Distribution and Species of 17-Year Cicadas in Broods V and VIII in Ohio

The distributions of Broods V and VIII of 17-year cicadas, Magicicada spp., were surveyed in Ohio by collecting adults, recording male songs, mapping ovipositional "flagging" records, and using questionnaires. Brood limits in 1965 and 1968 showed signs of receding, primarily away from some large urban centers. Cicada populations of each brood were large and more widespread in southern Ohio. Populations were generally smaller and more isolated in northern counties. M. septendecim (L.) was found in 41 (probably 43) counties in 1965 and in six counties in 1968. M. cassini (Fisher) and M. septendecula Alexander and Moore were recorded from 34 and 23 counties, respectively, in 1965 (Brood V), but not from the northernmost counties. M. septendecula was not found in Ohio in 1968 (Brood VIII); M. cassini was collected from three counties. OHIO J. SCI. 76(6) 254, 1976 Clearing of woods for homes and farm lands has been considered as being instrumental in reducing the distribution of Magicicada spp. (Andrews, 1937; Marlatt, 1907; Parks, 1948). Since the last mapping of the distribution of Brood V in Ohio in 1931 (Parks, 1948), and of Brood VIII in 1917 (Gossard—unpublished records) , there has been an increased utilization of forest land for roads, homes, industries, and farming. In previous surveys by Ohio entomologists, all 17-year cicadas were considered as one species, but today three species are recognized: M. septendecim (L.), M. cassini (Fisher), and M. septendecula Alexander and Moore. After searching insect collections and other available records, Alexander and Moore (1962) indicated that all three species were present in Ohio in Brood V, and only M. septendecim and M. cassini in Brood VIII. However, no complete survey of the distribution of these species within the State has been reported. I studied the current boundaries of Broods V and VIII in Ohio and the distribution of species of 17-year cicadas within these areas. MATERIALS AND METHODS The distribution of 17-year cicadas was de^anuscript received January 7, 1976 (#76-1). Research conducted while employed by Department of Entomology, Ohio Agricultural Research and Development Center, Wooster. termined from questionnaires returned by 74 orchardists in 1965 and 48 in 1968, and by 77 nurserymen in 1965; from reports by extension agents, state research workers, and private citizens; and from a systematic survey in June of every county within or bordering the previously recorded cicada emergence areas. At least one sample of adults was collected in each county where cicadas were present during the survey. County extension agents also submitted samples of adults (24 samples in 1965 and 3 in 1968). A second systematic survey was made of each brood area in midto late summer. At this time, wooded areas showing a fire-scorched appearance (nagging), due to extensive oviposition by the cicadas, were plotted on a road map. Questionable areas were examined more closely for evidence of cicada presence (egg slits, nymphal skins, dead adults). No nagged areas are shown on maps in this report unless they were more than 10 miles long. Boundaries of Broods V in 1965 and VIII in 1968 were drawn with the aid of all positive and negative cicada reports. For comparison with previous Ohio Brood V and VIII distributions, I have reproduced the maps of Gossard (1916), Parks (1948), and Webster (1897; 1900). Since Gossard's map indicated only individual locations of the presence of cicadas, I added a boundary line to show the outermost limit of Brood V. The data for determining the boundary of Brood VIII in 1917 were obtained from Gossard's original unpublished records. Cicada adults were assigned to species according to descriptions given by Alexander and Moore (1932). Confirmation of tentative identification of 25 border-line specimens of M. cassini and M. septendecula in 1965 was made by T. E. Moore, University of Michigan. In 1965, additional species records, based on the song of male cicadas, were supplied by T. E. Moore; R. S. Soper, formerly with Canadian Depart-