Red-headed Woodpecker Taxonomy (1 Viewer)

I'm not sure if anyone can answer this, but it never hurts to ask....

According to the ITIS and this Wikipedia article, there are 2 (Melanerpes erythrocephalus erythrocephalus and M. e. caurinus) or 3 (M. e. erythrocephalus, M. e. caurinus, and M. e. brodkorbi) subspecies of the Red-headed Woodpecker. But the Internet Bird Collection states that the species is monotypic. What is the history behind Red-headed Woodpecker subspecies taxonomy, and what do the major taxonomists accept today, or had accepted at one time? What are the differences between each subspecies, whether accepted or not?

This probably makes absolutely no sense, but thanks for bothering to read! :-O

The Birds of North America online:

• "No subspecies recognized following Short (1982). Larger western populations (s. British Columbia to w. Ontario, Uinta basin of Utah, to n. Texas Panhandle and se. Texas to Taylor and Wilbarger Cos.) that more frequently have red on belly were named as a separate subspecies, M. e. caurinus, by Brodkorb (1935), who renamed M. e. erythrophthalmus of Oberholser (1919) and designated type locality of this taxon as Lodgepole Creek, 2 miles northwest of Chappell, Deuel Co., NE."

Winkler et al 1995. Woodpeckers:

• "Northwestern populations of the western Great Plains south and west to C Colorado have been separated as 'caurinus'; they are slightly longer-winged (surely as a result of their more migratory habits) and perhaps with slightly deeper yellow wash below (though this varies greatly among all populations). Their racial separation seems unwarranted."

BNA, Winkler et al, Dickinson (H&M), Clements, Alderfer (National Geographic) & HBW all now consider Red-headed Woodpecker to be monotypic.

Richard

Here's what BNA online (http://bna.birds.cornell.edu/bna/species/518/articles/systematics) has to say on the subject:
"No subspecies recognized following Short (1982). Larger western populations (s. British Columbia to w. Ontario, Uinta basin of Utah, to n. Texas Panhandle and se. Texas to Taylor and Wilbarger Cos.; see Oberholser 1974) that more frequently have red on belly were named as a separate subspecies, M. e. caurinus, by Brodkorb (1935), who renamed M. e. erythrophthalmus of Oberholser (1919) and designated type locality of this taxon as Lodgepole Creek, 2 miles northwest of Chappell, Deuel Co., NE. The race caurinus was recognized by Am. Ornithol. Union (1957)."

Edit: opps, sorry. Somebody else got there first, I see

Thank ya much!