Emperor (dragonfly)

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Emperor dragonfly
Male
Tenerife, Spain
female
Oxfordshire, England
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Odonata
Infraorder: Anisoptera
Family: Aeshnidae
Genus: Anax
Species:
A. imperator
Binomial name
Anax imperator
Leach, 1815
Synonyms[1]

The emperor dragonfly[2] or blue emperor[1] (Anax imperator) is a large species of hawker dragonfly of the family Aeshnidae. It is the bulkiest dragonfly in most of Europe, including the United Kingdom,[2] although exceeded by the magnificent emperor (A. immaculifrons – very marginal range in Europe)[3] and in length by females of the golden-ringed dragonfly (Cordulegaster boltonii – a species with an unusually long ovipositor).[4]

Nomenclature[edit]

The generic name Anax is from the ancient Greek ἄναξ, "lord";[5] the specific epithet imperator is the Latin for "emperor", from imperare, to command.[6]

Distribution[edit]

This dragonfly has a wide distribution; it is found throughout Africa and through most of Europe, the Arabian Peninsula, and south-western and central Asia.[1] Since the 1990s, its range has expanded in Europe, both northwards and to higher altitudes. For example, the first Scandinavian record was in 1994 in Denmark; in 2002 it was first recorded in Sweden and in 2004 first in Scotland; today it is regular in all three countries.[1][2][7]

Identification[edit]

The emperor dragonfly is a large and bulky species. It is 73–82 mm (2.9–3.2 in) long, with average being 78 mm (3.1 in) and males growing larger than females.[2][8] The average wingspan is 104 mm (4.1 in).[8] When they first emerge, both sexes appear pale green with brown markings. The legs are brown with a yellow like base. Wings are born black but grow yellow-brown when they grow. Males have a sky blue abdomen marked with a diagnostic black dorsal stripe and an apple green thorax. The thorax and head of a male is green and their prominent eyes are blue. Females have similar markings but they are mainly green.[9]

Behaviour[edit]

They frequently fly high up into the sky in search of prey, which includes butterflies, other Odonata and tadpoles; small prey is eaten while flying. They breed in a variety of aquatic habitats from large ponds to dikes, but they require a plentiful supply of vegetation in the water. The females lay the eggs into plants such as pondweed, and always lay alone. The larvae are very aggressive and are likely to influence the native species composition of colonized freshwater ecosystems.[7] The adult male is highly territorial, and difficult to approach.[9] In the summer months emperor dragonflies are frequent visitors to gardens, being especially prevalent in the southern counties of Great Britain.

References[edit]

  1. ^ a b c d e Mitra, A. (2016). "Anax imperator". IUCN Red List of Threatened Species. 2016: e.T59812A72311295. doi:10.2305/IUCN.UK.2016-3.RLTS.T59812A72311295.en. Retrieved 19 November 2021.
  2. ^ a b c d "Emperor". British Dragonfly Society. Retrieved 25 August 2010.
  3. ^ "Anax immaculifrons Rambur, 1842 – Magnificent Emperor". Dragonflies and Damselflies – in and around Europe. Retrieved 25 November 2023.
  4. ^ "Golden-ringed Dragonfly". British Dragonfly Society. Retrieved 25 November 2023.
  5. ^ Beekes, Robert (2010) [2009]. "S.v. ἄναξ". Etymological Dictionary of Greek. Vol. 1. With the assistance of Lucien van Beek. Leiden, Boston: Brill. pp. 98–99. ISBN 978-900417-418-4.
  6. ^ "imperator (n.)". Online Etymology Dictionary. Retrieved 27 August 2021.
  7. ^ a b Herzog, Rebecca; Osigus, Hans−Jürgen; Feindt, Wiebke; Schierwater, Bernd; Hadrys, Heike (29 October 2016). "The complete mitochondrial genome of the emperor dragonfly Anax imperator LEACH, 1815 (Odonata: Aeshnidae) via NGS sequencing". Mitochondrial DNA Part B. 1 (1): 783–786. doi:10.1080/23802359.2016.1186523. PMC 7799497. PMID 33473626.
  8. ^ a b "Anax imperator (Leach, 1815)". Insects of Britain and Ireland: dragonflies and damselflies (Odonata). Retrieved 25 November 2023.
  9. ^ a b "Emperor dragonfly videos, photos and facts — Anax imperator". ARKive. Archived from the original on 2015-04-09. Retrieved 2013-08-08.

External links[edit]