Kung Nueng (Steamed Shrimp) กุ้งนึ่ง
Steamed Shrimp purchased at Jomtien Beach. Are these shrimp or prawns? In the USA, people commonly call large shrimp "prawns", but that's not correct because some prawns can be smaller than shrimp. Some people think shrimp are saltwater and prawns are freshwater. That's not correct either.
This is the difference:
The structure of the gills is different between shrimp and prawns. If you turn a shrimp over and look at its "belly";, the side plate of the second segment of the abdomen overlaps the segments in the front and behind. If you do the same to a prawn, all of the abdominal side plates overlap like tiles from the front.
Shrimp "brood" their eggs like a chicken (the eggs are held in their swimming legs -- See en.wikipedia.org/wiki/Pleopod). Prawns don't brood -- They just shed their eggs into the current.
Look at the eggs held by the swimming legs of these shrimp!