Synchronically, by surface analysis, as if putative *fungo- + -phile, in morphologic parallel with fungiphile as fungi- + -phile; *fungo- is nonstandard, but a putative assertion of it is predictable as something that will periodically arise naturally among speakers by apparent analogy with how hundreds of other ISV combining forms containing o are formed (compare -o-, and compare also lexophile); diachronically, the word fungophile has been independently re-created (and googled) many times by individual speakers and writers, some of whom have used it in capitalized proper noun form to name their own mycophilic endeavors (e.g., as a screenname, website title, or otherwise); but its common noun sense is now incontrovertibly attested many times over, albeit informal and nonstandard.
fungophile (plural fungophiles)