Cassini periodical cicadas
Encyclopedia
The name Cassini periodical cicadas is used to group two closely related species of periodical cicadas: Magicicada cassini
(Fisher, 1851) (sometimes also called Magicicada septemcassini because of its 17-year lifecycle), and Magicicada tredecassini
(Alexander and Moore, 1962), a species essentially identical except for its 13-year lifecycle.
The cassini males' courting behavior is unusual because large groups of cassini males may sing and fly together in synchrony
: that is, bursts of sound, as thousands of males sing in unison, alternate with silence, as clouds of flying cicadas leave perches in unison, seeking a new perch before the next ensemble song.
. The abdomen is black except for occasional faint orange-yellow marks on the ventral surface seen in some location.
In a typical brood of periodical cicadas, decim
and decula types will be present as well as cassini. The three different types have unique species song-types; they also tend to sing at different times of day, with cassini choruses most likely in mid- to late afternoon, later than decim or decula varieties. The cassini-type song consists of a series of ticks followed by a buzz; it has also been described as sounding like "someone trying to get a lawnmower started."
Magicicada males seek out sunlit vegetation, where they typically gather with conspecific males to form large choruses, alternating singing behavior with short flights. Cassini-type males are unusual in synchronizing these behaviors, so that thousands of males sing their mating song in unison and then fly together. according to Alexander and Moore (1958):
The "congregational" singing of males (so-called because it inspires both males and females to congregate) requires this synchrony in cassini-types for its success.
Cassini-type cicadas are most often found in deciduous lowland woods and flood plains, rather than the upland woods favored by other Magicicada.
Magicicada cassini
Magicicada cassini, sometimes called the dwarf cicada is a species of periodical cicada endemic to the United States. It has a 17-year lifecycle but is otherwise indistinguishable from the 13-year periodical cicada Magicicada tredecassini...
(Fisher, 1851) (sometimes also called Magicicada septemcassini because of its 17-year lifecycle), and 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), a species essentially identical except for its 13-year lifecycle.
The cassini males' courting behavior is unusual because large groups of cassini males may sing and fly together in synchrony
Synchronization
Synchronization is timekeeping which requires the coordination of events to operate a system in unison. The familiar conductor of an orchestra serves to keep the orchestra in time....
: that is, bursts of sound, as thousands of males sing in unison, alternate with silence, as clouds of flying cicadas leave perches in unison, seeking a new perch before the next ensemble song.
Description
All Magicicada species have a black dorsal thorax with red eyes and orange wing veins. Cassini periodical cicadas are smaller than decim periodical cicadasDecim periodical cicadas
Decim periodical cicadas is a term used to group three closely related species of periodical cicadas: Magicicada septendecim, Magicicada tredecim, and Magicicada neotredecim. M. septendecim, first described by Linnaeus, has a 17-year lifecycle; the name "septendecim" is Latin for 17. M...
. The abdomen is black except for occasional faint orange-yellow marks on the ventral surface seen in some location.
In a typical brood of periodical cicadas, decim
Decim periodical cicadas
Decim periodical cicadas is a term used to group three closely related species of periodical cicadas: Magicicada septendecim, Magicicada tredecim, and Magicicada neotredecim. M. septendecim, first described by Linnaeus, has a 17-year lifecycle; the name "septendecim" is Latin for 17. M...
and decula types will be present as well as cassini. The three different types have unique species song-types; they also tend to sing at different times of day, with cassini choruses most likely in mid- to late afternoon, later than decim or decula varieties. The cassini-type song consists of a series of ticks followed by a buzz; it has also been described as sounding like "someone trying to get a lawnmower started."
Magicicada males seek out sunlit vegetation, where they typically gather with conspecific males to form large choruses, alternating singing behavior with short flights. Cassini-type males are unusual in synchronizing these behaviors, so that thousands of males sing their mating song in unison and then fly together. according to Alexander and Moore (1958):
Almost every singing male in a woods containing tens of thousands of singers achieves synchrony with all the others, and the result gives the impression of a gigantic game of musical chairs. A treeful of these insects singing in synchrony is motionless when observed during the great burst of sound caused by insects buzzing together, and then becomes a frenzy of activity between buzzes with nearly every individual changing perches.
The "congregational" singing of males (so-called because it inspires both males and females to congregate) requires this synchrony in cassini-types for its success.
Habitat
Periodical cicadas live in roughly the southeastern quadrant of the United States. Cassini-type cicadas are especially common in the most southwestern populations.Cassini-type cicadas are most often found in deciduous lowland woods and flood plains, rather than the upland woods favored by other Magicicada.
Ecological impact
Egg-laying by a large brood may cause many twigs to die off but does little long-term harm to mature trees.External links
- Video of Brood XIXBrood XIXBrood XIX is the largest 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...
M. tredecassiniMagicicada tredecassiniMagicicada 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...
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...
, 2011 - Synchronized chorusing of M. tredecassini, 2011