Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Vegetative hyphae: brown, torulose, branched and anastomosed, 4-6 µm in diam., forming a superficial reticulum on the host thallus, BCr- Pseudothecia: black, sessile, globose to subglobose, 25-35(-40) µm in diam. wall: upper and lower part brown, composed by 1-2 cell layers, mostly 5-10 µm thick, hyphae 3-4 µm wide and 4-5 µm long hamathecium: without paraphysoids and periphyses asci: bitunicate, fissitunicate, broadly saccate, sessile, 16-20 x 8-9 µm, 8-spored; epiplasma: in young asci I+ orange (dextrinoid reaction), with an ocular chamber ascospores: brown, 1-septate, cells of equal size, not or slightly constricted at the septa, ellipsoid, (6.5-)7.5-8(-8.5) Pycnidia: not observed. Host: on the thallus and apothecia of Teloschistes chrysophthalmus World and Sonoran distribution: known from Baja California Sur. Notes: This Sphaerellothecium species has the smallest pseudothecia and ascospores within the genus.