The mandarin duck (Aix galericulata) is a perching duck species found in East Asia. It is medium-sized, at 41-49 cm (16-19 in) long with a 65-75 cm (26-30 in) wingspan. It is closely related to the North American wood duck, the only other member of the genus Aix.
The wood duck or Carolina duck (Aix sponsa) is a species of perching duck found in North America. It is one of the most colorful North American waterfowl. The wood duck is a medium-sized perching duck. A typical adult is from 47 to 54 cm (19 to 21 in) in length with a wingspan of between 66 to 73 cm (26 to 29 in). This is about three-quarters of the length of an adult mallard.