As mystical as the legendary creature that shares its name, the sea dragon is a cryptic marine fish that uses color and weed-like appendages to camouflage itself. There are two types of sea dragons, which are related to the seahorse: leafy and weedy. These creatures are found around southern and western Australia. Leafies are generally brown to yellow in body color with spectacular olive-tinted appendages. Weedies have less flamboyant projections and are usually reddish in color with yellow spots.

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The leafy sea dragon propels itself by means of a pectoral fin on the ridge of its neck and a dorsal fin on its back closer to the tail end. These small fins are almost completely transparent and difficult to see as they undulate minutely to move the creature sedately through the water, completing the illusion of floating seaweed.

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The Leafy Sea Dragon has the ability to change color and can do so more effectively based on the sea dragon's diet, age, location, and stress levels. Sea dragons, sea horses and pipe fish are the only species where the male carries the eggs.

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Photo by Lester A. Arcega

This is obviously not a real sea dragon but it's still a nice image, from Lush.i.ous.

Text adapted from Wikipedia: 1, 2 & National Geographic.