Mixed 13-year Magicicada -decim chorus

Sonogram (graph of frequency, or pitch, vs. time) showing a mixed M. neotredecim and M. tredecim chorus of male calls with one call of each species standing out against the background chorus. Individual calls end with a downslur. Faint slurs of background chorus males overlap and are not visible. This chorus was recorded in northern Arkansas in June, 1998.