Australian emperor

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Australian emperor
Australian Emperor in flight.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Odonata
Infraorder: Anisoptera
Family: Aeshnidae
Genus: Anax
Species:
A. papuensis
Binomial name
Anax papuensis
(Burmeister, 1839) [2]
Anax papuensis distribution map.svg
Synonyms [3]
  • Aeschna papuensisBurmeister, 1839
  • Anax congenerRambur, 1842
  • Hemianax papuensis(Burmeister, 1839)

The Australian emperor dragonfly, [4] also known as the yellow emperor dragonfly, [5] the Baron Dragonfly in New Zealand, [6] scientific name Anax papuensis, is a species of dragonfly in the Aeshnidae family. [3] It is black with yellow dots along its tail. [7]

Contents

Description

Female Australian emperor. Hemianax papuensis Sydney.jpg
Female Australian emperor.

The Australian emperor is a very large dragonfly, up to 70 mm long. Its abdomen is marked boldly in black and yellow. The thorax is greenish-grey. The head is yellow with a T-shaped mark on the forehead (frons). The eyes are yellow-green. The leading edges of the wings are yellow. The insect habitually hunts fairly slowly, patrolling up and down like other hawkers, with short bursts at high speed. [8]

Their wingspan is 11 centimetres (4.3 in). Males and females are similar. [9]

Distribution and habitat

The Australian emperor is found throughout Australia. In the state of Victoria, it has a split distribution: below about 600 metres in altitude, and above about 1200 metres, apparently because it avoids forested areas. It is also found in New Zealand, New Guinea, the Cocos-Keeling Islands, Java, Sumba and New Caledonia. [10] [11]

The Australian emperor is widespread and common on larger bodies of water with tall vegetation on the banks. Like other hawkers, it may hunt far from water. It flies throughout the summer from September to May. [8]

Behaviour

Australian emperor laying eggs, guarded by the male in tandem position Australian Emperor mating and laying.jpg
Australian emperor laying eggs, guarded by the male in tandem position

The Australian emperor is notable as the dragonfly in which motion camouflage was studied by Mizutani et al.: males of Anax papuensis are fiercely territorial, and approach and attack rivals, the males choose a flight path that keeps their image as seen by the target still with respect to a landmark point. The attacking dragonfly thus looms larger in the target's eyes, but otherwise does not seem to move until it is very close. [12] [13] [14]

The males are very protective of their females. In case of intrusion of another individual, he will drive it away by engaging in a series of noisy air battles. Females lay their eggs under water. [5]

Bibliography

See also

References

  1. Rowe, R. (2017). "Anax papuensis". IUCN Red List of Threatened Species . 2017: e.T197096A83372051. doi: 10.2305/IUCN.UK.2017-1.RLTS.T197096A83372051.en . Retrieved 20 November 2021.
  2. Burmeister, Hermann (1839). Handbuch der Entomologie (in Latin and German). Vol. 2. Berlin: T.C.F. Enslin. pp. 805–862 [841] via Biodiversity Heritage Library.
  3. 1 2 "Species Anax papuensis (Burmeister, 1839)". Australian Faunal Directory . Australian Biological Resources Study. 2012. Retrieved 23 January 2017.
  4. "Common name". Brisbane Insects. Retrieved April 27, 2012.
  5. 1 2 "Second common name and habitat". Oocities. Retrieved April 27, 2012.
  6. "Baron dragonfly (Hemianax)". Landcare Research NZ. Retrieved 24 January 2025.
  7. "Colour". Archived from the original on 2012-03-27. Retrieved 2013-06-28.
  8. 1 2 Hemianax papuensis Retrieved 16 January 2012
  9. Description Archived April 26, 2013, at the Wayback Machine
  10. Esperance Fauna Retrieved 16 January 2012
  11. Theischinger, 2006.
  12. Hopkin, Michael (June 5, 2003). "Nature News" . Dragonfly Flight Tricks the Eye. Nature.com. doi:10.1038/news030602-10 . Retrieved January 16, 2012.
  13. Mizutani, A. K.; Chahl, J. S. & Srinivasan, M. V. (June 5, 2003). "Insect behaviour: Motion camouflage in dragonflies". Nature. 65 (423): 604. Bibcode:2003Natur.423..604M. doi: 10.1038/423604a . PMID   12789327.
  14. Glendinning, Paul (27 January 2004). "The mathematics of motion camouflage". Proceedings of the Royal Society of London. Series B: Biological Sciences. 271 (1538): 477–81. doi:10.1098/rspb.2003.2622. PMC   1691618 . PMID   15129957.