Astrothelium ultralucens
Astrothelium ultralucens is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. Found in Venezuela, it was formally described as a new species in 2016 by André Aptroot. The type specimen was collected by Harrie Sipman along the Carapo River (, Bolivar) at an elevation of . The lichen has a smooth,  somewhat shiny pale greenish grey thallus that covers an area of up to . Its ascospores are hyaline, spindle-shaped (fusiform) with three septa and dimensions of 105–130 by 35–42 µm. Astrothelium ultralucens contains lichexanthone, a lichen product that causes the pseudostromata and the thallus to fluoresce yellow when lit with a long-wavelength UV light, although the thallus only weakly. References

ultralucens
Lichen species
Lichens described in 2016
Lichens of Venezuela
Taxa named by André Aptroot