Green-eyed hawker | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Odonata |
Infraorder: | Anisoptera |
Family: | Aeshnidae |
Genus: | Aeshna |
Species: | A. isoceles |
Binomial name | |
Aeshna isoceles (Muller, 1767) | |
Range of Aeshna isoceles |
Aeshna isoceles is a small hawker dragonfly that is found in Europe, mostly around the Mediterranean, and the lowlands of North Africa. Its common name in English is green-eyed hawker. In Britain it is a rare and local species and is known as the Norfolk hawker. It has a brown colour with green eyes and clear wings and also a yellow triangular mark on the second abdominal segment which gave rise to its scientific name. It used to be in the genus Anaciaeschna as it has several differences from the other members of the genus Aeshna . Its specific name is often spelt isosceles.
A. isoceles is one of only two brown hawkers found in Europe, the other is A. grandis . Both have a brown thorax and abdomen but A. isoceles has green eyes and clear wings and a diagnostic yellow triangular mark on the second abdominal segment. The hindwings have an amber patch at their base. In contrast A. grandis has yellowish wings and blueish eyes. The green eye of A. isoceles stands out even in flight and in practice it is not difficult to tell these two dragonflies apart. In addition to the morphological differences A. isoceles is on the wing much earlier in the year than A. grandis .
A. isoceles is found in central Europe and around the Mediterranean and, the lowlands of North Africa. It is more common in eastern Europe than the south western Europe; it occurs in Spain and Portugal but is local.
It is found in wet areas, ponds, ditches and marshes, with dense vegetation and, in studies carried out in England, was found to be associated with Water-soldier (Stratiotes aloides).
The Norfolk hawker has always been a scarce and local insect in Britain. It used to be found in the Cambridgeshire fens but by the early 1980s the populations had greatly declined. It is now confined to relatively unpolluted fens and grazing marshes in the Broadlands of Norfolk and north-east Suffolk. [2] It can be found in Hickling Broad and two national nature reserves: Mid-Yare NNR and Ludham - Potter Heigham NNR and at Castle Marshes in the Barnby Broad and Marshes SSSI. Since 2011 the species has also been recorded in the Stour valley in east Kent [3] where egg laying has been observed and it appears to be spreading. It is protected under Schedule 5 of the Wildlife and Countryside Act 1981 [4] and listed in Category 1 (endangered) in the British Red Data Books on Insects. [5]
It is one of the earliest Aeshna dragonflies to be on the wing with a flight period from May to August. Adults do not spend as much time on the wing as other Aeshnas. Males will fly around over a stretch of water defending a territory and if the pond is small the male will hover over the centre of the pond. Unlike other aeshnas, where the adults seem to be continuously on the wing beating up and down their territory, male A. isoceles come to rest on vegetation from time to time. Females oviposit onto plants and the eggs hatch in about 2 weeks. Larval development takes 2 years.
This species was first described as Libellula quadrifasciata, var. 36. isoceles by Muller in 1764. It has since been called Aeshna rufescens and Aeshna chysophthalmus and more recently Anaciaeschna isoceles. It is by this last name that it is referred to in many books. It has since been included into the genus Aeshna and in many books is called Aeshna isoceles: however the original specific name was isosceles. Dijkstra and Lewington (2006) and Boudot JP., et al. (2009) both call it Aeshna isoceles whereas Askew, R.R. (2004),and earlier books, refer to it as Aeshna isosceles.
Aeshna, or the mosaic darners, is a genus of dragonflies from the family Aeshnidae. Species within this genus are generally known as "hawkers" or "darners".
The migrant hawker is one of the smaller species of hawker dragonflies. It can be found away from water but for breeding it prefers still or slow-flowing water and can tolerate brackish sites. The flight period is from July to the end of October. A. mixta occurs in North Africa, southern and central Europe to the Baltic region.
The red-veined darter or nomad is a dragonfly of the genus Sympetrum.
Libellula depressa, the broad-bodied chaser or broad-bodied darter, is one of the most common dragonflies in Europe and central Asia. It is very distinctive with a very broad flattened abdomen, four wing patches and, in the male, the abdomen becomes pruinose blue.
The common darter is a dragonfly of the family Libellulidae native to Eurasia. It is one of the most common dragonflies in Europe, occurring in a wide variety of water bodies, though with a preference for breeding in still water such as ponds and lakes. In the south of its range adults are on the wing all year round.
The southern hawker or blue hawker is a species of hawker dragonfly.
Anaciaeschna is a genus of dragonflies in the family Aeshnidae. Species of Anaciaeschna are found in Africa, Asia and Australia.
Tramea basilaris, also known as the keyhole glider, red marsh trotter, or wheeling glider, is a species of dragonfly in the family Libellulidae. It is found throughout most of Africa, Arabia and in Asia. Capable of very long migration and nomadic flight, it reached Europe once, being recorded at the island of Linosa, Sicily (Italy) in 2016. Similarly, this species is able to use the trade winds to reach the Caribbean and South Americas, where it was caught in Suriname, "guadeloupe" and "martinique".
Trithemis kirbyi, also known as the Kirby's dropwing,orange-winged dropwing, or scarlet rock glider is a species of dragonfly in the family Libellulidae.
The blue-spotted hawker is the only known species of dragonfly of the genus Adversaeschna in the family Aeshnidae.
Lestes macrostigma is a species of damselfly of the family Lestidae, the spreadwings. It is known by the common name dark spreadwing. It is native to much of southern Europe, its distribution extending into western Asia.
Aeshna affinis, the southern migrant hawker or blue-eyed hawker, is a dragonfly found in southern Europe and Asia. It is in the family Aeshnidae and is very similar in appearance to A. mixta.
Anax parthenope, the lesser emperor, is a dragonfly of the family Aeshnidae. It is found in Southern Europe, North Africa, Middle East and Asia.
Chalcolestes viridis, formerly Lestes viridis, is a damselfly of the family Lestidae. It has a metallic green body and at rest it holds its wings away from its body. Its common name is the willow emerald damselfly or the western willow spreadwing. It has an elongated abdomen and pale brown spots on its wings and resides in areas of still water with overhanging trees.
The Persian damselfly or Dumont's bluetail is a damselfly, belonging to the family Coenagrionidae.
Epallage fatime, the Oriental damselfly, is a damselfly (Zygoptera) from the family of the Euphaeidae.