For more information see the Supplementary Notes for the Taxon Dictionary, which explains the names and synonyms, and these Instructions on how to use the online Taxon Dictionary which includes details of the Conservation Evaluation codes.
| Count | Name | Authority | Is Current Name? | Current Taxon Name | Synonyms | BLS Number | Comments | Conservation Evaluation | Group | Account & Map |
|---|---|---|---|---|---|---|---|---|---|---|
| 5221 | Macentina stigonemoides | Orange (1989) | No | Psoroglaena stigonemoides | 1630 | LC | ||||
| 5222 | Macrophomina pseudeverniae | Etayo & Diederich | No | Didymocyrtis pseudeverniae | 2107 | NE NR | LF | |||
| 5223 | Magmopsis argilospila | (Nyl.) Nyl. (1886) | No | Collemopsidium argilospilum | 77 | DD NR IR | ||||
| 5224 | Mallotium burgessii | (L.) Gray (1821) | No | Leptogium burgessii | 830 | LC Sc WaL IR | ||||
| 5225 | Mallotium saturninum | (Dicks.) Gray (1821) | No | Leptogium saturninum | 844 | VU C2 NS P Eng Sc | ||||
| 5226 | Marchandiobasidium aurantiacum | (Lasch) Diederich & Schultheis (2003) | No | Erythricium aurantiacum | 2108 | LC | LF | |||
| 5227 | Marchandiomyces aurantiacus | (Lasch) Diederich & Etayo (1996) | No | Erythricium aurantiacum | 2108 | LC | LF | |||
| 5228 | Marchandiomyces corallinus | (Roberge) Diederich & D. Hawksw. (1990) | Yes | Marchandiomyces corallinus | Illosporium corallinum | 2109 | LC | LF | Marchandiomyces corallinus | |
| 5229 | Marchantiana asserigena | (J. Lahm) Søchting & Arup (2018) | Yes | Marchantiana asserigena | Caloplaca asserigena | 2371 | LC NS | Marchantiana asserigena | ||
| 5230 | Marfloraea albescens | (Huds) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra albescens var. albescens | 1056 | LC | ||||
| 5231 | Marfloraea amara | (Ach.) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra amara | 1058 | LC | ||||
| 5232 | Marfloraea aspergilla | (Ach.) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra aspergilla | 1070 | LC | ||||
| 5233 | Marfloraea corallina | (L.) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra corallina | 1066 | LC | ||||
| 5234 | Marfloraea excludens | (Nyl.) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra excludens | 1071 | LC NS | ||||
| 5235 | Marfloraea ophthalmiza | (Nyl.) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra ophthalmiza | 1085 | LC NS Sc IR | ||||
| 5236 | Marfloraea pulvinata | (Erichsen) S.Y. Kondr., L. Lökös & J.-S. Hur (2015) | No | Lepra pulvinata | 1090 | NE NR | ||||
| 5237 | Massalongia carnosa | (Dicks.) Körb. (1855) | Yes | Massalongia carnosa | Massalongia carnosa var. determinata | 861 | LC | Massalongia carnosa | ||
| 5238 | Massalongia carnosa var. determinata | (Nyl.) A.L. Sm. | No | Massalongia carnosa | 861 | LC | ||||
| 5239 | Massalongia cheilea | Mudd | No | Vahliella leucophaea | 977 | LC | ||||
| 5240 | Massjukiella candelaria | (L.) S.Y. Kondr. et al. (2012) | No | Polycauliona candelaria s. str. | 2364 | LC | ||||
| 5241 | Massjukiella polycarpa | (Hoffm.) S.Y. Kondr. et al. (2012) | No | Polycauliona polycarpa | 1531 | LC | ||||
| 5242 | Massjukiella ucrainica | (S.Y. Kondr.) S.Y. Kondr. et al. (2012) | No | Polycauliona ucrainica | 950 | LC | ||||
| 5243 | Megalaria grossa | (Pers. ex Nyl.) Hafellner (1984) | Yes | Megalaria grossa | Catillaria grossa Catinaria grossa |
323 | LC | Megalaria grossa | ||
| 5244 | Megalaria laureri | (Hepp ex Th. Fr.) Hafellner (1993) | Yes | Megalaria laureri | Catinaria laureri | 324 | EN D NR P Eng S8 IR | Megalaria laureri | ||
| 5245 | Megalaria pulverea | (Borrer) Hafellner & E. Schreiner (1992) | Yes | Megalaria pulverea | Catillaria pulverea | 318 | LC | Megalaria pulverea | ||
| 5246 | Megalospora fucata | (Stirt.) H. Olivier | No | Violella fucata | 908 | LC | ||||
| 5247 | Megalospora pachycarpa | (Delise ex Duby) H. Olivier | No | Megalospora tuberculosa | 862 | currently a synonym but may be adopted as the correct name in the future | NT NS P Eng Sc Wa IR | |||
| 5248 | Megalospora tuberculosa | (Fée) Sipman (1983) | Yes | Megalospora tuberculosa | Bombyliospora pachycarpa | 862 | NT NS P Eng Sc Wa IR | Megalospora tuberculosa | ||
| 5249 | Megaspora verrucosa | (Ach.) Arcadia & A. Nordin (2012) | Yes | Megaspora verrucosa | Aspicilia verrucosaLecanora verrucosaPachyospora verrucosa | 971 | NT NS | Megaspora verrucosa | ||
| 5250 | Melanaria lactescens | (Mudd) Erichsen | No | Pertusaria lactescens | 1078 | LC |