I have been fishing with my father since I was 5.
Occasionally we would find what he called "Doctors".
These strange creatures often lived with the gill space of a fish.
I was always led to believe that they were parasitic, though helpful, to their host.
Below is pictured the creature in question.
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This specimen was the largest I had ever seen, measuring over 25mm head to tail.
The multitude of appendages makes it most unusual indeed.
It was found within the innards of its host, a Leather-jacket, whilst I was cleaning my catch from a fishing trip.
I would welcome any input on this strange creature.