Edwardsiella tarda is characterized as:

Edwardsiella tarda is characterized as motile, which is a key distinguishing feature of this bacterium. This motility allows E. tarda to move through various environments, contributing to its pathogenicity and ability to infect different hosts, particularly in aquatic animals.

In the context of bacteriology, the motility of a microorganism can be assessed using various methods, such as the hanging drop technique or stab cultures in semi-solid media. The ability of E. tarda to move is significant to its identification in laboratory settings and clinical practices, often impacting its behavior in host interactions and contributing to infections.

The other options do not accurately describe Edwardsiella tarda. Understanding its motility is crucial for both diagnostics and treatment approaches when dealing with infections caused by this organism.