Any clown has the capacity to host something other than an anemone, but part of it has to do with whether they were wild caught, captive grown, or captive bred. Wild fish will have the highest likely-hood, with captive grown the next highest, and captive bred having the lowest likely-hood.
Personally, my captive bred ocellaris clown has hosted mushrooms and monti-caps (dunno why the latter), but didn't host a frogspawn like I had hoped.