Tergum

For a municipality in Algeria, seeTerga, Algeria.

Atergum(Latin for "the back";pl.:terga,associated adjectivetergal) is thedorsal('upper') portion of anarthropodsegment other than the head. Theanterioredge is called the 'base' and posterior edge is called the 'apex' or 'margin'. A given tergum may be divided into hardened plates orscleritescommonly referred to astergites.

Tergites (with lateral paranota) of apolydesmid millipede

In athoracicsegment, for example, the tergum may be divided into an anteriornotumand a posteriorscutellum.Lateral extensions of a tergite are known asparanota(Greek for "alongside the back" ) orcarinae(Latin for "keel" ), exemplified by the flat-backed millipedes of the orderPolydesmida.

Kinorhynchshave tergal and sternal plates too, though seemingly not homologous with those of arthropods.

Tergo-tergalis astridulatorymechanism in which fine spines of the abdominal tergites are rubbed together to produce sound.This process is known as abdominal telescoping.

Examples

• 
  Abdominal tergum (divided into several tergites) of abee.
• 
  Seven sclerites distinctly visible on the back of a pregnant scorpion.
• 
  A tergite of thiswaspis labeled 19.
• 
  Thoracic tergites of varioustrilobites.

See also

• Sternum (arthropod anatomy)

Further reading

• Hood, J. Douglas (1958). "The terms tergum and sternum, tergite and sternite".Systematic Zoology.7(3): 131–133.doi:10.2307/2411977.JSTOR2411977.