Green darner

Last updated

Green darner
Anax junius.JPG
Adult female, Blackwell Forest Preserve, Illinois [1]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Odonata
Infraorder: Anisoptera
Family: Aeshnidae
Genus: Anax
Species:
A. junius
Binomial name
Anax junius
(Drury, 1773)
Synonyms [3] [4]
  • Libellula juniaDrury, 1773
  • Anax spiniferusRambur, 1842
  • Anax ocellatusHagen, 1867
  • Anex junius(Drury)
  • Gomphus junius(Drury, 1773)
  • Anax severusHagen, 1867

The green darner or common green darner [5] (Anax junius), after its resemblance to a darning needle, is a species of dragonfly in the family Aeshnidae. One of the most common and abundant species throughout North America, it also ranges south to Panama. [6] It is well known for its great migration distance from the northern United States south into Texas and Mexico. [7] [8] It also occurs in the Caribbean, Tahiti, and Asia from Japan to mainland China. [9] It is the official insect for the state of Washington in the United States.

Contents

The green darner is a large dragonfly; males grow to 76 mm (3.0 in) in length with a wingspan up to 80 mm (3.1 in). [9] [10]

Females oviposit in aquatic vegetation, eggs laid beneath the water surface. Nymphs (naiads) are aquatic carnivores, feeding on insects, tadpoles, and small fish. Adult darners catch insects on the wing, including ant alates, moths, mosquitoes, and flies.

Taxonomy

Dru Drury described this species as Libellula junius in 1773. [11] There are not currently any recognized subspecies. There are three recognized synonyms: Anax spiniferus Rambur, 1842; Anax ocellatus Hagen, 1867; Anax severus Hagen, 1867. [3]

Distribution

Common green darners are commonly found throughout the continental United States and southern Canada, occasionally ranging as far south as Panama, particularly in the winter. [12] There are also populations in Hawaii and the Caribbean. Vagrant individuals have been seen far outside of their normal range including sightings in Alaska, Russia, China, Japan, France, the United Kingdom, India, and Bermuda. These vagrant sightings are likely migrating individuals blown off-course by strong winds or storms. [9]

Characteristics

Common green darners are large dragonflies, ranging from 6.8 to 8 centimetres (2.7 to 3.1 in) [13] in length and a wingspan of up to 10 centimetres (3.9 in). [12] Both sexes have an unmarked green thorax. Mature males have bluish-purple abdomens (the first few abdominal segments are the brightest) with a black dorsal stripe that broadens near the end of the abdomen. Immature males and most females have reddish-brown abdomens, but some females are patterned like adult males. Wings are initially clear but usually become amber-tinted with age, especially in females. [12] [9] Both sexes have a black ‘bulls-eye’ mark on the face (more precisely, the frons) in front of their eyes, a distinguishing field mark that separates them from the superficially similar comet darner ( Anax longipes ). [14] [12] This species oviposits in tandem which is a unique behavior among North American darners. [14] [12]

Natural history

Diet and predators

Both the adult and the nymphal stage are predators. Nymphs prey upon immature aquatic insects (including conspecifics), small crustaceans, small tadpoles, and even small fish. Adults primarily prey on winged insects, including wasps, flies, butterflies, and other Odonates. The primary predators of common green darner nymphs are fish. Adults are preyed upon by birds and occasionally robber flies, spiders, and other large dragonflies. [9]

Habitat

Nymphs develop in lakes, ponds, and slow streams and rivers. [12] Adults are most frequently seen around nymph habitat but they are strong fliers and can be found in a wide variety of habitats including grasslands, forests, and urban areas. [9]

Migration

There are several species of migratory dragonflies in North America, but common green darners are the best studied. [15] Other migratory species include:

The large geographic range and migratory behavior of the common green darner has made it a challenge to piece together its complex life history. Recent research has indicated that the annual life cycle of Anax junius is likely composed of at least three different generations. [8] The first generation emerges in the southern end of its range in early spring and migrates northwards through spring and summer. The second generation emerges in the northern end of its range in summer and migrates southwards in fall. The third generation occurs in the south during the winter and does not migrate. Common green darners migrate in fall and spring but for several reasons the southward movement in fall is more noticeable. [15]  

By attaching micro-radio transmitters to common green darners, researchers have found them to be capable of migrating up to 140 kilometres (87 mi) in a day, though they typically cover less distance per day. A group of researchers used stable isotope analysis on individuals collected between Ontario and Mexico during fall and documented that >90% of individuals moved southward, with an average distance of 900 kilometers. [15]

A study published in 2019 attached miniaturized radio transmitters to common green darners in the Great Lakes region and tracked their movement with the Motus Wildlife Tracking System. Individuals moved at an average groundspeed of 16 kilometres per hour (9.9 mph). [16]

Related Research Articles

<span class="mw-page-title-main">Odonata</span> Order of insects that includes the dragonflies and damselflies

Odonata is an order of predatory flying insects that includes the dragonflies and damselflies. The two groups are distinguished with dragonflies usually being bulkier with large compound eyes together and wings spread up or out at rest, while damselflies are usually more slender with eyes placed apart and wings folded together along body at rest. Adult odonates can land and perch, but rarely walk.

