Drumming as a Behavioral Line of Evidence for Delineating Species in the Genera Isoperla, Pteronarcys, and Taeniopteryx (Plecoptera)

Abstract

The drumming behavior of nine Isoperla species, Pteronarcys pictetii Hagen, and two Taeniopteryx species are described for the first time. A derived form of drumming in Isoperla ouachita Stark and Stewart, consisting of male calls produced by abdominal rubbing, is reported for the first time in the Perlodidae. Use of drumming behavior as a line of evidence to delineate cryptic and sibling species groups within the genera Taeniopteryx, Pteronarcys, and Isoperla is examined. Male calling of Isoperla species varies from ancestral tapping to rubbing, and there is no overlap in important signal variables between sympatric species. There is no overlap of important drumming variables in the signals of known North American Taeniopteryx and Pteronarcys species, whose signals of both male and female are of a simple, ancestral type, with none of the derived states, such as diphasy or rubbing. Drumming in all known species of the three genera is species-specific, and largely corroborates morphologically based species separations.