We often find these beautiful and fascinating orange-colored colonies growing on agar plates that keep lying at 4 degrees for long. This is either Micrococcus sp. (most probably M. roseus) or Serratia sp. In most cases, Micrococcus sp. is the one contaminating the solid medium.
Macarena Lucia Fernandez Carro, bacteria are indeed beautiful. Their alluring and vibrant pigments make them soo captivating. Well, that's the beauty of nature :)