Mergus

Trivial name	Latin name
Common merganser	Mergus merganser
Red-breasted merganser	Mergus serrator
Hooded Merganser	Mergus cucullatus
Scaly-sided Merganser	Mergus squamatus

comparison of wing and tail configuration¹

¹ According to Hartmann (2000a, 2000b and 2016)