (Körb.) Th. Fr. - Thomson (1997: 531), Flock (2011: 25)
- Rhizocarpon eupetraeoides (Nyl.) Blomb. & Forssell - Thomson (1997: 532)
- Rhizocarpon eupetraeum (Nyl.) Arnold - Thomson (1997: 533), Flock (2011: 25)
- Rhizocarpon geminatum Körb. - Thomson (1997: 537)
- Rhizocarpon geographicum (L.) DC. - Thomson (1997: 538), Thomson (1997: 548 as Rhizocarpon riparium), Flock (2011: 25)
- Rhizocarpon grande (Flörke ex Flot.) Arnold - Thomson (1997: 539)
- Rhizocarpon hochstetteri (Körb.) Vain. - Thomson (1997: 540)
- Rhizocarpon inarense (Vain.) Vain. - Thomson (1997: 541), Flock (2011: 25)
- Rhizocarpon norvegicum Räsänen - Thomson (1997: 544)
- Rhizocarpon polycarpum (Hepp) Th. Fr. - Thomson (1997: 546)
- Rhizocarpon pusillum Runemark - Thomson (1997: 547)
- Rhizocarpon rittokense (Hellb.) Th. Fr. - Thomson (1997: 549)
- Rhizocarpon superficiale (Schaer.) Malme - Thomson (1997: 551), Flock (2011: 25)
- Rhizocarpon umbilicatum (Ramond) Flagey - Thomson (1997: 552)
- Rhizoplaca chrysoleuca (Sm.) Zopf - Thomson (1997: 554)
- Rhizoplaca melanophthalma (Ram.) Leuck. & Poelt - Thomson (1997: 555)
- Rinodina archaea (Ach.) Arnold - Thomson (1997: 560)
- Rinodina bischoffii (Hepp.) A. Massal. - Thomson (1997: 561)
- Rinodina calcigena (Th. Fr.) Lynge - Thomson (1997: 562)
- Rinodina granulans Vain. - Thomson (1997: 564)
- Rinodina mniaraea (Ach.) Körb. - Thomson (1997: 567)
- Rinodina mucronatula H. Magn. - Thomson (1997: 568)
- Rinodina notabilis (Lynge) Sheard - Thomson (1997: 134 as Buellia notabilis)
- Rinodina pallidescens Sheard & Tønsberg - Sheard et al. (2014: 254 Type in )
- Rinodina roscida (Sommerf.) Arnold - Thomson (1997: 569), Flock (2011: 25)
- Rinodina septentrionalis Malme - Thomson (1997: 570)
- Rinodina sheardii Tønsberg - Tønsberg (1992: 216 Type in BG)
- Rinodina turfacea (Wahlenb.) Körb. - Thomson (1997: 571), Flock (2011: 25)
- Ropalospora lugubris (Sommerf.) Poelt - Thomson (1997: 571), Flock (2011: 26)
- Rostania ceranisca (Nyl.) xxx - Thomson (1984: 182 as Collema ceraniscum)
- Rusavskia elegans (Link) S. Y. Kondr. & Kärnefelt - Howard (1958: 87 sub Caloplaca elegans), Thomson (1984: 484 as Xanthoria elegans), Flock (2011: 28 as Xanthoria elegans var. splendens)
- Rusavskia sorediata (Vain.) S. Y. Kondr. & Kärnefelt - Thomson (1984: 487 as Xanthoria sorediata), Flock (2011: 28 as Xanthoria sorediata)
- Sagiolechia rhexoblephara (Nyl.) Zahlbr. - Thomson (1997: 575)
- Sarcogyne regularis Körb. - Thomson (1997: 579)
- Sarcosagium campestre (Fr.) Poetsch & Schiedem. - Thomson (1997: 119 as Biatorella campestris)
- Schadonia fecunda (Th. Fr.) Vezda & Poelt - Thomson (1997: 581)
- Schaereria cinereorufa (Schaer.) Th. Fr. - Thomson (1997: 582)
- Schaereria tenebrosa (Flot.) Hertel & Poelt - Thomson (1997: 584)
- Scytinium callopismum (A. Massal.) xxx - Thomson (1984: 180 as Collema callopismum)
