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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 391 | Arthonia protoparmeliae | Etayo (2010) | Yes | Arthonia protoparmeliae | 2655 | lichenicolous on Protoparmelia badia | NE NR | LF | Arthonia protoparmeliae | |
| 392 | Arthonia protoparmeliopseos | Etayo & Diederich (2009), orth. error | No | Arthonia protoparmeliopsidis | 2631 | NE NR | LF | |||
| 393 | Arthonia protoparmeliopsidis | Etayo & Diederich (2009) | Yes | Arthonia protoparmeliopsidis | Arthonia protoparmeliopseos | 2631 | on apothecia and thallus of Protoparmeliopsis muralis | NE NR | LF | Arthonia protoparmeliopsidis |
| 394 | Arthonia pruinata | (Pers.) Steud. ex A.L. Sm. (1911) | No | Pachnolepia pruinata | 63 | LC | ||||
| 395 | Arthonia punctella | Nyl. (1859) | Yes | Arthonia punctella | 1929 | lichenicolous on Diplotomma alboatrum | LC NR | LF | Arthonia punctella | |
| 396 | Arthonia punctiformis | Ach. (1808) | No | Naevia punctiformis | 68 | LC | F | |||
| 397 | Arthonia punctiformis var. melantera | sensu Leight. | No | Naevia punctiformis | 68 | LC | F | |||
| 398 | Arthonia punctilliformis | Leight. | No | of uncertain affinity | F | |||||
| 399 | Arthonia punctilliformis | Leight. (1876) | Yes | Arthonia punctilliformis | 2010 | NE NR | F | Arthonia punctilliformis | ||
| 400 | Arthonia radiata | (Pers.) Ach. (1808) | Yes | Arthonia radiata | Arthonia radiata var. swartziana | 69 | LC | Arthonia radiata | ||
| 401 | Arthonia radiata var. swartziana | (Ach.) P. Syd. | No | Arthonia radiata | 69 | LC | ||||
| 402 | Arthonia reniformis | (Pers.) Röhl. (1813) | Arthonia reniformis | Incorrectly reported from the British Isles | ||||||
| 403 | Arthonia ruana | A. Massal. (1852) | No | Arthothelium ruanum | 97 | LC NS | ||||
| 404 | Arthonia sampaianae | (Diederich & Etayo) Ertz & Diederich (2005) | Yes | Arthonia sampaianae | Plectocarpon sampaianae | 2154 | lichenicolous on Fuscopannaria sampaiana | NT NR | LF | Arthonia sampaianae |
| 405 | Arthonia spadicea | Leight. (1854) | No | Diarthonis spadicea | 70 | LC | ||||
| 406 | Arthonia stellaris | auct. brit. p.p., non Kremp. | No | Synarthonia astroidestera | 1687 | name or specific epithet valid but has been misused in the past | NT NS IR | |||
| 407 | Arthonia stellaris | Kremp. (1861) | Yes | Arthonia stellaris | 71 | LC NS | Arthonia stellaris | |||
| 408 | Arthonia stereocaulina | (Ohlert) R. Sant. (1993) | Yes | Arthonia stereocaulina | 2406 | lichenicolous on Stereocaulon | DD NR | LF | Arthonia stereocaulina | |
| 409 | Arthonia stictarum | (Tul.) Th. Fr. | No | Plectocarpon lichenum | 2153 | LC NS | LF | |||
| 410 | Arthonia subastroidea subsp. orbilliferum | Almq. (1880) | No | Arthothelium orbilliferum | 1711 | LC NS Sc IR | F | |||
| 411 | Arthonia subfuscicola | (Linds.) Triebel (1991) | Yes | Arthonia subfuscicola | 1936 | lichenicolous on Lecanora carpinea | NE NR Sc | LF | Arthonia subfuscicola | |
| 412 | Arthonia substellaris | Coppins in sched. | No | Reichlingia anombrophila | 1588 | LC NS Sc IR | ||||
| 413 | Arthonia subvarians | Nyl. | No | Arthonia apotheciorum | 1501 | LC NS | LF | |||
| 414 | Arthonia swartziana | Ach. | No | Arthonia radiata | 69 | LC | ||||
| 415 | Arthonia thelotrematis | Coppins (1989) | Yes | Arthonia thelotrematis | 1937 | lichenicolous on Thelotrema lepadinum | LC NR Sc IR | LF | Arthonia thelotrematis | |
| 416 | Arthonia thoriana | Ertz & Sanderson (2018) | Yes | Arthonia thoriana | 2714 | NE NR | F | Arthonia thoriana | ||
| 417 | Arthonia tumida agg. | No | 1568 | BLS number no longer used | ||||||
| 418 | Arthonia tumidula | (Ach.) Ach. (1806) | No | Coniocarpon cinnabarinum | 72 | LC | ||||
| 419 | Arthonia varia | (Tul.) Jatta (1900) | No | Phacothecium varium | 1953 | LC NR | LF | |||
| 420 | Arthonia varians | (Davies) Nyl. (1861) | Yes | Arthonia varians | Arthonia glaucomaria | 714 | LC NS | LF | Arthonia varians |