The Mummichog (Fundulus heteroclitus) is a small killifish found in the eastern United States. It is capable of tolerating very variable salinity and temperatures, and is found in estuaries and saltmarshes as well as less salty waters.
Its eggs stick to submerged plants and green algae. The eggs are used in teaching embryology, because it is possible to see the eyes and the beating heart and follow the different stages of ontogenesis. These fish are used to stock otherwise fishless ponds that breed mosquitos, and within three days the ponds are normally mosquito free.
