Two clades designated BCG2 and GS2 are believed to be the sister clades of this taxon. Revised nomenclature for this taxon where each member has only one name was introduced in 2011, since many species of this taxon confusingly have two distinct names. Fossils with right-angle branching thought to be an early terrestrial member of this taxon, Ourasphaira giraldae, were discovered in the Arctic in 2019. The universal barcode for DNA barcoding of this taxon is internal transcribed (*) spacer DNA. Historically, organisms (10[1])in this kingdom without a known sexual teleomorph stage were classified into an informal subtaxon called [this kingdom] imperfecti. Both animals and this kingdom are opisthokonts, meaning this kingdom is the kingdom most closely related to (10[1])Animalia. Ascomycota and basidiomycota are phyla in, for 10 points, what kingdom of organisms characterized by chitinous cell walls and spore formation? ■END■