Organisms having a complex life cycle similar to the animal pathogen Dermatophilus congolensis have been isolated from soils of the United States. The soil isolates grow readily on agar media producing a black, friable, or sooty colony; in broth, the isolates produce a thick sediment with a clear supernatant fluid and occasionally a black surface pellicle. The generic taxon Geodermatophilus is ...

Physiological characteristics play a dominant role in characterization, classification, and speciation of procaryotes. Because of limited morphological diversity, conventional systematics of these microorganisms still is in a disappointing state. Fortunately, with many Actinomycetales morphological diversity does occur. This diversity can be used to advantage in systematics because it represent...