Bactrospora flavopruinosa

Bactrospora flavopruinosa, the dead cedar lichen, is a species of lignicolous (wood-dwelling) lichen of uncertain familial placement in the Arthoniales. Found in Bermuda, it was described as a new species in 2008. It forms thin, mostly hidden crusts on barkless Bermuda cedar wood, showing only as whitish patches with scattered yellow dots from its algal cells. The species is distinctive for its bright lemon-yellow, powdery fruiting bodies that contrast sharply with the black margins typical of related species, combined with exceptionally narrow, thread-like ascospores that do not fragment. It is known only from the Walsingham Nature Reserve in Bermuda, where it grows on the persistent dead trunks of Bermuda cedar trees killed by a twentieth-century scale insect outbreak, and forms part of a specialised community of wood- and bark-inhabiting lichens restricted to this habitat....read more on Wikipedia.