Short, simple introduction to these organisms.

Lecture slides discuss the three major phyla (methanogens, halophiles and thermoacidophiles) of this kingdom within the Archaea.

Academic thesis on the unexpected organisms discovered by ribosomal analysis of non-extreme soil and water samples.

Systematic discussion of the various phyla within the Crenarchaea, Euryarchaeota, based on RNA differences.

Summary of research on non-thermophilic Crenarchaea in soil ecology.

Taxonomy browser, with some links.

Research proposal for a study of the ecological functions and implications of CO2 fixation by chemolithoautotrophic alkalithermophilic Crenarchaeota. Includes long list of references.

Comparative analysis of small-subunit ribosomal RNA (SSU rRNA) genes from environmental samples. Includes a tree of the major lineages of Archaea, Bacteria, and Eukarya.

Reports the decoding of the Pyrococcus abyssi, which lives in the intense pressure and temperature of black smoker vents on the seafloor.

Online textbook chapter from the University of Wisconsin, discussing various species and touching on some of the molecular characteristics that separate them from other life forms.