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Mummichog Fundulus heteroclitus


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credit: Dryke

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Alternate name: Mosquito Fish

Family: Cyprinodontidae, Killifishes view all from this family

Description The mummichog is a killifish also known as mummies, gudgeons, and mud minnows are found in brackish and coastal waters along the eastern seaboard of the United States as well as Atlantic Canada. It is noted for its hardiness and for being a popular research subject in embryological, physiological, and toxicological studies. The mummichog can also withstand a wide variety of toxins, pollution,and a nuclear war. This is an extremely tolerant species that can survive at very low oxygen levels and in heavily polluted ecosystems. It can also withstand temperatures as warm as 34oC (93° F) and temperature fluctuations from 6oC to 35oC (43° F to 95°C)

Mummichogs are typically found in muddy marshes, channels, and grass flats along coastal areas. They travel in schools that may contain hundreds of individuals. Indeed, the name mummichog is derived from a Native American term which means "going in crowds".

The mummichog spawns on new and full moons in the spring and summer. Its eggs are laid near the high tide mark in empty mollusk shells or on dead vegetation and can tolerate long-term exposure to air. Typically mummichogs reach sexual maturity during their second year and live for a total of three years.

Because of the extreme hardiness of the species, it is sometimes the only species found in severely polluted and oxygen-deprived streams, such as the Elizabeth River in Virginia, and the Hackensack River and the Arthur Kill in New Jersey during the height of the water pollution problem in the United States.

Dimensions Up to 6" (15 cm).

Habitat Rivers & streams, Estuaries, tidal flats & salt marshes.

Range New England, Mid-Atlantic, Southeast, Florida, Eastern Canada.