Common Whitetails don't seem to be all that common locally, or maybe I'm not looking in the right habitat. This is a male, about 50 mm long. Females lack the bloom on the abdomen and their wing spots resemble those of a Twelve-spotted Skimmer.
A Common Whitetail female: note the series of black, white and yellow diagonal dashes on the abdomen. Compare this to the Twelve-spotted Skimmer's continuous pale grey stripe.
Common Whitetails are apt to be more frequently encountered as one travels east along the Eastern Ontario Trail. This immature male's wing pattern is diagnostic, but its abdomen (not visible from this angle) bears the same pattern as the female's. It will develop the signature "white tail" as it attains full maturity.
