Fishhook waterflea

Cercopagis pengoi


Photo credit: ©USGS
Cercopagis pengoi
  • It is found in estuarine habitats, lakes, marine habitats, water courses, and wetlands.

  • This species can only be identified using a microscope. When magnified, a unique loop at the end of its tail, as well as a pointed brood pouch which may contain eggs can be seen.
  • Please see the Global Invasive Species Database for a more detailed description of this species.

Origin and Distribution:
  • Originates in the Caspian, Black and Azov seas and small coastal lakes in this area. Considered invasive in Eastern Europe, Baltic Sea, Laurentian Great Lakes and Finger Lakes.

  • Occurring in estuaries, lakes, water courses, and wetlands. It is a voracious predator and may compete with other invertebrates and vertebrates. Through this competition, C. pengoi has the potential to affect the abundance and condition of fish and fish larvae; this species also impacts fisheries by clogging nets and fishing gears.

How might it get here?
  • The only described vector for this species is ships ballast water.

Is it found in Ireland or Northern Ireland?
  • It is not found in Ireland or Northern Ireland.

Prevent Spread:
  • Bait or bait water should not be released into water body or transport from one water body to another.
  • Good containment measures should be followed to control both the spread of adults and resting eggs, which are capable of surviving desiccation and freezing for periods of several years. 
  • Report all sightings.

You can help by reporting any sightings:
Invasive Species Ireland

Invasive Species Ireland