Picoides
Picoides is a genus of woodpeckers that are native to Eurasia and North America.
Taxonomy
The genus Picoides was introduced by the French naturalist Bernard Germain de Lacépède in 1799. The type species was subsequently designated as the Eurasian three-toed woodpecker by the English zoologist George Robert Gray in 1840. The genus name combines the Latin Picus for a woodpecker and the Greek -oidēs meaning "resembling". The genus Picoides formerly contained around 12 species. In 2015 a molecular phylogenetic analysis of nuclear and mitochondrial DNA sequences from pied woodpeckers found that three existing genera were polyphyletic. After the resurrection of five monophyletic genera and the subsequent rearrangement in which most of the former members of Picoides were moved to Leuconotopicus and Dryobates, only three of the original species remained.Description
The males of all three species have yellow on the crown, though this feature is also present in some other pied woodpeckers, namely brown-fronted and yellow-crowned. The remaining color pattern of the plumage, structural features, and life habits are very similar to related woodpeckers of the Dryobates and Leuconotopicus genera. The foot of all three species show an extreme adaptation to arboreal living by lacking the first digit, or hallux. It has been pointed out however that various species of pied woodpecker are similar in having a short first digit. Two species of woodpecker in genus Sasia also lack the first digit.Habits
As opposed to genus Dryobates, the three species of Picoides obtain most of their insect prey by pecking live or dead wood. The hairy woodpecker for instance, obtains only 45% of its food by pecking wood, 30% from the surface of trunks and 25% at other places.Species
The genus contains the following three species:| Image | Name | Common name | Distribution |
| Picoides tridactylus | Eurasian three-toed woodpecker | across western Canada, Alaska and the midwestern United States, and across northern Eurasia from Norway to Korea. | |
| Picoides dorsalis | American three-toed woodpecker | western Canada, Alaska and the western United States | |
| Picoides arcticus | Black-backed woodpecker | Canada, Alaska, the north-western United States |