Achtheres is a parasitic copepod that infects the gills of freshwater fish and is most easily visible once they mature and move into the fish’s mouth. For those that haven’t seen them, mature adults resemble a small white dot (less than 1/8”) with what look like legs. Those ‘legs’ are actually the egg sacs of the female parasite which are in the last stage of their life cycle.
Despite being unattractive, there is little cause for alarm. These parasites have not directly caused a fish kill in the waters where they have been found, and are harmless to humans since they are not found