- Kingdom: Animalia
- Phylum: Annelida
- Class: Polychaeta
- Subclass: Sedentaria
- Order: Terebellida
- Family: Pectinariidae
- Scientific name: Lagis koreni
- Norwegian: krumkakemark
The trumpet worm inhabits a tube made from a single layer of sand grains. The tube is open in both ends. The short and thick body is divided into three regions. The front region has bundles of spines used for digging. Behind these a mouth is surrounded by tentacles. L. koreni, formerly known as Pectinaria koreni, is the most common trumpet worm in Norway. It can grow to a length of 6 cm and build 8 cm long, slightly curved, tubes.
Abundant in fine substrate of sand and silt, where they live partially buried.
Widespread in the North-East Atlantic Ocean.