[luhng-fish] 
) -fish, (especially referring to two or more kinds or species) -fish⋅es. | any of various slender, air-breathing fishes of the order (or subclass) Dipnoi, of rivers and lakes in Africa, South America, and Australia, having a lunglike air bladder as well as gills and growing to a length of 3 to 6 ft. (0.9 to 1.8 m). |
| lung·fish (lŭng'fĭsh') n. pl. lungfish or lung·fish·es Any of several elongated freshwater fishes of the Amazon, western and central Africa, and Australia that have lunglike organs as well as gills and are able to breathe air, allowing certain species to survive periods of drought inside a mucus-lined cocoon in the mud. |
lungfish
any of six species (three species according to some authorities) of air-breathing fishes placed with a number of extinct forms in the subclass Dipnoi (order Dipnoi of some authorities). The Dipnoi first appeared in the Lower Devonian Period (about 370,000,000-395,000,000 years ago). The extant species occur in rivers and lakes in Africa, South America, and Australia. They are especially interesting because of their characteristic body forms, their generally large size, their erratic distribution over the tropical regions of the earth, and their peculiar mode of life.
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