Ulva torta (Mertens) Trevisan 1842 is a green alga belonging to the section Enteromorpha of the genus Ulva. This Ulva grows in tubular forms rather than blades or sheets. A form of Ulva in Australia was described as U. clathratiodes, and later identified genetically, and later found in Europe, and the East and West Coasts of North America, Hawaii, Japan and Korea. Ulva clathratioides resembles U. clathrata, which grows as branched tubes. It was described from Germany, but has been found on both coasts of North America. Recent genetic identifications have found that U. clathrataioides is conspecific with the European U. torta. Consequently, this species is now treated as cryptogenic in NEMESIS.