Its an air dragon that can become a water dragon by diving into the water to gather food; sometimes diving deep and far into a thousand feet in the water to capture their prey. They are about 9 ft tall, maybe even up to 12 ft depending how long they stay alive. The large eyes are what helps reflect the light off the water and into the water to see prey. Or while in the water, reflect light off to help illuminate the dark water around them to spot their prey after they have dived.
The males tend to have larger frills on the back and the males also tend to have orange pouches of skin on their neck to flare up and intimidate the other males; or impress the females as well. Females don't have the orange on their throat at all.
Its the only real difference and easy, fast way to distinguish the males from the females in this species.
I forgot to mention. This one has a few scars on the side of its neck and such.
The small barb on the tail is used mostly for defense; not actually for hunting. They tend to eat small squid and fish; as well as eel.