The Wels Catfish (Silurus glanis), or sometimes called the sheatfish, is a large catfish native to central, southern and eastern Europe, although it has now been introduced to parts of Western Europe. It is a freshwater fish. It has no scales and can be recognised by its large, broad head. They can live for around 50 years and have excellent hearing. It is very territorial when guarding its eggs, and has been known to attack humans who swim too close. It is classed as Least Concern on the IUCN Red List.