Hartlaub's gull

Hartlaub's gull (Chroicocephalus hartlaubii) is a small gull in the genus Chroicocephalus. It was formerly (as with other related gulls) placed in the genus Larus until genetic research demonstrated that the old broad view of that genus was paraphyletic. In the past it had sometimes been treated as a subspecies of the Australasian silver gull (C. novaehollandiae), but is now treated as a separate species; current genetic evidence suggests its closest relative is not the silver gull but the African and South American grey-headed gull (C. cirrocephalus), and in particular the African subspecies of it C. c. poiocephalus (with the possibility that C. cirrocephalus is paraphyletic with respect to C. hartlaubii: Černý & Natale 2022, Fig. 6).

The species' name commemorates the German physician and zoologist, Gustav Hartlaub. In the past, it was also sometimes known as "king gull".