Filamentous lichen
From Infogalactic: the planetary knowledge core
A filamentous lichen is a lichen that has a growth form like a mass of thin, stringy, non-branching hairs or filaments.[1][2] Filaments of the photosynthetic partner (Trentepohlia ) or trichome-forming (cyanobacteria) are surrounded by sheaths of the fungal filaments.[2] So unlike in most other lichen growth forms, the filaments of fungus do not determine the shape.[2] Filamentous lichens may look like matted black hair.[2]