<span class="mw-page-title-main">Dragonfly</span> Predatory winged insects

A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threatens dragonfly populations around the world. Adult dragonflies are characterised by a pair of large, multifaceted, compound eyes, two pairs of strong, transparent wings, sometimes with coloured patches, and an elongated body. Many dragonflies have brilliant iridescent or metallic colours produced by structural coloration, making them conspicuous in flight. An adult dragonfly's compound eyes have nearly 24,000 ommatidia each.

<span class="mw-page-title-main">Damselfly</span> Suborder of insects

Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies but are usually smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Late Jurassic, and are found on every continent except Antarctica.

<span class="mw-page-title-main">Aeshnidae</span> Family of dragonflies

The Aeshnidae, also called aeshnids, hawkers, or darners, is a family of dragonflies, found nearly worldwide. The family includes some of the largest dragonflies.

<span class="mw-page-title-main">Common whitetail</span> Species of dragonfly

The common whitetail or long-tailed skimmer is a common dragonfly across much of North America, with a striking and unusual appearance. The male's chunky white body, combined with the brownish-black bands on its otherwise translucent wings, give it a checkered look. Females have a brown body and a different pattern of wing spots, closely resembling that of female Libellula pulchella, the twelve-spotted skimmer. Whitetail females can be distinguished by their smaller size, shorter bodies, and white zigzag abdominal stripes; the abdominal stripes of L. puchella are straight and yellow.

<span class="mw-page-title-main">Emperor (dragonfly)</span> Species of dragonfly

The emperor dragonfly or blue emperor is a large species of hawker dragonfly of the family Aeshnidae. It is the bulkiest dragonfly in most of Europe, including the United Kingdom, although exceeded by the magnificent emperor and in length by females of the golden-ringed dragonfly.

<i>Pantala flavescens</i> Species of dragonfly

Pantala flavescens, the globe skimmer, globe wanderer or wandering glider, is a wide-ranging dragonfly of the family Libellulidae. This species and Pantala hymenaea, the "spot-winged glider", are the only members of the genus Pantala. It was first described by Johan Christian Fabricius in 1798. It is considered to be the most widespread dragonfly on the planet, with good population on every continent except Antarctica, although rare in Europe. Globe skimmers make an annual multigenerational journey of some 18,000 km ; to complete the migration, individual globe skimmers fly more than 6,000 km —one of the farthest known migrations of all insect species.

<span class="mw-page-title-main">Giant Hawaiian darner</span> Species of dragonfly

The giant Hawaiian darner, also known as the giant Hawaiian dragonfly or pinao, is a species of dragonfly in the family Aeshnidae. It is one of two species of dragonfly that is endemic to the Hawaiian Islands. It is found near streams and wetlands on all islands of the archipelago and it has a wide altitude range, but is particularly common at higher elevations.

<span class="mw-page-title-main">Cordulegastridae</span> Family of dragonflies

The Cordulegastridae are a family of Odonata (dragonflies) from the suborder Anisoptera. They are commonly known as spiketails. Some vernacular names for the species of this family are biddie and flying adder. They have large, brown or black bodies with yellow markings, and narrow unpatterned wings. Their bright eyes touch at a single point, and they can be found along small, clear, woodland streams, flying slowly 30 to 70 cm above the water. When disturbed, however, they can fly very rapidly. They usually hunt high in forest vegetation, and prefer to capture prey resting on leaves or branches.

<i>Erythemis simplicicollis</i> Species of dragonfly

Erythemis simplicicollis, the eastern pondhawk, also known as the common pondhawk, is a dragonfly of the family Libellulidae, native to the eastern two-thirds of the United States and southern Ontario and Quebec, Canada. It is a dragonfly of ponds and still waters. The species is distinguished in that the female is bright green with a banded abdomen and the mature male has a blue abdomen with a green face and green and blue thorax.

<span class="mw-page-title-main">Blue dasher</span> Species of dragonfly

The blue dasher is an insect of the skimmer family. It is the only species in the genus Pachydiplax. It is very common and widely distributed through North America and into the Bahamas.

<i>Sympetrum vicinum</i> Species of dragonfly

Sympetrum vicinum, the Yellow-Legged Meadowhawk is one of some fifteen North American species of autumn meadowhawk, which are members of the Odonate family Libellulidae. It grows to 26–35 mm long.

