Egretta is a genus of medium-sized herons, mostly breeding in warmer climates.
The genus name comes from the Provençal French for the little egret, aigrette, a diminutive of aigron, "heron".

1/ Pacific reef heron (Cò đen, Egretta sacra), also known as the eastern reef heron or eastern reef egret
2/ Little egret (Cò trắng, Egretta garzetta) 
The species epithet garzetta is from the Italian name for this bird, garzetta or sgarzetta.
3/ Chinese egret or Swinhoe's egret (Cò trắng Trung Quốc, Egretta eulophotes)

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