Hector's dolphin, one of the rarest and smallest of marine dolphins (6), has a short, stocky torpedo-shaped body, which becomes narrow towards the tail. The beak is short and the rounded snout lacks a melon. The sides and back are light grey, there is a darker stripe along the middle, and the underside is whitish (4). The large tail flukes, flippers and characteristically rounded dorsal fin are all black (5). A black marking extends from the snout back around the eye reaching to the flipper (5). Males and females are generally similar in appearance, but females tend to be slightly longer than males (5). Calves have the same markings as adults but pale lines can be seen on darker areas, and the underside has a yellowish tint (5). The common name of this dolphin refers to the New Zealand zoologist Sir James Hector (5), who first collected the species in 1869 (4).