does it have any uses?
Yes, to bioaccumulate cadmium; and as a biocatalyst.
Marasmius rotula
The fruit bodies will bioaccumulate cadmium: a study of the metal concentration of 15 wild mushroom species of India showed that "M. rotula" accumulated the highest concentration of that metal.

A peroxidase enzyme known as "Mro"APO ("Marasmius rotula" aromatic peroxygenase) is attracting research interest for possible applications in biocatalysis. 
what is the marasmius rotula? A common species of agaric fungus
wiki:24301341
Marasmius rotula [SEP] Uses
In general, enzymes that catalyze oxygen-transfer reactions are of great utility in chemical synthesis since they work selectively and under ambient conditions. Fungal peroxidases can catalyze oxidations that are difficult for the organic chemist, including those involving aromatic substrates such as aniline, 4-aminophenol, hydroquinone, resorcinol, catechol, and paracetamol. The "M. rotula" enzyme is the first fungal peroxygenase that can be produced in high yields. It is highly stable over a wide pH range, and in a variety of organic solvents. The enzyme has other potential for use as a biosensor for aromatic substances in environmental analysis and drug monitoring.