actinomycete
/ˌæktənoʊˈmaɪsit/
noun
A bacterium of an order that typically has a nonmotile filamentous form. They include the economically important streptomycetes, and were formerly regarded as fungi.
In the composting process, the tissues of carcasses are broken down aerobically by bacteria, fungi, actinomycetes, and protozoa to produce water vapor, carbon dioxide, heat, and a stabilized organic residue.