Thin sections of limestone from the Upper Devonian Waterways Formation from the subsurface of Alberta, western Canada, reveal the presence of calpionellids, the fossilized loricas (tests) of ciliate protozoa. They are described as Vautrinella devonica sp. nov. This is apparently the earliest record of calpionellids to date, only one other occurrence of Paleozoic forms of the group being known to the authors. These Devonian calpionellids are interpreted as being a marine planktonic group which inhabited the Waterways sea. In many instances thin sections show inclusions of pyrite aggregates and grains within the calpionellid loricae which are asymmetrically distributed.