[<< wikibooks] Dichotomous Key/Bacteria
Include the cyanobacteria (autotrophic) and eubacteria (heterotrophic).

Acidobacteria (acidophilic, gram positive, high G+C, common in dirt)
Actinobacteria (high G+C gram positive bacteria)
Aquificae (hyperthermophilic chemolithoautotrophs, gram negative)
Bacteroidetes (really diverse group with pathogens, commensals, and free-living bacteria; anaerobic, gram negative, rod shaped)
Chlamydiae (obligate intracellular parasites of eukaryotic cells, gram negative)
Chlorobi (anaerobic, photoautotrophic, gram negative green sulfur bacteria)
Chloroflexi (greeen nonsulfur bacteria)
Chrysiogenetes (chemolithoautotrophic bacterium)
Cyanobacteria (oxygenic photosynthetic bacteria and chloroplasts)
Deferribacteres (aquatic, anaerobic bacteria)
Deinococcus-Thermus (extremophiles, gram negative)
Dictyoglomi (thermophilic chemoorganotrophs)
Fibrobacteres (cellulose digesting, anaerobic rumen bacteria, two species)
Firmicutes (low G+C gram positives)
Fusobacteria (obligate anaerobic heterotrophs, many involved in human infections, gram negative, non-spore forming)
Gemmatimonadetes (Gram negative bacteria lacking DAP in cellular envelopes)
Nitrospira (gram negative; includes nitrite-oxicizers, thermophilic sulfate reducers, and acidophilic iron reducers)
Planctomycetes (ovoid gram negative bacteria, reproduce by budding)
Proteobacteria (purple bacteria and relatives, gram negative)
Spirochaetes (spiral-shaped chemoheterotrophs, gram negative)
Synergistetes (gram negative, rod/vibroid cell shape)
Tenericutes (gram positive, no cell wall)
Thermodesulfobacteria (thermophilic, sulfate-reducing bacteria)
Thermomicrobia (hyperthermophilic chemoheterotrophs)
Thermotogae (hyperthermophilic, obligate anaerobic, fermentive heterotrophs)
Verrucomicrobia (terrestrial, aquatic, some associated with eukaryotic hosts; gram negative)