Accurate. If there is a quality in the cicadas, in particular the cicadas with red eyes of North America, is the accuracy. There are different species, but you can gather in two groups: the first group is composed by species with a life cycle of 13 years, the second (Magicicada septendecim) of 17 years. The latter, after the deposition of the eggs, they pass nearly the whole of the life underground in the larval stage. At the end of the seventeenth year, as if they had a calendar, out from the ground, go on the trees, they become adult insects and mate. And then spawn and die. Confident that the descendants 17 years later will repeat the same cycle. The species is known from the XVIII century, when the colonists on the eastern coast of what would become the United States and Canada became part of this cyclical phenomenon. The species was described and classified by Linnaeus in 1758, and spoke of Thomas Jefferson, the third president of the United States, in one of his writings in 1775.
Billion
This year, usually toward the end of may, the cicadas emerge by the billions from the ground. In the parks of New York city, from Central Park to the Bronx, expect an”invasion” peaceful is because, unlike the devastating locusts, are harmless to both man and crops, apart from the discomfort to the intense chirping. After about 40-45 days, the insects sciameranno to the west, where it will conclude in the midwestern States of their life cycle.
previous
In fact, already in the past few years in the Usa there have been spills of mass of the cicadas, but it was of the species that reproduce every 13 years (Magicicada tredecim), or of egg clutches laid in different years. According to the red list of the Iucn (international Union for conservation of nature) M. septendecim is a species classified as “near threatened”, so not really on the brink of extinction, but is to be protected.