Thalasseus, the crested terns, is a genus of eight species of terns in the family Laridae.
The generic name is derived from the Ancient Greek Thalassa meaning "sea".

1/ Greater crested tern (Nhàn mào, Thalasseus bergii), also called crested tern or swift tern
 The species epithet bergii commemorates Carl Heinrich Bergius, a Prussian pharmacist and botanist who collected the first specimens of this tern near Cape Town.

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