Periodical cicada Brood XXI is extinct. It was a small brood of Magicicada with a 13-year lifecycle. It was last seen/heard in 1870. Visit Cicadas @ UCONN (formerly Magicicada.org) for more information.
Map from Marlatt, C.L.. 1907. The periodical cicada. Washington, D.C. : U.S. Dept. of Agriculture, Bureau of Entomology:
