Type: USA. Arkansas. Searcy Co.: Buffalo National River, Tyler Bend along River View Trail from Collier Homestead Trailhead, 35°58'31"N, 92°45'56"W, dolomite bluffs in hardwood forest, on vertical dolomite bluff, 17.iv.2005, Buck 48756 (NY, holotype).
Etymology: Phoebus = Greek sun god, hydrophobius = water fearing, for its ecological preference
Distribution and ecology: Restricted to massive calcareous substrates, typically on vertical faces of dolomite and limestone in areas of moderately high light intensity but protected from wetting.
- Harris, R.C. and Ladd, D. (2007) New taxa of lichens and lichenicolous fungi from the Ozark Ecoregion. Opuscula Philolichenum 4: 57–68. (Web site) (Duke edu) (Discussion of Phoebus hydrophobius: pp. 64-65; color photos: p. 63, Plate 3, Figs. 1-9)