TYPE. "Ad truncum arboris in summo monte Doi Sutep, circ. 1675 m s. m." C.C. Hosseus s.n. (= Vainio Herb. no. 02999) (TUR-V).

Description. Lichenized fungus.

Thallus foliose, adnate to appressed. Lobes 1-3 mm wide, dichotomously branched, tips blunt and squarish, axils rounded. Upper surface pale greenish gray, smooth, shiny; vegetative diaspores coarse soredia or schizidia erupting from irregular pustules. Medulla white; photobiont chlorococcoid alga. Lower surface black; rhizines black, forked, abundant, forming a mat under and around lobes. Ascomata lecanorine apothecia with brown disks, rare.

Chemistry. Cortex UV+ bright yellow, K+ yellow, KC-, C-, PD-; medulla K+ brown-red, KC+ deep brown-red, C-, PD-; lichexanthone, lividic acid complex.

Substrate and Habitat. Corticolous on hardwoods, less on conifers, infrequently saxicolous, in humid forests.

Distribution. Pantropical, north into temperate east Asia and North America; in North Carolina throughout.

Literature

Brodo, I.M., S. D. Sharnoff & S. Sharnoff. (2001) Lichens of North America. Yale University Press, New Haven & London. 795 pp.

Lendemer, J. & N. Noell. (2018) Delmarva Lichens: An Illustrated Manual. Memoirs of the Torrey Botanical Society 28: 1–350.

Park, Y.S. & M.E. Hale. (1989) Hypotrachyna osseoalba, the correct name for Hypotrachyna formosana (Parmeliaceae: lichenized Ascomycotina). Taxon 38(1): 88.