<span class="mw-page-title-main">Gray sanddragon</span> Species of dragonfly

Progomphus borealis is a species of dragonfly in the family Gomphidae. This dragonfly species is commonly known as the gray sanddragon.

<i>Gomphurus externus</i> Species of dragonfly

Gomphurus externus, the plains clubtail, is a species of dragonfly in the family Gomphidae.

<i>Anax parthenope</i> Species of dragonfly

Anax parthenope, the lesser emperor, is a dragonfly of the family Aeshnidae. It is found in Southern Europe, North Africa, Middle East and Asia.

<i>Aeshna canadensis</i> Species of dragonfly

Aeshna canadensis, the Canada darner, is a species of dragonfly in the family Aeshnidae. It is common throughout southern Canada and the northern United States.

<i>Anax</i> (dragonfly) Genus of dragonflies

Anax is a genus of dragonflies in the family Aeshnidae. It includes species such as the emperor dragonfly, Anax imperator.

<i>Xanthocnemis zealandica</i> Species of damselfly

Xanthocnemis zealandica, commonly known as common redcoat damselfly, red damselfly, or red coat damselfly, is one of the most common native New Zealand damselflies. Adult damselflies are often seen flying around vegetation close to streams.

Odonata are insects with an incomplete metamorphosis (hemimetabolous). The aquatic larva or nymph hatches from an egg, and develops through eight to seventeen instars before leaving the water and emerging as the winged adult or imago.

References

  1. Cirrus Digital Anax junius Archived 2016-03-03 at the Wayback Machine
  2. Paulson, D.R. (2018). "Anax junius". IUCN Red List of Threatened Species . 2018: e.T165081A65831504. doi: 10.2305/IUCN.UK.2018-1.RLTS.T165081A65831504.en . Retrieved 28 July 2023.
  3. 1 2 "Common Green Darner". Project BioLib. 2023. Retrieved 28 July 2023.
  4. "Anax junius Drury, 1773". Global Biodiversity Information Facility . Retrieved 28 July 2023.
  5. Dunkle, Sidney W. (2000). Dragonflies through Binoculars: A Field Guide to Dragonflies of North America. Oxford University Press. p. 33. ISBN   978-0-19-972729-2.
  6. Eaton, Eric R.; Kaufman, Kenn (2006). Kaufman Field Guide to Insects of North America. Houghton Mifflin Company. p. 42. ISBN   978-0-618-15310-7.
  7. Evans, Arthur V. (2007). Field Guide to Insects and Spiders of North America. Sterling Publishing Co., Inc. p. 62. ISBN   978-1-4027-4153-1.
  8. 1 2 Hallworth, Michael T.; Marra, Peter P.; McFarland, Kent P.; Zahendra, Sara; Studds, Colin E. (2018). "Tracking dragons: stable isotopes reveal the annual cycle of a long-distance migratory insect". Biology Letters . 14 (12): 20180741. doi:10.1098/rsbl.2018.0741. PMC   6303508 . PMID   30958242.
  9. 1 2 3 4 5 6 Miner, Angela (2014). Martina, Leila Siciliano (ed.). "Anax junius". Animal Diversity Web. Retrieved 28 July 2023.
  10. Hahn, Jeffrey (2009). Insects of the North Woods. Kollath+Stensaas Publishing. p. 16. ISBN   978-0-9792006-4-9.
  11. "World Odonata List · University of Puget Sound". www2.pugetsound.edu. Archived from the original on 2021-10-05. Retrieved 2021-11-07.
  12. 1 2 3 4 5 6 Paulson, Dennis (2012). Dragonflies and Damselflies of the East. Princeton, New Jersey: Princeton University Press.
  13. "Species Anax junius - Common Green Darner". bugguide.net. Retrieved 2021-10-26.
  14. 1 2 "Wisconsin Odonata Survey: Anax junius". wiatri.net. Retrieved 2021-10-26.
  15. 1 2 3 4 May, Michael L. (2013-02-01). "A critical overview of progress in studies of migration of dragonflies (Odonata: Anisoptera), with emphasis on North America". Journal of Insect Conservation. 17 (1): 1–15. doi: 10.1007/s10841-012-9540-x . S2CID   15916175.
  16. Knight, Samantha M.; Pitman, Grace M.; Flockhart, D. T. Tyler; Norris, D. Ryan (2019-07-26). "Radio-tracking reveals how wind and temperature influence the pace of daytime insect migration". Biology Letters. 15 (7): 20190327. doi:10.1098/rsbl.2019.0327. PMC   6684972 . PMID   31266418.

Commons-logo.svg Media related to Anax junius at Wikimedia Commons