Both light and scanning electron microscopy have been used to investigate the morphology and development of Speerschneidera euploca (Tuck.) Trevisan. This monotypic genus produces lecanoralean apothecia and Lecanora-type asci; the latter negates the assumed relationship to Teloschistes and the Teloschistaceae. The information on morphology, ecology, development and chemistry indicate that the genus is appropriately placed in the Lecanoraceae close to Lecania. S. euploca is found on calcareous outcrops from Missouri southwest to Texas and Mexico. It produces only a brown pigment concentrated in the tips of the paraphyses.