A striking case of deceptive woodpecker colouration: the threatened Helmeted Woodpecker Dryocopus galeatus belongs in the genus Celeus

Abstract

The Helmeted Woodpecker Dryocopus galeatus is a threatened species of the Atlantic Forest in southeastern South America. It has traditionally been placed in the genus Dryocopus, but it shows similarities in plumage and structure with woodpeckers in the genus Celeus. We sequenced mitochondrial and nuclear DNA that was sampled from live captured Helmeted Woodpeckers. We found that the Helmeted Woodpecker has a phylogenetic position embedded within the genus Celeus, and recommend its taxonomic treatment as Celeus galeatus. The Helmeted Woodpecker belongs to a clade within Celeus that includes Kaempfer’s Woodpecker C. obrieni, Rufous-headed Woodpecker C. spectabilis, and Cream-coloured Woodpecker C. flavus. It has the southernmost distribution range of the woodpeckers in this clade. The Helmeted Woodpecker is sympatric throughout its range with Lineated Woodpecker Dryocopus lineatus and Robust Woodpecker Campephilus robustus and these species from three different genera show a remarkable convergence in plumage colours and patterns. With the inclusion of Helmeted Woodpecker in Celeus, this genus has four out of 15 species on the International Union for Conservation of Nature (IUCN) red list, a higher proportion of red listed species than in the woodpecker family overall.