Kingdom: Animalia
Phylum: Arthropoda Class: Insecta Order: Hemiptera Family: Cicadidae Genus: Tanna Species: T. japonensis Above: a molting (generic) cicada
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Description
T. japonensis is a cicada primarily found in Japan. They range from 21 to 38mm in length, with the males about 140% the size of females. They're mostly reddish brown, but have green around their eyes. In addition to the two prominent compound eyes, they have three small eyes (or ocelli) on the forehead. As insects, cicadas drive hemolymph through an open circulatory system[1, p688], and they have retained both pairs of ancestral wings; the anterior pair is membranous, and the posterior pair more leathery[1, p688-690]. Cicadas live off of tree sap, and reproductive periods may be as long as 17 years[2] (varies by species).
Reproduction
T. japonensis don't undergo complete metamorphosis[1, p689-690]. Their young hatch directly from eggs, and spend most of their lives growing through a series of molts[1, p689] underground, feeding on xylem sap from plant roots. The nymphs have strong front legs for digging[4]. When they emerge, they ecdyse for the final time, producing wings, becoming fully grown and ready to mate[4].
Sound
Male cicadas are among the loudest insects in the world[3]. They produce their mating call by contracting an internal muscle which pulls a portion of their exoskeleton, the tymbal, a ribbed membranous structure (one on either side of the abdomen)[2][5]. This results in an inward buckling motion which produces clicks from the ribs, and releasing them produces another click[2]. The cicadas large, mostly hollow abdomin amplifies the sound[2]. The same apparatus is also the cicadas ear, and the males disable their ability to hear while calling[3]. T. japonensis cries are most often heard in the morning or evening in Japan.
Evolution
The earliest insect fossils known are from the Devonian. Flight evolved in insects in the Carboniferous, and many species developed mouthparts for feeding on gymnosperms[1, p688]. As cicadas feed exclusively on products of plant vascular systems (and don't interact with any angiosperm reproductive structures) it could be possible they emerged with or shortly after vascular plants or gymnosperms[speculation].
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The parasitic moth Epipomponia nawai uses T. japonensis as a host for its eggs
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References
[1]Campbell & Reece, Biology 8th Edition
[2]Edoh, K., Hughes, D., & Katz, R. (2013). Nonlinearity In Cicada Sound Signals. Journal Of Biological Systems, 21(1), 1-13. doi:10.1142/S0218339013500046
[3]http://web.archive.org/web/20061004162419/http://www.5050.co.za/inserts.asp?ID=3234
[4]http://wannabeentomologist.com/tag/cicada/
[5]http://www.mnh.si.edu/highlight/cicadas/pages/tymbal.htm
[2]Edoh, K., Hughes, D., & Katz, R. (2013). Nonlinearity In Cicada Sound Signals. Journal Of Biological Systems, 21(1), 1-13. doi:10.1142/S0218339013500046
[3]http://web.archive.org/web/20061004162419/http://www.5050.co.za/inserts.asp?ID=3234
[4]http://wannabeentomologist.com/tag/cicada/
[5]http://www.mnh.si.edu/highlight/cicadas/pages/tymbal.htm
Further reading
(didn't get to use it since I couldn't find how long T. japonensis life cycle is, but it's good)
(didn't get to use it since I couldn't find how long T. japonensis life cycle is, but it's good)
[4]http://sciencenetlinks.com/science-news/science-updates/cicada-cycles/