| Tadornini | |
|---|---|
 | |
| Common shelduck (Tadorna tadorna) | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Anseriformes |
| Family: | Anatidae |
| Subfamily: | Anatinae |
| Tribe: | Tadornini Reichenbach, 1849 |
| Genera | |
See text | |
TheTadornini is a biologicaltribe that includes theshelducks andsheldgeese, which is placed in subfamilyAnatinae of familyAnatidae, which includes theducks and most duck-like waterfowl such as thegeese andswans. It has been treated as subfamily in the past.
This group is largely tropical or Southern Hemisphere in distribution, with only two species, thecommon shelduck and theruddy shelduck breeding in northern temperate regions, though thecrested shelduck (presumed extinct) was also a northern species.
Most of these species have a distinctive plumage, but there is no pattern as to whether the sexes are alike, even within a singlegenus.
Following the review of Livezey (1986),[1] several species formerly classified as aberrantdabbling ducks or as "perching ducks" were placed in the Tadornini.mtDNAsequence analyses[2][3] cast doubt on the allocation of several genera; many supposed dabbling ducks and one peculiar goose may more correctly belong here, while some genera believed to be close to shelducks appear to have different relationships altogether.
The available data indicates that the Tadornini are indeed, as their appearance suggests, somewhat intermediate between geese and dabbling ducks, but the molecular data suggests they are not the only lineage to evolve towards a more duck-likemorphology, with thediving ducks andseaducks being more distant.
