Word for a parasite except that it has no effect on the host
Solution 1:
A host/commensal relationship.
Commensalism:
is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed.
Composed of the two:
The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected.
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