Examination of the male reproductive parts are needed for identification. Even then, it can be a little difficult to distinguish from S. pistillata. The lobes seem a bit more pointed in S. pistillata, and more squared off in S. curvicauda. S. curvicauda also has narrower wings than S. pistillata.
SINA genus page with diagrams comparing male terminalia: https://orthsoc.org/sina/g060a.htm
BugGuide genus page showing pictures of male terminalia: https://bugguide.net/node/view/7130
Blatchley, W. S. 1920. Orthoptera of northeastern America: with especial reference to the faunas of Indiana and Florida. Nature Publishing Company.
Statewide. Occurs throughout the eastern U.S.
Greenery from marshy meadows to trees and undergrowth. Blatchley (1920) stated that he found it most often in marshy meadows in Indiana, but that it had been reported more often from trees and undergrowth farther north.