- Scytinium tenuissimum (Hoffm.) Otálora, P.M. Jørg. & Wedin - Thomson (1984: 264 as Leptogium tenuissimum)
- Silobia scabrida (H. Magn.) M. Westb. & Wedin - Thomson (1997: 32 as Acarospora scabrida)
- Siphula ceratites (Wahlenb.) Fr. - Howard (1958: 91), Thomson (1984: 384), Flock (2011: 26)
- Solorina bispora Nyl. - Thomson (1984: 386), Flock (2011: 26)
- Solorina crocea (L.) Ach. - Howard (1958: 91), Thomson (1984: 387), Flock (2011: 26)
- Solorina octospora (Arnold) Arnold - Thomson (1984: 389), Flock (2011: 26)
- Solorina saccata (L.) Ach. - Thomson (1984: 390), Flock (2011: 26)
- Solorina spongiosa (Sm.) Anzi - Thomson (1984: 391), Flock (2011: 26)
- Sphaerophorus fragilis (L.) Pers. - Thomson (1984: 393), Flock (2011: 26)
- Sphaerophorus globosus (Huds.) Vain. - Howard (1958: 91), Thomson (1984: 394), Flock (2011: 26)
- Sphinctrina turbinata (Pers. ex Fr.) de Not. - Thomson (1997: 568)
- Spilonema revertens Nyl. - Flock (2011: 26)
- Sporastatia polyspora (Nyl.) Grumm. - Thomson (1997: 588), Flock (2011: 26)
- Sporastatia testudinea (Ach.) A. Massal. - Thomson (1997: 589)
- Staurothele areolata (Ach.) Lettau - Thomson (1997: 592)
- Staurothele discendens (Nyl.) Zahlbr. - Thomson (1997: 593)
- Staurothele drummondii (Tuck.) Tuck. - Thomson (1997: 595)
- Staurothele fissa (Tayler) Zwackh. - Thomson (1997: 596)
- Stereocaulon alpinum Laur. - Howard (1958: 91), Thomson (1984: 400), Flock (2011: 26)
- Stereocaulon apocalypticum Nyl. - Thomson (1984: 401 as "apocalyptum"), Flock (2011: 26)
- Stereocaulon arcticum Lynge - Thomson (1984: 402), Flock (2011: 26)
- Stereocaulon arenarium (Sav.) I. M. Lamb - Thomson (1984: 403), Flock (2011: 27)
- Stereocaulon botryosum Ach. em. Frey - Thomson (1984: 405), Flock (2011: 27)
- Stereocaulon coniophyllum I. M. Lamb - Thomson (1984: 409)
- Stereocaulon dactylophyllum Flörke - Thomson (1984: 410)
- Stereocaulon glareosum (Sav.) H. Magn. - Thomson (1984: 412), Flock (2011: 27)
- Stereocaulon grande (H. Magn.) H. Magn. - Thomson (1984: 413), Flock (2011: 27)
- Stereocaulon groenlandicum (E. Dahl) I. M. Lamb - Thomson (1984: 414)
- Stereocaulon incrustatum Flörke - Thomson (1984: 415)
- Stereocaulon intermedium (Sav.) H. Magn. - Howard (1958: 91), Thomson (1984: 417), Flock (2011: 27)
- Stereocaulon nivale (Follmann) Fryday - Geiser et al. (1998: 210 as Bacidia nivalis)
- Stereocaulon paschale (L.) Hoffm. - Howard (1958: 91), Thomson (1984: 418), Flock (2011: 27)
- Stereocaulon rivulorum H. Magn. - Thomson (1984: 421), Flock (2011: 27)
- Stereocaulon saviczii Du Rietz - Thomson (1984: 422)
- Stereocaulon saxatile H. Magn. - Thomson (1984: 423)
- Stereocaulon spathuliferum Vain. - Thomson (1984: 425)
- Stereocaulon subcoralloides (Nyl.) Nyl. - Thomson (1984: 426)
- Stereocaulon symphycheilum I. M. Lamb - Thomson (1984: 426)
