- Kingdom: Animalia
- Phylum: Mollusca
- Class: Polyplacophora
- Order: Chitonida
- Family: Mopaliidae
- Scientific name: Tonicella marmorea
- Norwegian: praktleddsnegl
This relatively large chiton, reaching a length of 45 mm. The mantle appears smooth, in contrast to smaller T. rubra. The color of the mantle is usually red or green, often with yellow bands. It is in average slightly wider than the mantle of the T. rubra. The shell makes approximately 70% of the body with.
It can be found from the lower tidal zone and down to 250 meters depth. It might appear in large numbers, grazing on organic material on the rock surfaces.
It appears on both sides of the North Atlantic Ocean. In Europe it is known from Norway and Greenland to the Mediterranean.