- Kingdom: Animalia
- Phylum: Annelida
- Class: Polychaeta
- Subclass: Errantia
- Order: Phyllodocida
- Family: Polynoidae
- Scientific name: Alentia gelatinosa
- Norwegian: -
This bristle worm may reach a length of 9 cm. Its most typical feature is the 18 pairs of soft and semitransparent shells, giving it a gelatinous appearance. The dorsal side is white, yellow, or even orange, as the specimen below. Sometimes it has transverse brown and white bands. The body is flattened. It may move with a considerable speed (1-2 cm/sec) when disturbed.
It thrives on sandy substrate, often under rocks in the subtidal zone.
The is registered in the East Atlantic Ocean, from West Africa to the North Sea.