Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Habit: lichenized or lichenicolous Thallus: crustose, immersed to superficial, often evanescent or scarcely apparent photobiont: primary one usually Trentepohlia but sometimes a chlorococcoid green alga, or absent; secondary one absent Ascomata: apothecial, immersed to superficial, +rounded to elongated and lirelliform, sometimes branched disc: exposed or slit-like, black exciple: prosoplectenchymatous, indistinct to well developed and continuous below the hymenium, or sometimes stipe-like, dark brown to black epihymenium: usually dark brown hymenium: colorless or brown-striate, I- or I+ blue; paraphyses: thread-like, simple to sparsely branched or anastomosed, mostly free; hypothecium: colorless to brown asci: elongate-clavate, generally thickened at the apex, usually with I-, K/I- apical dome and with an internal ocular chamber ascospores: hyaline at first, often +distinctly brown and smooth to warty at maturity, usually 1-septate (rarely to 5-7-septate), ellipsoid to sole-shaped, thin-walled, the cells not lens-shaped, N- Conidiomata: pycnidial conidia: long Secondary metabolites: thallus usually without secondary metabolites, rarely with an unidentified pigment Substrate: on bark, more rarely rock, or other lichens Geography: best developed in tropical regions, but occasionally in temperate regions. Notes: The generic name Melaspilea has been traditionally employed for crustose lichens with lirelliform apothecia and brown, 1-septate ascospores. The generally accepted type species appears to be close to Buellia. The genus as currently recognized is very heterogeneous and in need of a thorough revision.