Chatham Island merganser

The Chatham Island merganser (Mergus milleneri) is an extinct species of merganser duck from New Zealand. The binomial name refers to Dr. Philip Millener, to recognise his work in collecting material on the species.

Description
The Chatham merganser is known only from subfossils, so not much is known about the bird. It was the smallest of all Mergus species. Fossil records indicate it was widespread on Chatham Island but not on the smaller nearby islands.