An American cicada whose nymphs emerge from the soil in large numbers periodically. The mature nymphs of the northern species (seventeen-year locust) emerge every seventeen years; those of the southern species emerge every thirteen years. A cicada brood can be so abundant that the shrill sound emitted by the males can damage the human ear.
- ‘The bugs belong to the largest group, or brood, of periodical cicadas - insects that spend most of their lives as nymphs, burrowed underground and sucking sap from tree roots.’
- ‘But the lack of a viable predator control of the periodical cicadas doesn't mean the periodical cicadas have no predators, or no effect on their predators' lives.’
- ‘This year, thirteen-year cicadas will appear in Louisiana, Mississippi, Arkansas, Tennessee, Kentucky, Missouri, and Illinois, and seventeen-year cicadas will show up in Ohio, Pennsylvania, and West Virginia.’
- ‘The fact that periodical cicadas emerge after a prime number of years could be just a coincidence.’
- ‘It is not known how periodical cicadas synchronize their life cycles over 13 or 17 years - or how they manage to count out the years.’
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