- Stereocaulon tomentosum E. Fries - Howard (1958: 91), Thomson (1984: 428)
- Stereocaulon vesuvianum Pers. - Thomson (1984: 430), Flock (2011: 27)
- Sticta arctica Degel. - Thomson (1984: 433)
- Sticta weigelii (Isert ex Ach.) Vain. - Thomson (1984: 434)
- Strigula sychnogonioides (Nitschke) R. C. Harris - Thomson (1997: 234 as Geisleria sychnogonioides)
- Tephromela atra (Huds.) Hafellner - Thomson (1997: 633)
- Tetramelas papillatus (Sommerf.) Kalb - Thomson (1997: 136 as Buellia papillata), Geiser et al. (1998: 211 as Buellia papillata)
- Tetramelas pulverulentus (Anzi) A. Nordin & Tibell - Thomson (1997: 137 as Buellia pulverulenta)
- Tetramelas terricola (A. Nordin) Kalb - Thomson (1997: 133 erroneously as Buellia geophila)
- Thamnolia subuliformis (Ehrh.) W. L. Culb. - Thomson (1984: 438), Flock (2011: 27)
- Thamnolia vermicularis (Sw.) Ach. - Howard (1958: 91), Thomson (1984: 438), Flock (2011: 27)
- Thelidium aeneovinosum (Anzi) Arnold - Thomson (1997: Arnold 605)
- Thelidium minutulum Körb. - Thomson (1997: 605)
- Thelidium papulare (Fr.) Arnold - Thomson (1997: 607)
- Thelidium pyrenophorum (Ach.) Mudd - Thomson (1997: 607), Flock (2011: 27)
- Thrombium epigaeum (Pers.) Wallr. - Thomson (1997: 610)
- Toninia caeruleonigricans (Lightf.) Th. Fr. - Thomson (1997: 614)
- Toninia cumulata (Sommerf.) Th. Fr. - Thomson (1997: 616)
- Toninia lobulata (Sommerf.) Lynge - Thomson (1997: 617)
- Toninia tristis (Th. Fr.) Th. Fr. - Thomson (1997: 620)
- Trapelia coarctata (Turner ex Sm. & Sow.) M. Choisy - Thomson (1997: 621), Flock (2011: 27)
- Trapeliopsis granulosa (Hoffm.) Lumbsch - Thomson (1997: 624)
- Tremolecia atrata (Ach.) Hertel - Thomson (1997: 627), Flock (2011: 27)
- Tuckermanopsis americana (Sprengel) Hale - Thomson (1984: 81 as Cetraria halei)
- Tuckermanopsis chlorophylla (Willd.) Hale - Thomson (1984: 73 as Cetraria chlorophylla)
- Tuckermanopsis ciliaris (Ach.) Gyeln. - Howard (1958: 89 as Nephromopsis ciliaris)
- Tuckermanopsis sepincola (Ehrh.) Hale - Thomson (1984: 94 as Cetraria sepincola)
- Umbilicaria angulata Tuck. - Thomson (1984: 442), Flock (2011: 27)
- Umbilicaria arctica (Ach.) Nyl. - Thomson (1984: 444), Flock (2011: 27)
- Umbilicaria caroliniana Tuck. - Thomson (1984: 445)
- Umbilicaria cinereorufescens ( Schaer.) Frey - Thomson (1984: 446)
- Umbilicaria cylindrica (L.) Del. in Duby - Thomson (1984: 448), Flock (2011: 28)
- Umbilicaria decussata (Vill.) Zahlbr. - Thomson (1984: 288 as Omphalodiscus decussatus)
- Umbilicaria deusta (L.) Baumg. - Thomson (1984: 449), Flock (2011: 28)
- Umbilicaria hirsuta (Sw.) Ach. - Thomson (1984: 452)
- Umbilicaria hyperborea (Ach.) Hoffm. - Howard (1958: 92), Thomson (1984: 453), Flock (2011: 28)
- Umbilicaria lyngei (Schol.) xxx - Thomson (1984: 28 as Agyrophora lyngei)
- Umbilicaria phaea Tuck. - Thomson (1984: 455)
