The western rockhopper penguin (Eudyptes chrysocome) is a species of rockhopper penguin. It occurs in subantarctic waters around the southern coast of South America and nearby islands. The western rockhopper penguin was formerly considered to be conspecific with the eastern rockhopper penguin (Eudyptes filholi) of the western Pacific and Indian Oceans, with the combined species then known as southern rockhopper penguin. These two taxa together had previously also been considered conspecific with the northern rockhopper penguin (E. moseleyi).
In 1743 the English naturalist George Edwards included an illustration and a description of the western rockhopper penguin in the first volume of his A Natural History of Uncommon Birds. Edwards based his hand-coloured etching on a preserved specimen owned by Peter Collinson. When in 1758 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the tenth edition, he placed the western rockhopper penguin with the red-billed tropicbird in the genus Phaethon. Linnaeus included a brief description, coined the binomial name Phaethon demersus and cited Edwards' work. The use of Linnaeus' binomial name was not adopted by later...