South American Lungfish

The South American lungfish is an eel-bodied, thread-finned fish of the Amazon, Paraguay, and lower Parana river basins, reaching up to about 1.25 meters long. Juveniles are strikingly spotted gold on black, a pattern that fades to plain brown or gray as they mature. Its gills are reduced to the point of being effectively nonfunctional in adults, making it an obligate air-breather dependent on a pair of lungs. When its swamp habitat dries up, it burrows into the mud, seals a chamber with mucus, and slows its metabolism to wait out the dry season in dormancy.