any of various goby fishes that are able to leave the water regularly when living in mud flats or climbing mangrove roots in search of food
See mudskipper in American Heritage Dictionary 4
(mŭdˈskĭpˌər)
noun
Any of several fishes of the family Gobiidae, especially of the genus Periophthalmus, that are found along the western coast of tropical Africa and in the Indo-Pacific region and are able to survive out of water and maneuver on land.