Field Key to Common Umbilicate Lichens
1a Perithecia present, embedded within thallus and evident as openings dotting upper surface (genus Dermatocarpon)……………………………. 2
1b Perithecia absent; apothecia, if present, saucer-shaped and superficial on the thallus………….. 3
2a Lobes distinct, often widely separated from one another; surface bluish green and dull; typically found on limestone…………. Dermatocarpon muhlenbergii
![](https://ohiomosslichen.org/wp-content/uploads/2021/08/species-Dermatocarpon-muhlenbergii-1-1000x750.jpg)
Dermatocarpom muhlenbergii
2b Lobes massed and overlapping; surface bright green and shiny; on wet acidic rocks…………………………….. Dermatocarpon luridum
![](https://ohiomosslichen.org/wp-content/uploads/2021/08/species-Dermatocarpon-luridum-1-1000x750.jpg)
Dermatocarpon luridum
3a Thallus pustulate above, pitted below.. Lasallia papulosa
![](https://ohiomosslichen.org/wp-content/uploads/2021/08/species-Lasallia-papulosa-1-1000x750.jpg)
Lasalila papulosa
3b Thallus smooth above and below… Umbilicaria mammulata
![](https://ohiomosslichen.org/wp-content/uploads/2021/08/species-Umbilicaria-mammulata-1-1000x750.jpg)
Umbilicaria mammulata