- Umbilicaria polaris (Schol.) Zahlbr. - Thomson (1984: 289 erroneously as Omphalodiscus krascheninnikovii)
- Umbilicaria polyphylla (L.) Baumg. - Thomson (1984: 457)
- Umbilicaria proboscidea (L.) Schrad. - Howard (1958: 92), Thomson (1984: 458), Flock (2011: 28)
- Umbilicaria rigida (Du Rietz) Frey - Thomson (1984: 33 as Agyrophora rigida)
- Umbilicaria scholanderi (Llano) Krog - Thomson (1984: 33 as Agyrophora scholanderi)
- Umbilicaria torrefacta (Lightf.) Schrad. - Thomson (1984: 459), Flock (2011: 28)
- Umbilicaria vellea (L.) Ach. - Thomson (1984: 460), Flock (2011: 28)
- Umbilicaria virginis Schaer. - Thomson (1984: 290 as Omphalodiscus virginis)
- Usnea cavernosa Tuck. - Thomson (1984: 463)
- Usnea dasopoga (Ach.) Nyl. - Thomson (1984: 465 as Usnea dasypoga)
- Usnea glabrata (Ach.) Vain. - Howard (1958: 92)
- Usnea subfloridana Stirt. - Thomson (1984: 469)
- Usnea substerilis Mot. - Thomson (1984: 470)
- Vahliella globigera (Fryday & P. M. Jørg.) P. M. Jørg. - Fryday (2004: 173 as Fuscopannaria globigera ['globuligera'] Protologue), Jørgensen (2008: 223) Type
- Varicellaria rhodocarpa (Körb.) Th. Fr. - Thomson (1997: 629)
- Verrucaria acrotella Ach. - Thomson (1997: 631)
- Verrucaria aethiobola Wahlenb. - Thomson (1997: 632)
- Verrucaria arctica Lynge - Thomson (1997: 633)
- Verrucaria cateleptoides (Nyl.) Nyl. - Thomson (1997: 634)
- Verrucaria ceuthocarpa Wahlenb. - Thomson (1997: 635)
- Verrucaria devergens Nyl. - Thomson (1997: 635), Flock (2011: 28)
- Verrucaria deversa Vain. - Thomson (1997: 637)
- Verrucaria integra (Nyl.) Nyl. - Thomson (1997: 638)
- Verrucaria margacea (Wahlenb. in Ach.) Wahlenb. - Thomson (1997: 639)
- Verrucaria maura Wahlenb. - Thomson (1997: 640)
- Verrucaria mucosa Wahlenb. - Thomson (1997: 641)
- Verrucaria muralis Ach. - Thomson (1997: 641)
- Verrucaria nigrescens Pers. - Thomson (1997: 642)
- Verrucaria praetermissa (Trevisan) Anzi - Thomson (1997: 643)
- Verrucaria rupestris Schrad. - Thomson (1997: 643)
- Verrucaria striatula Wahlenb. - Thomson (1997: 645)
- Vestergrenopsis elaeina (Wahlenb.) Gyeln. - Thomson (1984: 472)
- Vestergrenopsis isidiata (Degel.) Dahl - Thomson (1984: 473)
- Vulpicida juniperina (L.) J.-E. Mattsson & M. J. Lai - Thomson (1984: 95 as Cetraria tilesii), Flock (2011: 28 as Vulpicida tilesii)
- Vulpicida pinastri (Scop.) S. Gray - Howard (1958: 87 as Cetraria pinastri), Thomson (1984: 93 as Cetraria pinastri)
- Vulpicida tubulosus (Schaer.) J.-E. Mattsson & M. J. Lai - Howard (1958: 88 as )
- Xanthomendoza fallax (Hepp) Söchting, Kärnefelt & S. Kondr. - Thomson (1984: 486 as Xanthoria fallax)
- Xylographa opegraphella Nyl. ex Rothr. - Flock (2011: 28)
- Xylographa parallela (Pers.) Zahlbr. - Thomson (1997: 646 as Xylographa abietina)
- Xylographa vitiligo (Ach.) J. R. Laundon - Anderson (1967: 342), Thomson (1997: 647)