The sunfish can grow to 4m in length and weigh more than a tonne
The sunfish was discovered by a member of the public at East Bay beach who contacted the nearby aquarium.
Aquarists retrieved the stranded fish, which was around a metre long, however, it later died.
Deep Sea World's Chris Smith said: "This is the first sunfish stranding I have seen in the local area."
He added: "Sunfish spend their lives in the deep ocean so for it to end up stranded on a beach indicated it was in a very bad way.
"We brought it back to the aquarium and put it into one of our quarantine tanks where we did everything we could for it but sadly it died within an hour."
Tropical waters
Sunfish are the heaviest-known bony fish in the world with an average adult weight of about a tonne.
The maximum recorded specimen weighed 2.3 tonnes and was more than 4m (13ft) long - the height of a double decker bus.
The fish are found in temperate and tropical waters around the world but are sometimes spotted from boats off the Scottish coast.
Chris Smith added: "There are a few reports each year of sunfish sightings, mainly from fishing vessels as the fish have a funny habit of swimming on their side just under the surface of the water.
"They are usually summer visitors as they mainly eat jellyfish which are more abundant when the water is warmer.
"As this was so unusual we have been in contact with the National Museums of Scotland in Edinburgh who have said they would like to keep it as part of their research collection."
Reader Comments
to our Newsletter