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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 8881 | Xenonectriella septemseptata | (Etayo) Etayo & van den Boom (2014) | Yes | Xenonectriella septemseptata | Pronectria septemseptata | 2765 | on Melanelixia subaurifera | NE NR | LF | |
| 8882 | Xenonectriella streimannii | (S.Y. Kondr., Coppins & D.J. Galloway) Rossman (1999) | Yes | Xenonectriella streimannii | Pronectria streimannii | 2367 | NE NR | LF | Xenonectriella streimannii | |
| 8883 | Xenonectriella subimperspicua | (Speg.) Etayo (2017) | Yes | Xenonectriella subimperspicua | Pronectria subimperspicua | 2753 | on Parmelia & Punctelia spp. | NE NR | LF | |
| 8884 | Xerotrema megalospora | Sherwood & Coppins (1980) | Yes | Xerotrema megalospora | 1960 | ? | NT NR Sc IR | F | Xerotrema megalospora | |
| 8885 | Xerotrema quercicola | Coppins & Aptroot (2008) | Yes | Xerotrema quercicola | 2518 | NT NR E IR | F | Xerotrema quercicola | ||
| 8886 | Xylographa abietina | (Pers.) Zahlbr. | No | Xylographa parallela | 1532 | LC | ||||
| 8887 | Xylographa andrewii | (Stirt.) Reding. (1938) | No | Geltingia associata | 1943 | LC NS | LF | |||
| 8888 | Xylographa corrugans | Norman | No | Xylographa vitiligo | 1534 | LC | ||||
| 8889 | Xylographa laricicola | Nyl. | No | Xylographa parallela | 1532 | LC | ||||
| 8890 | Xylographa minutula | Körb. | No | ? Xylographa parallela | ||||||
| 8891 | Xylographa parallela | (Ach.) Fr. (1849) | Yes | Xylographa parallela | Xylographa abietina | 1532 | LC | Xylographa parallela | ||
| 8892 | Xylographa parallela f. alliptica | Nyl. ex Cromb. [orth. error] | No | Xylographa parallela | 1532 | LC | ||||
| 8893 | Xylographa parallela f. elliptica | Nyl. (1879) | No | Xylographa parallela | 1532 | LC | ||||
| 8894 | Xylographa rubescens | Räsänen (1921) | Yes | Xylographa rubescens | 2808 | NE NR | ||||
| 8895 | Xylographa spilomatica | (Anzi) Th. Fr. | No | Xylographa vitiligo | 1534 | LC | ||||
| 8896 | Xylographa trunciseda | (Th. Fr.) Minks ex Redinger (1938) | Yes | Xylographa trunciseda | 1533 | LC NS | Xylographa trunciseda | |||
| 8897 | Xylographa vitiligo | (Ach.) J.R. Laundon (1963) | Yes | Xylographa vitiligo | 1534 | LC | Xylographa vitiligo | |||
| 8898 | Xylopsora caradocensis | (Nyl.) Bendiksby & Timdal (2013) | Yes | Xylopsora caradocensis | Bilimbia caradocensis; Hypocenomyce caradocensis; Lecidea acutula; Lecidea caradocensis; Psora acutula; Psora caradocensis; Toninia caradocensis | 576 | LC | Xylopsora caradocensis | ||
| 8899 | Xylopsora friesii | (Ach.) Bendiksby & Timdal (2013) | Yes | Xylopsora friesii | Hypocenomyce friesii; Lecidea friesii; Psora friesii | 577 | LC NS | Xylopsora friesii | ||
| 8900 | Zamenhofia coralloidea | (P. James) Clauzade & Cl. Roux | No | Porina coralloidea | 1172 | LC NS Sc L IR | ||||
| 8901 | Zamenhofia hibernica | (P. James & Swinscow) Clauzade & Cl. Roux | No | Porina hibernica | 1178 | NT NS P Eng WaL IR | ||||
| 8902 | Zamenhofia rosei | (Sérus.) P. James | No | Porina rosei | 1671 | NT NS X IR | ||||
| 8903 | Zevadia peroccidentalis | J.C. David & D. Hawksw. (1995) | Yes | Zevadia peroccidentalis | 2273 | LF | Zevadia peroccidentalis | |||
| 8904 | Zhurbenkoa epicladonia | (Nyl.) Flakus, Etayo, Pérez-Ortega & Rodr. Flakus (2019) | Yes | Zhurbenkoa epicladonia | Arthonia epicladonia; Scutula epicladonia | 2199 | on Cladonia basal squamules | NE NR | LF | Zhurbenkoa epicladonia |
| 8905 | Zignoella slaptonensis | P.F. Cannon (1997) | No | Leptosillia slaptonensis | 2869 | NE NR | F | |||
| 8906 | Zwackhia prosodea | (Ach.) Ertz (2012) | Yes | Zwackhia prosodea | Opegrapha prosodea | 956 | NT NS P Eng Wa IR | Zwackhia prosodea | ||
| 8907 | Zwackhia sorediifera | (P. James) Ertz (2012) | Yes | Zwackhia sorediifera | Opegrapha sorediifera | 962 | LC L* | Zwackhia sorediifera | ||
| 8908 | Zwackhia viridis | (Ach.) Poetsch. & Schied. (1872) | Yes | Zwackhia viridis | Opegrapha viridis | 966 | DD NS | Zwackhia viridis | ||
| 8909 | Zwackhiomyces berengerianus | (Arnold) Grube & Triebel (1990) | Yes | Zwackhiomyces berengerianus | 2274 | NE NR | LF | Zwackhiomyces berengerianus | ||
| 8910 | Zwackhiomyces coepulonus | (Norman) Grube & R. Sant. (1990) | Yes | Zwackhiomyces coepulonus | 2320 | NE NR | LF | Zwackhiomyces coepulonus |