Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: uniform, tightly attached, rimose-areolate areoles: irregularly polygonal, plane, thin, 0.2-1.6 mm in diam. surface: grayish brown to brown, smooth, shiny or dull, epruinose Ascomata: apothecioid, urceolate, sessile, up to 1.3 mm in diam., +round disc: concave, black, slightly pruinose pseudoexciple: black, 70-100 µm thick true exciple: absent hymenium: 90-120 µm tall; paraphyses: simple, flaccid, 1-1.5 µm thick; "hypothecium": hyaline, 10-15 µm thick; asci: cylindrical, 80-110 x 15-30 µm, (1)-2-spored ascospores: hyaline to brown, muriform, broadly ellipsoid, 28-42 x 14-23 µm; transverse septa 5-12; longitudinal septa 2-5 per transverse segment Pycnidia: not seen Spot tests: thallus K-, C-, KC-, P-, UV- Secondary metabolites: none detected Substrate and ecology: on siliceous rocks World distribution: subcosmopolitan, in montane to alpine in arid or semi-arid areas Sonoran distribution: only known from a single collection on Santa Rosa Island, California. Notes: Ingvariella bispora is a saxicolous lichen similar to some Diploschistes spp., but easily distinguished by the asci containing 1-2 large ascospores and its brownish thallus. The species was recently segregated from Dip-pseudoparenchymatous proper exciple, that is replaced by loschistes (Guderley et al. 1997) due to the absence of a pseudoexciple formed by hymenial parts.