Brood XIX
Encyclopedia
Brood XIX is the largest (most widely distributed) brood of 13-year periodical cicadas
, last seen in 1998 and reappearing in May and June of 2011 across a wide stretch of the southeastern United States. Periodical cicadas (Magicicada spp.) are often referred to as "17-year locusts" because most of the known distinct broods have a 17-year life cycle. Brood XIX is one of only three surviving broods with a 13-year cycle. It is also notable because it includes four different 13-year species, one of which was discovered in Brood XIX in 1998 by scientists listening to cicada songs.
, and then dies off in several weeks.
In 1907, entomologist C. L. Marlatt
postulated the existence of 30 different broods of periodical cicadas: 17 distinct broods with a 17-year life cycle, to which he assigned Roman numerals I through XVII (with emerging years 1893 through 1909); plus 13 broods with a 13-year cycle, to which he assigned Roman numerals XVIII through XXX (1893 through 1905). Many of these hypothetical broods, however, have not been observed. Today only 15 are recognized.
Brood XIX is one of three extant broods of 13-year cicadas. The other two are Broods XXII and XIII, expected to re-emerge in 2014 and 2015 respectively. A fourth 13-year brood, Brood XXI (The Floridian Brood) was last recorded in 1870 in the Florida panhandle, but is believed to be now extinct.
(Walsh and Riley, 1868), Magicicada tredecassini
(Alexander and Moore, 1962), Magicicada tredecula (Alexander and Moore, 1962), and the recently discovered Magicicada neotredecim
(Marshall and Cooley, 2000). 2011 is the first appearance of Brood XIX since the discovery of the new species, which was first observed in this brood in 1998 when scientists observed an unexpected peak of acoustical frequencies in the brood's song.
The two species M. tredecim and M. neotredecim have an unusual geographical relationship in Brood XIX, with only a slight overlap between them, in a narrow band from northern Arkansas to southern Indiana. The other 13-year species occur together throughout the brood range, so in most parts of the range only three of the four species are present. All four 13-year species have distinct male calling songs, but the songs of M. tredecim and M. neotredecim in their narrow range of overlap show reproductive character displacement (RCD) that makes them even more distinct. (RCD functions to prevent reproductive overlap.) RCD is particularly noticeable in Brood XIX.
For Brood XIX in Alabama, adults of M. tredecula are less common than those of M. tredecim and M. tredecassini.
is gathering reports from the public about the geographical distribution of Brood XIX as part of a larger project to remap the distribution of Magicicada. Older maps show occurrences of Brood XIX cicadas in Missouri, Arkansas, Louisiana, Mississippi, Tennessee, Kentucky, Indiana, Maryland, Virginia, North Carolina, South Carolina, and Georgia
Across most of the range of Brood XIX, one observes M. tredecim in the southern regions and M. neotredecim in more northern ones, with some overlap in the westernmost region (mostly Missouri and Illinois).
, Texas, North Carolina
, Missouri
, Tennessee
and Maryland
. The next three appearances will be in 2024, 2037 and 2050.
News reports of the cicadas' emergence in Illinois included links to a video showing holes in the ground left by larval emergence, an adult cicada breaking out of its larval shell, and massed adult cicadas marching up tree trunks.
By June 8, 2011, a North Carolina newspaper reported that adult cicadas, which typically live for about a month, were dying en masse. Nymphs from eggs that have been laid by Brood XIX females will emerge from the earth again in 2024, to restart the cycle.
Magicicada
Magicicada is the genus of the 13- and 17-year periodical cicadas of eastern North America. They are sometimes called "17-year locusts", although cicadas belong to order Hemiptera, while locusts are Orthoptera....
, last seen in 1998 and reappearing in May and June of 2011 across a wide stretch of the southeastern United States. Periodical cicadas (Magicicada spp.) are often referred to as "17-year locusts" because most of the known distinct broods have a 17-year life cycle. Brood XIX is one of only three surviving broods with a 13-year cycle. It is also notable because it includes four different 13-year species, one of which was discovered in Brood XIX in 1998 by scientists listening to cicada songs.
Position among other broods of cicadas
Every 13 years, Brood XIX tunnels en masse to the surface of the ground, lays eggsEgg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
, and then dies off in several weeks.
In 1907, entomologist C. L. Marlatt
Charles Lester Marlatt
Charles Lester Marlatt was an American entomologist. Born in 1863 at Atchison, Kansas, he was educated at Kansas State Agricultural College , where he was assistant professor for two years...
postulated the existence of 30 different broods of periodical cicadas: 17 distinct broods with a 17-year life cycle, to which he assigned Roman numerals I through XVII (with emerging years 1893 through 1909); plus 13 broods with a 13-year cycle, to which he assigned Roman numerals XVIII through XXX (1893 through 1905). Many of these hypothetical broods, however, have not been observed. Today only 15 are recognized.
