This sea squirt is probably spread by ballast water and is now far found around the world.
The first observation of this ascidian from the Oosterschelde, was done in 1977. It is now massively found in the waters of Zeeland.
With a thin gelatinous membrane to cover various hard substrates. The colonies have combined exhalent openings which are generally quite large.

The colonies can be tens of square centimeters in size and are usually a few millimeters thick.

Variable from almost transparent to dark grey.

Shallow waters, attached to hard substrate.

This species has a global distribution.