Identification
Difficult to tell from closely related S. alutacea, but a few things are fairly constant. The tegmina (front wings) are usually speckled or spotted (sometimes nearly plain, but faint spotting usually still visible), and usually there is no pale stripe on top of these (when folded) and the pronotum. If the stripe is there, it is usually not well-developed, and not very contrasting. In S. alutacea the stripe is often there and often contrasting, and the tegmina are usually plain or only very faintly spotted. The cercus of the males of S. rubiginosa are considerably smaller, which makes males easier to identify than females. The head averages larger in proportion to the thorax, but this is a subtle difference. Shades of reddish brown are the most common coloring, with other hues such as other browns and greys also seen (especially in the far south). Shades of green are very rare.
S. lineata is very similar too, and in the Midwest and northeast this is found too. It differs in the same ways as S. alutacea, except the pale stripe is almost always present, and the front four legs of the males of [i]S. lineata are usually distinctly thickened. Also, it is more often greenish than either of the other two species, though most often it is yellowish brown.
S. damnifica is also similar in coloration, but averages smaller, has the wings usually proportionately shorter, has much shorter (and rather thickish) antennae, has different male genitalia, and has the pronotum higher on top and more "roof-shaped". It is usually plain, not spotted, and the top of the folded wings are usually paler than the sides (not with a narrow pale stripe). The coloration can be almost the same on S. rubiginosa, so is not different enough to always be reliable, but it can give a first clue.
Range
Primarily eastern US (east of the Great Plains), perhaps a bit into s.e. Canada. Most common in the southeast. It has basically the same distribution as S. alutacea, but favors slightly different habitats.
Remarks
This is a member of the "Alutacea" Group, which includes several very closely related populations that are treated by some authors all as subspecies of S. alutacea, by other authors as all distinct species, but which are most often grouped as several subspecies included within a few species. S. rubiginosa is very similar and closely related to S. alutacea, and is often considered a subspecies of that species.
