Acanthotrema alboisidiatum

Acanthotrema alboisidiatum is a species of corticolous (bark-dwelling) crustose lichen in the family Graphidaceae. Described as a new species in 2014, it is primarily distinguished by its striking white isidia that contrast with its light olive-green thallus. The lichen was recognized as a new species despite the absence of ascomata and ascospores, usually crucial for taxonomic identification. Its DNA sequence data confirms its place in the Acanthotrema genus but distinguishes it from other known members of this genus. The species grows up to a diameter of 5 cm (2 in) and bears short, white isidiate outgrowths that resemble insect eggs. The lichen appears to favour the shaded understory of Tabonuco forests in El Yunque National Forest, Puerto Rico, particularly towards the base of Dacryodes excelsa trees....read more on Wikipedia.