Mareca is a genus or subgenus of ducks in the family Anatidae that includes the wigeons.
The species now placed in this genus were formerly placed in the genus Anas. A molecular phylogentic study comparing mitochondrial DNA sequences published in 2009 found that the genus Anas, as then defined, was not monophyletic.[1] Based on the published phylogeny, the genus Anas was split into four monophyletic genera with five extant species moved into the resurrected genus Mareca.[2]
^ abGonzalez, J.; Düttmann, H.; Wink, M. (2009). "Phylogenetic relationships based on two mitochondrial genes and hybridization patterns in Anatidae". Journal of Zoology. 279 (3): 310–318. doi:10.1111/j.1469-7998.2009.00622.x.