Forty-nine Colorado birds of 6 galliform species were positive for Plasmodium (Giovannolaia) pedioecetii which we feel to be the same parasite described by Wetmore (1939) from a shaptailed grouse from North Dakota. Except for its presence in Darwin's tinamou (Nothura darwinii) from Colorado, it has been reported only from gallinaceous birds. Most stages were predominantly subpolar to polar. There were a daily 8 am to noon peak of merozoite production, but no synchronicity. Merozoite number ranged from 8 to 22, with a mean of 10.9. Gametocytes were long and slender, some curving around one end of the host nucleus.