Thermoproteati

Thermoproteati is a kingdom of archaea. Its synonym, "TACK", is an acronym for "Thaumarchaeota" (now Nitrososphaerota), "Aigarchaeota", "Crenarchaeota (now Thermoproteota), and "Korarchaeota", the first groups discovered. They are found in different environments ranging from acidophilic thermophiles to mesophiles and psychrophiles and with different types of metabolism, predominantly anaerobic and chemosynthetic. Thermoproteati is a kingdom that is sister to the "Asgard" branch that gave rise to the eukaryotes. It has been proposed that the Thermoproteati kingdom be classified as "Crenarchaeota" and that the traditional "Crenarchaeota" (Thermoproteota) be classified as a class called Sulfolobia, along with the other phyla with class rank or order. After including the kingdom category into ICNP, the only validly published name of this group is kingdom Thermoproteati (Guy and Ettema 2024).