Originally Posted by
snic
Crayfish are not a type of lobster. They are not even in the same family. Crayfish are also freshwater animals whereas lobsters live in the sea.
Crayfish are 2 to 6 inches long (5 to 15 cm) whereas lobsters are 8 to 20 inches (20 to 50 cm). Lobster thermidor is served in the shell. So one should be able to tell by the size of the "poor creature on your plate" whether it is a crayfish or a lobster.
Going by size, the lobster shell on my plate when I had the Thermidor was more than 6 inches, so I think it's really lobster (in J, on a flight from SIN). Still, the dish wasn't very good. Not sure what the fuss is about. It looks unappetizing and tastes like nothing, at least the version I had.