• Flat and transparent larva of eel.

• They have laterally compressed body that contains transparent jelly like substances inside the body.

• Their organs are small they have only a simple tube.

• They have dorsal and anal fin but lack anal fin.

• They also lack RBC until they begin to metamorphosis into juvenile glass eel stage.

• They show catadromous migration that is fresh to marine water. They differ from other fish larvae because they grow to a much larger size.