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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 8341 | Thrombium laetevirens | A.L. Sm. (1911) | No | Wahlenbergiella mucosa | 1506 | LC | ||||
| 8342 | Thrombium thelostomum | (Ach. ex J. Harriman) A.L. Sm. | No | Pyrenocarpon thelostomum | 1813 | DD NR | ||||
| 8343 | Thyrea radiata | (Sommerf.) Zahlbr. | No | Lempholemma radiatum | 818 | NT NR Sc | ||||
| 8344 | Tichothecium calcaricola | (Mudd) Arnold (1874) | No | Endococcus rugulosus | 2061 | NE NR | LF | |||
| 8345 | Tichothecium cerinarium | (Mudd) Berl & Voglino | No | ? Lichenodiplis lecanorae {LF} | LF | |||||
| 8346 | Tichothecium erraticum | A. Massal. | No | Muellerella lichenicola | 2116 | LC | LF | |||
| 8347 | Tichothecium gemmiferum | auct. | No | Endococcus propinquus | 2060 | LC NS | LF | |||
| 8348 | Tichothecium lichenicola | (Sommerf.) R. Sant. (1960) | No | Muellerella lichenicola | 2116 | LC | LF | |||
| 8349 | Tichothecium perpusillum | (Nyl.) Arnold (1874) | No | Endococcus perpusillus | 2059 | NE NR | LF | |||
| 8350 | Tichothecium pygmaeum | Körb. | No | Muellerella pygmaea | 2118 | LC | LF | |||
| 8351 | Tichothecium pygmaeum var. ecatonosporum | (Anzi) G. Winter | No | Muellerella pygmaea | 2118 | LC | LF | |||
| 8352 | Tichothecium pygmaeum var. erraticum | (A. Massal.) Vouaux | No | Muellerella lichenicola | 2116 | LC | LF | |||
| 8353 | Tichothecium pygmaeum var. ventosicola | (Mudd) G. Winter | No | Muellerella ventosicola | 2120 | NE NR | LF | |||
| 8354 | Tichothecium rimosicola | (Leight.) Arnold (1861) | No | Phaeospora rimosicola | 2142 | LC NR | LF | |||
| 8355 | Tichothecium rugulosum | (Nyl.) Arnold | No | Endococcus rugulosus | 2061 | NE NR | LF | |||
| 8356 | Tichothecium squamarioides | (Mudd) G. Winter | No | Polycoccum squamarioides | 2168 | NE NR | LF | |||
| 8357 | Tichothecium stereocaulicola | (Linds.) Arnold | No | Polycoccum trypethelioides | 2169 | NT NR | LF | |||
| 8358 | Tichothecium stigma | auct. | No | Endococcus perpusillus | 2059 | NE NR | LF | |||
| 8359 | Tichothecium vermicularium | (Linds.) Arnold | No | incorrectly reported from the British Isles | LF | |||||
| 8360 | Tingiopsidium elaeinum | (Wahlenb.) Hafellner & T. Sprib. (2016) | Yes | Tingiopsidium elaeinum | Vestergrenopsis elaeina | 1822 | VU D2 NR Sc | Tingiopsidium elaeinum | ||
| 8361 | Toensbergia geminipara | (Th. Fr.) T. Sprib. & Resl (2020) | Yes | Toensbergia geminipara | Ochrolechia geminipara; Pertusaria geminipara | 923 | NT NR Sc | Toensbergia geminipara | ||
| 8362 | Toensbergia leucococca | (R. Sant.) Bendiksby & Timdal (2013) | Yes | Toensbergia leucococca | Hypocenomyce leucococca; Pycnora leucococca | 1868 | DD NR Sc | Toensbergia leucococca | ||
| 8363 | Tomasellia diffusa | (Leight.) J. Lahm (1885) | Yes | Tomasellia diffusa | Melanotheca diffusa | 1730 | LC NR Sc | F | Tomasellia diffusa | |
| 8364 | Tomasellia gelatinosa | (Chevall.) Zahlbr. (1922) | Yes | Tomasellia gelatinosa | Melanotheca gelatinosa | 1565 | LC | F | Tomasellia gelatinosa | |
| 8365 | Tomasellia ischnobela | (Nyl.) Keissl. | No | Celothelium ischnobelum | 1566 | LC | ||||
| 8366 | Tomasellia lactea | (Ach.) R.C. Harris | No | Mycoporum lacteum | 1576 | NT NS Sc | F | |||
| 8367 | Toninia alutacea | (Anzi) H. Olivier | No | incorrectly reported from the British Isles | ||||||
| 8368 | Toninia aromatica | (Sm.) A. Massal. (1855) | No | Toniniopsis aromatica | 1415 | LC | ||||
| 8369 | Toninia caeruleonigricans | auct. | No | Thalloidima sedifolium | 1416 | LC P Eng Wa | ||||
| 8370 | Toninia cambrica | (Wheldon) Walt. Watson | No | Stereocaulon leucophaeopsis | 1639 | LC NS M* |