Does the Eastern Brown Drake...also have a white male spinner??
No, but it is only the abdomen of the Green Drake spinner that is whitish. The wings of the spinners retain the heavy blackish markings, and the thorax is dark. It is the funereal black-and-white coloration of the male spinners that led to the nickname, Coffin Flies. (The female spinners often have a yellowish tint to the abdomen due to underlying eggs.)
Can you have both species, Green and Brown, come off in the same waters...at the same time?
Yes, when they are present in the same waters, the emergence usually overlaps. However, March Browns (M. vicarium
) are sometimes confused for Brown Drakes and vice versa. Look at the number of tails: March Browns will have two; Brown and Green Drakes will have three.
Any really good way to distinguish these two species from each other besides the slight green color to the wings (green drakes)?
Despite the name, not all populations of Green Drakes have a greenish tint. Green Drakes (E. guttulata
) are typically larger than Brown Drakes (E. simulans
gives the size range for Green Drakes as 18-30mm and Brown Drakes as 13-16mm, but I have seen female Brown Drakes up to 20mm.) Green Drake duns have creamy pale tan to dull yellowish abdomens with a darker brownish (sometimes dark olive) dorsal coloration. The wings are heavily marked with black or dark brown with a slightly yellowish (sometimes greenish) background. Brown Drake duns have tan or yellowish brown abdomens with dark brown patterning on the dorsal surface. The wings typically have dark brown markings on a grayish or yellowish tan background. Green Drakes lose the dark dorsal coloration upon transformation to spinners, but Brown Drakes retain the dark dorsal patterns in the spinner stage. (If you use the site search function to compare the photos of Ephemera guttulata
to the photos of Ephemera simulans
found on this site, the differences should become fairly obvious.)