I recall the work 'Omnivore' (cannot be sure of the author after 40 years, but I think it was Harry Harrison. It was of the Golden Age of Science Fiction, and that genre of authors, like Keith Laumer, Asimov, Ben Bova, John Campbell, Zelazny, Poulson, Dick, and the like), which was jacketed with a marvelous painting of a one limbed, hopping, cyclopian fungus that ruled some planet or other.
Enjoy!