The Musk Duck - Biziura lobata - is dark grey-brown overall with fine lighter bars visible close-up. Top of the head is darker. Solid head with triangular, dark grey beak. Males have a leathery lobe hanging from the underside of the bill; the stiff and triangular tail is trailed behind the bird or lifted vertically in display. In poor light the bird looks black. Females are smaller, sometimes paler in colour and have very small bill lobes or none at all. Juveniles are smaller with undeveloped bill lobe. Males grow 60 to 70 centimetres, females grow 47 to 53 centimetres.
Spends most of the time on the water; rarely seen to fly or come ashore. If disturbed it swims rapidly on the surface with a flurry or splashing or dives with barely a ripple. Speed when swimming helps to distinguish this species. When it does come ashore it waddles clumsily. In flight has rapid shallow wingbeats; taking off appears difficult, once airborne it can fly well and far but landings are clumsy.
The Blue-billed Duck is similar in appearance to the female Musk Duck. The main difference is in the bill shape.
Lives in permanent swamps and deep permanent lakes and dams with areas of dense reeds as well as open water.
Sedentary and common.