Caulobacter

What you should know:

Caulobacter is a Gram-negative appendaged bacterium with an unusual life cycle. It lives in aquatic habitats and reproduces when one cell attaches itself to a surface and divides (by fission), producing a motile (flagellated) swarmer cell.

Classification: 

Domain Bacteria

    Phylum Proteobacteria

        Class a - Proteobacteria 

Bergey's Manual Volume 2: The Proteobacteria