• Species: Xanthocarpia crenulatella (Nyl.) Frödén, Arup & Søchting
• Remark: earlier under Caloplaca crenulatella
• Fungus type: lichenized
• Treatment in Estonia: certain

• Species: Xanthocarpia lactea (A. Massal.) A. Massal.
• Remark: earlier under Caloplaca lactea
• Fungus type: lichenized
• Treatment in Estonia: certain

• Species: Xanthomendoza oregana (Gyeln.) Søchting, Kärnefelt & S.Y. Kondr.
• Remark: earlier under Xanthoria oregana
• Fungus type: lichenized
• Treatment in Estonia: certain
• oregoni korpsamblik

• Species: Xanthomendoza fallax (Arnold) Søchting, Kärnefelt & S.Y. Kondr.
• Remark: earlier under Xanthoria fallax
• Fungus type: lichenized
• Treatment in Estonia: certain
• lehtjas korpsamblik

• Species: Xanthomendoza fulva (Hoffm.) Søchting, Kärnefelt & S.Y. Kondr.
• Remark: earlier under Xanthoria fulva
• Fungus type: lichenized
• Treatment in Estonia: certain
• soomusjas korpsamblik

• Species: Xylopsora caradocensis (Nyl.) Bendiksby & Timdal
• Remark: earlier under Hypocenomyce caradocensis
• Fungus type: lichenized
• Treatment in Estonia: certain
• põis-soomussamblik

• Species: Xylopsora friesii (Ach.) Bendiksby & Timdal
• Remark: earlier under Hypocenomyce friesii
• Fungus type: lichenized
• Treatment in Estonia: certain
• Friesi soomussamblik

• Species: Zwackhia sorediifera (P. James) Ertz
• Remark: earlier under Opegrapha sorediifera
• Fungus type: lichenized
• Treatment in Estonia: certain

• Species: Zwackhia viridis (Ach.) Poetsch & Schied.
• Remark: earlier under Opegrapha viridis
• Fungus type: lichenized
• Treatment in Estonia: certain

• Species: Atla wheldonii (Travis) Savic & Tibell
• Remark:
• Fungus type: lichenized
• Treatment in Estonia: certain

• Species:
• Remark:
• Fungus type:
• Treatment in Estonia: