Ulva intestinalis is a filamentous and translucent seaweed with bright green colors, consisting of several irregular tubular unbranched stems with narrowings at the edges and its extremity usually rounded, resembling intestines. Its length varies between 10 and about 30 cm and its diameter ranges between 6 and 18 mm. It has a small base shaped like a disk that allows the seaweed to hold on to the rocks.

Adapted from Pereira, L. 2013 – MACOI,

http://http://macoi.ci.uc.pt/spec_list_detail.php?spec_id=169&searchSpecies=ulva+intestinalis+linnaeus