FIGURE 6 in A new Neotibicen cicada subspecies (Hemiptera: Cicadidae) from the southeastern USA forms hybrid zones with a widespread relative despite a divergent male calling song

FIGURE 6. Field recordings of putative hybrids between subspecies of Neotibicen similaris; A–D; spectrograms showing a range of phenotypes exhibiting different combinations of the parental song characters from four different locations (see track ID at bottom right); E, zoomed waveform and spectrogram of the song in D, showing the long high-pitched echeme of N. similaris apalachicola n. subsp. followed by a set of short echemes matching those of N. similaris similaris. Sound energy below 1.8 kHz has been removed.