The Shenandoah Valley Brood
Brood I is among the smallest broods of 17-year cicadas. The brood is found in the Shenandoah Valley near the Blue Ridge Mountains, with sparse populations along the Blue Ridge Parkway and on Massanutten Mountain. Brood I has disjunct populations on Long Island and near Bristol VA/Bristol TN. This brood includes the species Magicicada cassini, Magicicada septendecim, and Magicicada septendecula.
In the map below, cicada symbols are verified presence records and red crosses are verified absence records in our database as of January 2024. Click on points for details. Gold symbols are from Simon (1988); smaller symbols are records with a lower degree of certainty and black crosses represent records that are considered spurious. Blue symbols are from Marlatt (1923); smaller symbols are records with a lower degree of certainty and question marks represent records that are considered spurious. Symbols are in layered in the order Database, Simon, Marlatt, and symbols in the upper layers may obscure symbols in lower layers. Some absence records in the database are not shown for clarity. Note that the dates shown do not represent dates of adult emergence; rather, they represent dates on which choruses were active. Thus, in any given area, adult emergence may have occurred a week or more earlier than the dates shown on this map. This map may not be reproduced without written permission.