New Descriptions of North American Euholognathan Stonefly Drumming (Plecoptera) and First Nemouridae Ancestral Call Discovered in Soyedina carolinensis (Plecoptera: Nemouridae)

Abstract

Drumming is described for the first time in the stonefly species Zealeuctra warreni Ricker ,& Ross (Leuctridae), Soyedina carolinensis (Claassen) (Nemouridae), Taeniopteryx ugola Ricker & Ross (Taeniopterygidae), and in a Nebraska population of Taeniopteryx burksi Ricker & ROSS. Z. warreni males call with simple, eight-beat monophasic signals that have average 68.5-ms beat intervals, and these conform to the ancestral pattern previously described for three other Zealeuctra species. S. carolinensis males call with 16-beat signals having average 24.8-ms intervals; this is the first discovery of an ancestral call pattern in the family Nemouridae. T. ugola has a three-way duetting pattern, consistent with drumming of four North Americar congeners. Their duets are unique, with mode 10-beat calls, nine-beat female answers, and six-beat male replies. Beat intervals of T. ugola calls are uniform and therefore more ancestral than those of its congeners. Calls of a Nebraska population of T. burksi had almost idsntical beat intervals compared with those previously reported from an Oklahoma populatior, suggesting no call dialect between the populations found in streams of different biomes and separated by ≈9° latitude and 8° longitude. Implications of these data to the diversity of dn. mming in the Euholognatha and evolution of the behavior in Plecoptera are discussed.