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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 4801 | Leptotrema monosporum | auct. brit., non (Nyl.) Müll. Arg. | No | Thelotrema macrosporum | 1411 | LC NS Sc IR | ||||
| 4802 | Letharia arenaria | auct. brit. | No | Evernia prunastri | 511 | LC | ||||
| 4803 | Lettauia cladoniicola | D. Hawksw. & R. Sant. (1990) | No | Cryptodiscus cladoniicola | 2084 | NE NR | LF | |||
| 4804 | Leucocarpia biatorella | (Arnold) Vězda (1969) | No | Psoroglaena biatorella | 1774 | DD NR Sc | ||||
| 4805 | Leucocarpopsis devensis | G. Salisb. (1975) | No | Verrucaria devensis | 850 | NE NR | ||||
| 4806 | Leucodecton isidioides | (Borrer) Lücking & Breuss (2012) | Yes | Leucodecton isidioides | Thelotrema isidioides | 1409 | NE (Ireland only) | Leucodecton isidioides | ||
| 4807 | Leucodermia leucomelos | (L.) Kalb (2015) | No | Heterodermia leucomelos | 558 | EN C2 NR P Eng Wa S8 IR | ||||
| 4808 | Leucogyrophana lichenicola | Thorn, Malloch & Ginns (1998) | No | Penttilamyces lichenicola | 2627 | NE NR | LF | |||
| 4809 | Libertiella malmedyensis | Speg. & Roum. (1880) | Yes | Libertiella malmedyensis | 2085 | NE ? | LF | Libertiella malmedyensis | ||
| 4810 | Libertiella peltigerae | (Lib. ex Cooke) Keissl. | No | Libertiella malmedyensis | 2085 | NE ? | LF | |||
| 4811 | Lichen abietinus | sensu Sm. (1807), non Ach. | No | Cresponea premnea | 605 | LC Sc IR | ||||
| 4812 | Lichen abietinus | Ach. | No | Lecanactis abietina | 592 | LC | ||||
| 4813 | Lichen acicularis | sensu Sm., non Ach. | No | Chaenotheca hispidula | 345 | LC NS | ||||
| 4814 | Lichen aculeatus | Schreb. | No | Cetraria aculeata | 430 | LC | ||||
| 4815 | Lichen aculeatus | With. | No | Cetraria aculeata | 430 | LC | ||||
| 4816 | Lichen affinis | Dicks. | No | Pannaria rubiginosa | 980 | LC Sc L IR | ||||
| 4817 | Lichen agelaeus | Ach. | No | Phlyctis agelaea | 1109 | NT NS Sc | ||||
| 4818 | Lichen albellus | Pers. | No | Lecanora albella | 754 | LC NS Sc | ||||
| 4819 | Lichen albescens | Huds. (1762) | No | Lepra albescens var. albescens | 1056 | LC | ||||
| 4820 | Lichen alcicornis | Lightf. (1777) | No | Cladonia foliacea | 387 | LC | ||||
| 4821 | Lichen amphibius | With. | No | ? Dermatocarpon luridum | ||||||
| 4822 | Lichen ampullaceus | L. | No | Parmelia omphalodes | 1006 | LC | ||||
| 4823 | Lichen anthracinus | Wulfen | No | Umbilicaria polyphylla | 1451 | LC | ||||
| 4824 | Lichen aquaticus | L. | No | Dermatocarpon luridum | 487 | LC | ||||
| 4825 | Lichen aquaticus | Weiss, non L. | No | Dermatocarpon luridum | 487 | LC | ||||
| 4826 | Lichen aromaticus | Sm. | No | Toninia aromatica | 1415 | LC | ||||
| 4827 | Lichen articulatus | L. | No | Usnea articulata | 1456 | NT P Eng Wa IR | ||||
| 4828 | Lichen atlanticus | Sm. | No | Tornabea scutellifera | 1430 | Ex | ||||
| 4829 | Lichen atratus | Sm. (1811), non Hedw. (1788) | No | Orphniospora moriopsis var. moriopsis | 969 | LC NS | ||||
| 4830 | Lichen atrocinereus | Dicks. (1793), non Vill. (1789) | No | Rinodina atrocinerea | 1281 | LC |