Images were submitted of a fish market of a Poor cod (or Trisopterus minutus capelanus) that presents a parasite attached to the gills.

The image of the parasite is compatible with a copepod, a type of crustacean. Most likely and considering the species of fish that parasitizes, it is a Lernaeocera lusci, a fairly common copepod in species such as european hake, poor cods etc.

These parasites attach to the gill structures of the fish in their juvenile phase, remaining attached there by the cephalic portion, developing an inflammatory lesion around the area where it is embedded and from where it feeds on fish blood and fluids.

Image of copepod attached to lower end of first gill arch.

In this image one can see a fish of the same species without parasitization on the right side, with the gills showing a normal appearance (reddish color and bright appearance).


With the collaboration of the experts of the Fish Pathology Diagnostic Service  (SDPP) of the UAB’s Veterinary Faculty.