Chinese mitten crab (Eriocheir sinensis)

Invasive?/Where?

It is mostly found in larger rivers, but migrates towards the sea once in its life, as the offspring need salt water to develop. The young crabs then migrate in turn to freshwater. During these mass migrations upstream, it contributes to temporary local extinctions of native invertebrates, but it feeds primarily on aquatic plants. Its intense burrowing activity alters habitats along the way. Crabs can also be encountered on land as they avoid barriers in their migration. The species originated in Asia and was introduced to Europe in the early 20th century. They are carriers of the deadly fungus "crab plague", to which they themselves are resistant.

Appearance?

Unmistakable by the hair fur on the claws, but in females and juveniles it is not so pronounced. The dorsal carapace can be olive green to brown with dark spots, but there are also bluish and purple color variations. The carapace is finely serrated at the edge.

Distribution in Luxembourg: https://neobiota.lu/eriocheir-sinensis/

Please report the species, if you have seen it, via neobiota.lu