Bug FAQCassin's 17-year Cicada
Magicicada cassinii · Order: Hemiptera · Family: Cicadidae
Also called: dwarf periodical cicada, Cassini Periodical Cicada
Source: Wikipedia
Cassin's 17-year cicada is a large black insect with orange legs and translucent wings marked with orange veins. Adults emerge every 17 years, feed on tree sap, and the females can harm young trees when they lay eggs.
Source: Wikipedia
How to recognize it
The head is black with large red eyes, the pronotum is black with a thin orange edge, the abdomen is black, legs are orange, and the wings are clear with orange veins and darker tips.
Source: Wikipedia
Size
Adults are 24 to 27 mm long from head to wing tip.
Source: Wikipedia
Is it a pest in the house?
In outbreak years, females cut slits in twigs to lay eggs, which can cause young shoots to droop and lose leaves.
Source: Wikipedia
Where it lives
They live across the northern United States and southern Canada.
Source: Wikipedia
What it eats
After emerging, they sip sap from trees and shrubs.
Source: Wikipedia
Life cycle
They spend 17 years underground, molting five times as they move to deeper roots. They emerge in 17-year cycles and look like the 13-year Magicicada tredecassini.
Source: Wikipedia
When you see it
The most recent brood emerged in many eastern states in May-June 2021.
Source: Wikipedia
Where it comes from
Their range covers the northern belt of the U.S. and the southern part of Canada.
Source: Wikipedia
Where it is found in the US
Recorded in 23 of 51 states and DC. Most records: Illinois, Maryland, Ohio, Kentucky, Virginia, Indiana, Kansas, Tennessee.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
Do Cassin's 17-year cicadas damage trees?
Yes, the females cut slits in twigs to deposit eggs, often causing shoots to droop and defoliate.
Source: Wikipedia
Same family (Cicadidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Magicicada_cassini
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.