''Chaenothecopsis polissica'' is a species of fossilized

pin lichen Lichens are wikt:composite, composite organisms made up of multiple species: a fungus, fungal partner, one or more photosynthetic partners, and sometimes a yeast, basidiomycete yeast. They are regularly grouped by their external appearance – a c ...

in the family

Mycocaliciaceae The Mycocaliciaceae are a family (biology), family of seven genus, genera and about 90 species of fungi in the order Mycocaliciales. Taxonomy Calicioid fungi are a heterogeneous assemblage of fungi sharing the presence of a mazaedium, a structur ...

that was discovered in 2021 by Vasyl Heluta and Maryna Sukhomlyn. The holotype was recovered from

Rovno amber Rivne amber, occasionally called Ukrainian amber, is amber found in the Rivne Oblast and surrounding regions of Ukraine and Belarus. The amber is dated between Late Eocene and Early Miocene, and suggested to be contemporaneous to Baltic amber. ...

, which formed in the Ukraine during the late Eocene.

References

Lichen species Lichens described in 2021 Lichens of Eastern Europe Prehistoric fungi Eurotiomycetes {{Eurotiomycetes-stub