Anamorph: no information available.
Teleomorph: ascomata apothecia, 350-500 µm diam. and ca 100 µm tall, scattered or gregarious, sometimes confluent, superficial, sessile, shallowly pulvinate, lemon yellow, dotted with the protruding tips of ripe asci. Excipule thin and evanescent, not clearly distinguishable from the hymenium. Interascal tissue of unbranched paraphyses 3-4 µm diam., slightly swollen at the apices, the contents yellow. Asci 100-130 x 20-33 µm at maturity, broadly clavate with a short tapered stalk, the apex truncate, operculate, staining blue in iodine, 8-spored. Spore-clusters 43-50 x 14-17 µm, the spores initially free and then loosely clustered, cemented together but quite easily separating with moderate pressure, surrounded by a gelatinous sheath 4-5 µm in thickness. Ascospores 17-19.5 x 8-9 µm, fusiform-ellipsoidal to ± angular in outline, the apices truncate, initially colourless but becoming purple and then brownish when fully mature, shallowly and irregularly verrucose, sometimes appearing weakly reticulate, smooth in areas of contact with other spores, the pigmented layer sometimes sloughing off at maturity.
Some populations have spore clusters that may break apart quite easily, and thus appear similar to Saccobolus saccoboloides (not definitely recorded from GBI). That has ascospores without the characteristic truncate apices seen in S. citrinus.
Saccobolus minimus is very similar, but has much smaller ascospores.
On dung of various herbivores, includding cow, deer, rabbit and sheep.
Throughout Britain, quite common.