Periodical cicadas
Magicicada is the genus of the 13-year and 17-year periodical cicadas of eastern North America. Although they are sometimes called "locusts", this is a misnomer, as cicadas belong to the taxonomic order Hemiptera (true bugs), suborder Auchenorrhyncha, while locusts are grasshoppers belonging to the order Orthoptera.[2] Magicicada belongs to the cicada tribe Lamotialnini, a group of genera with representatives in Australia, Africa, and Asia, as well as the Americas.[3]
Magicicada species spend almost the full length of their long lives underground feeding on xylem fluids from the roots of deciduous forest trees in the eastern United States.[4] In the spring of their 13th or 17th year, mature cicada nymphs emerge in the springtime at any given locality, synchronously and in tremendous numbers. After the prolonged developmental phase, the adults are active for only about 4 to 6 weeks.[5] The males aggregate into chorus centers and attract mates. Mated females lay eggs in the stems of woody plants. Within two months of the original emergence, the lifecycle is complete and the adult cicadas disappear for another 13 or 17 years.
The winged imago (adult) periodical cicada has red eyes and a black dorsal thorax. The wings are translucent and have orange veins. The underside of the abdomen may be black, orange, or striped with orange and black, depending on the species.[6]
Adults are typically 2.4 to 3.3 cm (0.9 to 1.3 in), depending on species, slightly smaller than most of the annual cicada species found in the same regions of the United States. Mature females are slightly larger than males.[7]
Magicicada males typically form large aggregations that sing in chorus to attract receptive females. Different species have different characteristic calling songs. The call of decim periodical cicadas is said to resemble someone calling "weeeee-whoa" or "Pharaoh".[8] The cassini and decula periodic cicadas (including M. tredecula) have songs that intersperse buzzing and ticking sounds.[7]
Cicadas do not sting and do not normally bite. Like other Auchenorrhyncha bugs, they have mouthparts used in piercing plants and sucking their sap. A cicada's proboscis can pierce human skin when it is handled, which is painful, but in no other way harmful. These cicadas are not venomous, and no evidence shows they transmit diseases. They pose little threat to mature vegetation, although planting new trees or shrubs is best postponed until after an expected emergence of the periodical cicadas. Mature plants rarely suffer lasting damage, although twig die-off or flagging can result from egg-laying.[9] Young trees or shrubs can be covered with cheesecloth or a similar material to prevent damage during the oviposition period, which begins about a week after the first adults emerge and lasts until the females have died.
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