On the 9 June 2023, at Mala, Karkala, Karnataka, India, researchers found Rao’s intermediate golden-backed frog, (Hylarana intermedia) with a rather fetching, fungal companion growing out of it's side
Mycologists identified the fungi as Common Bonnet, part of the Mycena genus, a type of fungi that mostly grows on rotting wood from dead trees, however it has also been discovered to be able to thrive on living plants as well
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The frog appeared to be quite healthy and was not caught, so there's no definitive answer why it was hosting a mushroom, however...
...one of the possibilities is that there is a small piece of woody debris under the skin of the frog after it got lodged in the skin and it has sprouted a mushroom from it....
All info from here and here
All photos by Lohit Y.T. one of the researchers who discovered the frog and co-author of the paper