Catawba Everniastrum Lichen 
Catkin cup 
Cellar Cup 
Chicken lips 
Chlorencoelia versiformis 
Chlorosplenium chlora 
Christmas Fern Leaf Curl 
Christmas Lichen 
Chromelosporiopsis coerulescens 
Chrysothrix caesia 
Chrysothrix xanthina 
Cinder Lichen 
Citrus Green Mold 
Cladia retipora 
Coal fungus 
Coccomyces dentatus 
Coccomyces triangularis 
Comet Spored Lichen 
Common Brown Cup 
Common button lichen 
Common Cladia 
Common Greenshield Lichen 
Common Powderhorn 
Common Sunburst Lichen