what the title says, should parasite tag be a species tag rather than general tag?

Yes. For the adjective, use symbiosis or symbiotic_relationship instead.

Furrin_Gok said:
Yes. For the adjective, use symbiosis or symbiotic_relationship instead.

Actually, shouldn't it be parasitism by default since TWYS makes it at best difficult to separate them?

Circeus said:
Actually, shouldn't it be parasitism by default since TWYS makes it at best difficult to separate them?

parasitism? Hadn't thought of wording it like that. That said, you can't tell when something is mutually beneficial, but you also cannot tell if it's malevolent. Parasitism is where one organism causes harm to the other to gain benefits, whereas symbiosis is where they both gain benefits.
I like using the more benevolent term in such a case, especially since the benign term is a hugely unknown one: Commensalism, where one organism gains benefits without harming the other.

EDIT: According to Wikipedia:

Symbiosis involves two species living in close proximity and includes relationships that are mutualistic, parasitic, and commensal.

If you look at the Symbiosis page,

The definition of symbiosis has varied among scientists. Some believe symbiosis should only refer to persistent mutualisms, while others believe it should apply to any type of persistent biological interaction (in other words mutualistic, commensalistic, or parasitic). After 130 years of debate, current biology and ecology textbooks now use the latter "de Bary" definition or an even broader definition (where symbiosis means all species interactions), with the restrictive definition no longer used (in other words, symbiosis means mutualism).

Circeus said:
Actually, shouldn't it be parasitism by default since TWYS makes it at best difficult to separate them?

That has a point. Just like how being bipedal or anthromorphic is a characteristic of a creature, so is being a parasite.

For example: a tick is a species but a parasite too.