Final answer:
There are resources, such as Systema Naturae and Bergey's Manual of Determinative Bacteriology, which detail the defining features of each taxa.
Step-by-step explanation:
There are resources available that detail the defining features of each taxa. One such resource is the Systema Naturae, which is a standard resource for identifying bacteria. Another resource is Bergey's Manual of Determinative Bacteriology, which provides information about named species and a framework for adding new species. These resources can be consulted to learn about the defining features of different taxa.