mud·puppy also mud pup·py 
(mŭdpŭp′ē)
(mŭdpŭp′ē)n. pl. mud·pup·pies also mud pup·pies
Any of several large eastern North American aquatic salamanders of the genus Necturus, especially N. maculosus, that have feathery dark red external gills. Also called water dog.