Quagga Mussel (Dreissena rostriformis)
Closely related and very similar to the zebra mussel, but possibly even more invasive. Found in freshwater rivers, canals and lakes, it can survive in some places that zebra mussel can’t and can even displace them. Like the zebra mussel and killer shrimp this species comes from the ponto-caspian region in south-east Europe. In October 2014, the first GB record of Quagga Mussel was confirmed in
West London. Any suspected sighting should be reported as soon as possible using the guidance below.
Similar to zebra mussel and quite difficult to distinguish, if you suspect quagga mussel make sure to make a note of where you saw it and inform the relevant organisation (the Environment Agency in England and Wales, the Scottish Environment Protection Agency in Scotland).
Identification tips:
- found in freshwater rivers, canals and lakes
- small – similar in size to zebra mussel
- lacks the strong ridge that gives zebra mussel its ‘D’ shape, quagga mussel is more rounded
- when you place quagga mussel on its front it will roll to one side, unlike zebra mussel
- a wavy line is created by the meeting of the two halves of the shell in quagga mussel, in zebra mussel the line is more straight
- living zebra mussels are quite hard to detach from a surface they are attached to, quagga mussels pull off more easily
If you spot a Quagga Mussel, you should report it here: