- Kingdom: Animalia
- Phylum: Chordata
- Subphylum: Tunicata
- Class: Ascidiacea
- Order: Aplousobranchia
- Family: Didemnidae
- Scientific name: Diplosoma listerianum
- Norwegian: -
This colonial sea squirt forms thin (1-2 mm) gelatinous sheets. The small zooids (animals) are densely scattered throughout the sheet. The colony is semitransparent. There is a pattern of yellow pigmented spots in the surface layer.
It sits on smooth substrate, stones or even kelp, on depths ranging from the subtidal zone to 80 meters.
This is a cosmopolitan, known from all oceans worldwide.