The carpet sea squirt was found by scientists at Largs Yacht Haven
A small colony of an invasive creature known as carpet sea squirt has been discovered at Largs on the Firth of Clyde.
It is the first time the spongy species, also called didemnum vexillim, has been sighted in Scotland.
It reproduces quickly and scientists have raised fears it may threaten other marine life.
It is thought it may have been brought into Scottish waters from Wales or Ireland on the hulls of leisure boats.
Surveys will now be carried out to investigate how widespread it has become and how it will be dealt with.
The work will be funded by Scottish Natural Heritage (SNH) and Marine Scotland.
Marine scientists have been on the lookout for the non-native invasive species in Scottish waters since it was found in Holyhead Harbour in North Wales in 2008.
The Scottish colony was discovered in Largs Yacht Haven.
Carpet sea squirt is a distinctive mustard, pale orangey-yellow or beige colour and often appears as pale flat patches.
Larger growths may look like wax dripping from artificial structures just below water level.
It is most likely to spread by attaching itself to the hulls of boats and vessel owners have been asked to make extra efforts to keep hulls clean to help prevent its spread.
Dr David Donnan, from SNH said: "The carpet sea squirt can reproduce and spread rapidly and tends to smother other marine life that grows on the seabed.
"It has spread around the world although it is thought to have originally come from Japan.
"Experience from Canada, New Zealand, continental Europe and Ireland has highlighted it as a potential nuisance species that causes economic and environmental problems."
Chris Beveridge from the Scottish Association for Marine Science (SAMS) spotted the colony at Largs during a routine survey.
She said: "The sea squirt may have been brought into Largs Yacht Haven on the hulls of leisure craft which have travelled from Wales or Ireland, where it is already established.
"It could be a real menace for all users of the marine environment if it spreads up the coast, with considerable economic impact."