Ivory-billed Woodpecker Classification

There are either 11 or 12 Campephilus species depending on how the Ivory-billed Woodpecker is classified.  Scientists who analyzed mitochondrial DNA of museum specimens reported in 2006 that their data suggested that the Cuban Ivory-billed Woodpecker and the US Ivory-billed Woodpecker should be considered as separate species in Mid-Pleistocene divergence of Cuban and North American ivory-billed woodpeckers by Robert C. Fleischer, et al., Biol Lett. 2006 September 22; 2(3): 466–469.  Published online 2006 May 16. doi: 10.1098/rsbl.2006.0490.  

Historically, they had been considered to be the same species. 

The American Ornithologists' Union Committee on Classification and Nomenclature is the ultimate authority on the issue, according to the issue of BirdWatch at this link.