Which bugs are present in diesel?

The organisms currently most frequently found in diesel fuel include moulds, yeasts and bacteria. The main mould is Hormoconis resinae, the main yeasts are Yarrowia Lipolytica & Candida Kerosenii and the most common bacterium is Pseudomonas Aeriginosa. These organisms are believed to work as a consortium known as the diesel bug, living in the moisture generated by condensation and feeding off the alkanes in the fuel. As may be expected from fast reproducing organisms, new variants are always potentially evolving.