Brood XIX is one of three extant broods of 13-year cicadas. The other two are Broods XXII and XIII, expected to re-emerge in 2014 and 2015 respectively. A fourth 13-year brood, Brood XXI (The Floridian Brood) was last recorded in 1870 in the Florida panhandle, but is believed to be now extinct.
Species present
Brood XIX includes all four different species of 13-year cicadas: Magicicada tredecimMagicicada tredecim
Magicicada tredecim is a 13-year species of periodical cicada, closely related to the newly discovered 13-year species Magicicada neotredecim, from which it differs in its in male song pitch, female song pitch preferences, abdomen color, and mitochondrial DNA. Both M. tredecim and M. neotredecim...
(Walsh and Riley, 1868), Magicicada tredecassini
Magicicada tredecassini
Magicicada tredecassini is a species of periodical cicada endemic to the United States. It has a 13-year lifecycle but is otherwise indistinguishable from the 17-year periodical cicada Magicicada cassini...
(Alexander and Moore, 1962), Magicicada tredecula (Alexander and Moore, 1962), and the recently discovered Magicicada neotredecim
Magicicada neotredecim
Magicicada neotredecim is the most recently discovered species of periodical cicada. Like all Magicicada species, M. neotredicim has reddish eyes and wing veins and a black dorsal thorax. It has a 13-year life cycle but seems to be most closely related to the 17-year species Magicicada septendecim...
(Marshall and Cooley, 2000). 2011 is the first appearance of Brood XIX since the discovery of the new species, which was first observed in this brood in 1998 when scientists observed an unexpected peak of acoustical frequencies in the brood's song.
The two species M. tredecim and M. neotredecim have an unusual geographical relationship in Brood XIX, with only a slight overlap between them, in a narrow band from northern Arkansas to southern Indiana. The other 13-year species occur together throughout the brood range, so in most parts of the range only three of the four species are present. All four 13-year species have distinct male calling songs, but the songs of M. tredecim and M. neotredecim in their narrow range of overlap show reproductive character displacement (RCD) that makes them even more distinct. (RCD functions to prevent reproductive overlap.) RCD is particularly noticeable in Brood XIX.
For Brood XIX in Alabama, adults of M. tredecula are less common than those of M. tredecim and M. tredecassini.
Geographical distribution
Most maps of cicada distribution originate from 19th-century compilations that may show ranges much wider than those of current broods. The National Geographic SocietyNational Geographic Society
The National Geographic Society , headquartered in Washington, D.C. in the United States, is one of the largest non-profit scientific and educational institutions in the world. Its interests include geography, archaeology and natural science, the promotion of environmental and historical...
is gathering reports from the public about the geographical distribution of Brood XIX as part of a larger project to remap the distribution of Magicicada. Older maps show occurrences of Brood XIX cicadas in Missouri, Arkansas, Louisiana, Mississippi, Tennessee, Kentucky, Indiana, Maryland, Virginia, North Carolina, South Carolina, and Georgia
Across most of the range of Brood XIX, one observes M. tredecim in the southern regions and M. neotredecim in more northern ones, with some overlap in the westernmost region (mostly Missouri and Illinois).
2011 emergence
In early May 2011, cicadas began emerging throughout an area roughly enclosed by GeorgiaGeorgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
, Texas, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
and Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
. The next three appearances will be in 2024, 2037 and 2050.
News reports of the cicadas' emergence in Illinois included links to a video showing holes in the ground left by larval emergence, an adult cicada breaking out of its larval shell, and massed adult cicadas marching up tree trunks.
By June 8, 2011, a North Carolina newspaper reported that adult cicadas, which typically live for about a month, were dying en masse. Nymphs from eggs that have been laid by Brood XIX females will emerge from the earth again in 2024, to restart the cycle.
External links
- "Brood XIX (13-year), http://hydrodictyon.eeb.uconn.edu/projects/cicada/magicicada_central/about/brood_pages/broodXIX.php
- Cicada Mania http://www.cicadamania.com/cicadas/
- "Magicicada Broods", http://hydrodictyon.eeb.uconn.edu/projects/cicada/magicicada_central/about/brood_pages/broods.php
- More, Thomas, Singing Insects of North America, University of Florida map
- Post, Susan L. The Trill of a Life Time, photographs by Michael R. Jeffords, The Illinois Steward, Spring 2004. http://www.inhs.uiuc.edu/highlights/periodicalCicada.html
- Video of emerging Brood XIX cicadas in Illinois, 2011
- Video of Brood XIX cicadas responding to the saxophone playing of David RothenbergDavid RothenbergDavid Rothenberg is a professor of philosophy and music at the New Jersey Institute of Technology, with a special interest in animal sounds as music...