European green woodpecker though the latter is smaller and more slender with narrower wings and longer tail. The closely related, very similar Levaillant's woodpecker occurs only in north-west Africa. The European green woodpecker is a member of the order Piciformes, the woodpecker family Picidae and the genus Picus. It was first described by Linnaeus in 1758. The scientific name is derived from the Greek "pikos", meaning 'woodpecker', and Latin "viridis", 'green'. There are four subspecies, with subtle and mostly clinal differences between them. In a recent study based on mitochondrial DNA analysis of subspecies by Perktaş, Barrowclough and Groth, it has been proposed
Imperial woodpecker Imperial woodpecker The imperial woodpecker ("Campephilus imperialis") is a species of bird, a member of the woodpecker family Picidae. The genus "Campephilus" is essentially a tropical one, embracing 13 species, including the imperial woodpecker. If it is not extinct, it is the world's largest woodpecker species, at long. Researchers have discovered that the imperial woodpecker has slow climbing strides and a fast wing-flap rate compared with other woodpeckers. Owing to its close taxonomic relationship, and a similarity in appearance, to the ivory-billed woodpecker, it is sometimes called the "Mexican ivorybill", but this name is also used for the pale-billed woodpecker.