Three
genera are included in the Aythyini. The
marbled duck which makes up the
monotypic genus
Marmaronetta, however, seems very distinct and might have diverged prior to the split of dabbling and diving ducks as indicated by morphological and molecular characteristics. but this approach has been questioned.
DNA sequence analyses have found it to be the earliest diverging member of the pochard group. The molecular analysis also suggests that the
white-winged duck should be placed into a
monotypic genus
Asarcornis which is fairly close to
Aythya and might belong into this subfamily.
Family Anatidae •
Subfamily Anatinae •
Tribe Aythyini • Genus
Rhodonessa •
Pink-headed duck (
Rhodonessa caryophyllacea) ; probably
extinct (1945?) • Genus
Marmaronetta •
Marbled duck (
Marmaronetta angustirostris) • Genus
Netta (provisionally including
Rhodonessa) •
Red-crested pochard (
Netta rufina) •
Southern pochard (
Netta erythrophthalma) •
Rosy-billed pochard (
Netta peposaca) • Genus
Aythya •
Canvasback (
Aythya valisineria) •
Common pochard (
Aythya ferina) •
Redhead (
Aythya americana) •
Ring-necked duck (
Aythya collaris) •
Hardhead (
Aythya australis) •
Baer's pochard (
Aythya baeri) •
Ferruginous duck (
Aythya nyroca) •
Madagascar pochard (
Aythya innotata) – feared to be extinct, rediscovered (2006) • Réunion pochard, (
Aythya cf.
innotata) – extinct (c. 1690s) •
New Zealand scaup (
Aythya novaeseelandiae) •
Tufted duck (
Aythya fuligula) •
Greater scaup (
Aythya marila) •
Lesser scaup (
Aythya affinis) ==References==