Relating to or characteristic of a cercaria or cercariae; describing features of the tail-bearing larval stage of parasitic flatworms.
From cercaria plus the suffix -al. This adjective form allows scientists to describe traits specific to this larval stage.
When parasitologists describe how dangerous a parasite is, they often focus on the 'cercarial stage' because that's when the creature can actually hunt you—once it matures, it's trapped inside a host, but as a cercaria, it's free and hunting.
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