Based on the fulfillment of reciprocal monophyly andobserved genealogical concordance under the genealogical concordance phylogenetic speciesrecognition, we determined that the Globisporangium ultimum species complex is composed offour genetically distinct species: Globisporangium ultimum, Globisporangium sporangiiferum,Globisporangium solveigiae, and Globisporangium bothae.

Aside from cardinal temperatures,we were unable to find any other significant morpholo-gical, physiological, pathological, geographic, or hostpreference that would distinguish between these fournewly identified species. The described morphologicalcharacteristics and plates from Trow (1901), Drechsler(1960), and Van der Plaats-Niterink (1981) remain useful in broadly describing the morphology of this complex, even if they cannot be used diagnostically todifferentiate the four species.