Mergus is the
genus of the
typical mergansers, fish-eating
ducks in the
seaduck subfamily (Merginae). The
hooded merganser, often termed
Mergus cucullatus, is not of this genus but closely related. The other "aberrant" merganser, the
smew (
Mergellus albellus), is
phylogenetically closer to
goldeneyes (
Bucephala).