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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 9031 | Xanthoria polycarpa | (Hoffm.) Th. Fr. ex Rieber (1891) | No | Polycauliona polycarpa | 1531 | LC | ||||
| 9032 | Xanthoria polycarpa f. lobulata | auct. brit. | No | Polycauliona polycarpa | 1531 | LC | ||||
| 9033 | Xanthoria ucrainica | S.Y. Kondr. (1997) | No | Polycauliona ucrainica | 950 | considered by some to be broad-lobed morph of X. candelaria | LC NS | |||
| 9034 | Xanthoria ulophyllodes | Räsänen (1931) | No | Xanthomendoza ulophyllodes | 1909 | LC NS | ||||
| 9035 | Xanthoriicola physciae | (Kalchbr.) D. Hawksw. (1973) | Yes | Xanthoriicola physciae | 2272 | LC | LF | Xanthoriicola physciae | ||
| 9036 | Xanthosyne varians subsp. exigua | (Chaub.) Brodo, López de Silanes, Lendemer, R.C. Harris & McMullin (2024) | No | Traponora varians | 1769 | may become the accepted name | DD NR | |||
| 9037 | Xenonectriella calabrica | Brackel & Puntillo (2016) | Yes | Xenonectriella calabrica | 2807 | on Pertusaria pertusa | NE NR | LF | Xenonectriella calabrica | |
| 9038 | Xenonectriella fissuriprodiens | (Etayo) Etayo (2017) | Yes | Xenonectriella fissuriprodiens | Pronectria fissuriprodiens | 2172 | on Lobaria pulmonaria | LC NS | LF | Xenonectriella fissuriprodiens |
| 9039 | Xenonectriella leptaleae | (J. Steiner) Rossman & Lowen (1999) | No | Pronectria leptaleae | 2409 | NE NR | LF | |||
| 9040 | Xenonectriella leptaleoides | (Etayo) Etayo (2008) | Yes | Xenonectriella leptaleoides | Pronectria leptaleoides | 2773 | on Leptogium cyanescens | NE NR | LF | Xenonectriella leptaleoides |
| 9041 | Xenonectriella lutescens | (Arnold) Weese (1919) | Yes | Xenonectriella lutescens | 2548 | NE NR | LF | Xenonectriella lutescens | ||
| 9042 | Xenonectriella physciacearum | F. Berger, E. Zimm. & Brackel (2020) | Yes | Xenonectriella physciacearum | 2796 | lichenicolous on Physcia | NE NR | LF | Xenonectriella physciacearum | |
| 9043 | Xenonectriella septemseptata | (Etayo) Etayo & van den Boom (2014) | Yes | Xenonectriella septemseptata | Pronectria septemseptata | 2765 | on Melanelixia subaurifera | NE NR | LF | Xenonectriella septemseptata |
| 9044 | Xenonectriella streimannii | (S.Y. Kondr., Coppins & D.J. Galloway) Rossman (1999) | Yes | Xenonectriella streimannii | Pronectria streimannii | 2367 | NE NR | LF | Xenonectriella streimannii | |
| 9045 | Xenonectriella subimperspicua | (Speg.) Etayo (2017) | Yes | Xenonectriella subimperspicua | Pronectria subimperspicua | 2753 | on Parmelia & Punctelia spp. | NE NR | LF | Xenonectriella subimperspicua |
| 9046 | Xerotrema megalospora | Sherwood & Coppins (1980) | Yes | Xerotrema megalospora | 1960 | NT NR Sc IR | F | Xerotrema megalospora | ||
| 9047 | Xerotrema quercicola | Coppins & Aptroot (2008) | Yes | Xerotrema quercicola | 2518 | NT NR E IR | F | Xerotrema quercicola | ||
| 9048 | Xylographa abietina | (Pers.) Zahlbr. | No | Xylographa parallela | 1532 | LC | ||||
| 9049 | Xylographa andrewii | (Stirt.) Reding. (1938) | No | Geltingia associata | 1943 | LC NS | LF | |||
| 9050 | Xylographa corrugans | Norman | No | Xylographa vitiligo | 1534 | LC | ||||
| 9051 | Xylographa laricicola | Nyl. | No | Xylographa parallela | 1532 | LC | ||||
| 9052 | Xylographa minutula | Körb. | No | ? Xylographa parallela | ||||||
| 9053 | Xylographa parallela | (Ach.) Fr. (1849) | Yes | Xylographa parallela | Xylographa abietina | 1532 | LC | Xylographa parallela | ||
| 9054 | Xylographa parallela f. alliptica | Nyl. ex Cromb. [orth. error] | No | Xylographa parallela | 1532 | LC | ||||
| 9055 | Xylographa parallela f. elliptica | Nyl. (1879) | No | Xylographa parallela | 1532 | LC | ||||
| 9056 | Xylographa rubescens | Räsänen (1921) | Yes | Xylographa rubescens | 2808 | NE NR | Xylographa rubescens | |||
| 9057 | Xylographa spilomatica | (Anzi) Th. Fr. | No | Xylographa vitiligo | 1534 | LC | ||||
| 9058 | Xylographa trunciseda | (Th. Fr.) Minks ex Redinger (1938) | Yes | Xylographa trunciseda | 1533 | LC NS | Xylographa trunciseda | |||
| 9059 | Xylographa vitiligo | (Ach.) J.R. Laundon (1963) | Yes | Xylographa vitiligo | 1534 | LC | Xylographa vitiligo | |||
| 9060 | Xylohyphopsis xanthoriicola | Pinault & Diederich (2024) | Yes | Xylohyphopsis xanthoriicola | 2902 | on Xanthoria parietina | NE NR | Xylohyphopsis xanthoriicola |