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"A Nature Observer′s Scrapbook"

Dragonflies - of the order Odonata.
Hawkers, Chasers, Darters and Damselflies
- and associated Mayflies.




Mayfly, Centroptilum luteolum Mayfly, Centroptilum luteolum

Mayfly sp.

Centroptilum luteolum
- several similar species.

In the classification of insects, Mayflies and Stoneflies are closely associated with the dragonfly families.

There are some 47 different species of Mayflies characterised by the way they hold their wings upright and their 2 or 3 long trailing 'tails'. A rough guide to identification can be guaged by wing length (6.5mm in this case) but precise identification often entails microscopic examination. They are found close to water as their larvae (nymphs) are aquatic.

In these images it is easier to identify the sex of the specimen than it is to identify the species. The males have large flat eyes as seen here, whereas the females have small 'normal' sized eyes. In the view from above (the dorsal view) it is just possible to see the very small almost insignificant, hind wings. Most Mayflies have four wings but in some, hind wings are not present at all.

Generally, Mayflies are on the wing from April through to September.



DateSighting
08.04.2007 Found on fence post some 30m from field drainage ditch.


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Migrant Hawker
Click for larger image. Migrant Hawker side view
Click for larger image.

Migrant Hawker

Aeshna mixta

I find that the majority of dragonflies tend to be somewhat skittish and require a lot of patience to get decent photographs. This species is the exception. I was able to take several closeup shots of two specimens and they never moved.

Despite it's common name, the Migrant Hawker has now taken up residence in the southern UK.

It flies from late July through to October and, although smaller (body length of 70mm), it could be confused with the Southern Hawker and the Common Hawker.

The key identifying features are the 'golf-tee' mark at the front of the abdomen and the well separated blue spots at the rear.

Much larger and clearer pictures can be seen by clicking the images on the right.



DateSighting
08.09.2005 Two specimens, one male, the other unidentified, visited the small garden pond.
23.08.2007 Female rested up on the Cupressus hedge for some time.


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Broad Bodied Chaser (f)

Broad-bodied Chaser

Libellula depressa

The three inch (75mm) diameter fence post gives a good scale for the wingspan of this female Broad Bodied Chaser. Body length is about 45mm.

This was the first time I had seen this species here and it was probably the new pond 'next door' which had attracted them. A pair spent 30 minutes patrolling the lea side of the hay meadow western hedge on a calm sunny morning. Only the female landed. They are normally on the wing from May to August.

Newly hatched, both sexes are pale yellow. As they mature, the head and thorax of both sexes turns brown. The broad central stripe of the female's abdomen darkens but the male's becomes slate blue with yellow side markings.


DateSighting
07.06.2004Female came to rest on fence post, while male patrolled overhead.



Black-tailed Skimmer f

Black-tailed Skimmer

Orthetrum cancellatum


The Black-tailed Skimmer's common name is taken from the coloration of the mature male of the species which has a blue-grey abdomen with a distinctive black tail patch. Like so many of the dragonflies, the sexes are 'dimorphic', meaning that the sexes can appear to be quite different to each other. The image seen here is of a mature gold and black female. But, the confusion does not stop there because immature males can look very similar to mature females! The outstretched wingspan can be about three inches, 75mm. Males can be very protective and will drive off other species thought to be threatening the females.


The species was originally confined to the south of England and Wales but is gradually encroaching northwards and is now not uncommon in Lincolnshire. I found this one on bare ground by the side of a flooded gravel pit, in a very agitated state being beset upon by ants. Once 'rescued' on a stick and removed from its tormentors, it settled down to compose itself and calmly posed for the camera.


The species is 'on the wing' between May and August. Mating takes place in flight or on the ground close to water. The larvae are aquatic and can take three years to fully develop.




DateSighting
19.05.2011 North end of Kirby Gravel Pits Nature Reserve.


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Common Darter

Common Darter

Sympetrum striolatum

I am easily confused by the colour of dragonflies. Nearly all of them change colour as they mature and just when I think I can recognise one species, I find that the opposite sex is quite a different colour. And the Common darter is no exception.

On hatching, both sexes are a pale yellow. The males then darken and turn a dark burnt orange colour. But the females retain their yellow colour through maturity and only darken with old age.

At 40mm body length, this is one of the smaller species but quite common throughout the UK, breeding in static water and flying from June to October.



DateSighting
Late July 1999 Seen at the Benniworth Springs conservation area pond


Common blue damselfly Common blue damselfly
detail

Common blue damselfly

Enellagma cyathigerum

Whereas all the larger dragonflies tend to rest with wings spread wide open, 'nearly all' the damselflies are seen at rest with wings tightly folded back over the abdomen.

And this can cause problems with identification of the 'blue damselflies'. There are five discrete blue damsel species with much the same black and blue abdominal bands. The significant difference between them lies in the shape of the foremost mark, just behind the thorax - which can be veiled by their folded wings.

The Common blue damsel is identified by the black 'spot' seen in the lower image. Other species can have a 'U' shape, a 'wineglass' shape, an 'arrowhead' or a mark which defies my powers of discription!

So, having found your damselfly at rest, normally on reeds growing out of water, you now have to get a good clear overhead view of it to have much chance of identifying it! It can get tricky.

On the other hand, if you find one you will usually find a lot. They are common and they are widespread throughout the UK. They have a body length of about 32mm and their normal flight period is from May to September.



DateSighting
Late July 1999 Seen at Benniworth Springs conservation area pond.


Blue-tailed damselfly Blue-tailed damselfly larva

Blue-tailed damselfly

Ischnura elegans

It is true that the male Blue-tailed damselfly with its black upper abdomen and one solitary blue band on abdomen segment 8 is unlikely to be confused with anything else but, the females try hard to to be different. They can come in three different colour forms - still with the black back but with yellow, blue or pale violet under-bellies and 'flashes' on the thorax.

Appearing early in May, they are one of the first dragonflies to hatch and can be found widespread throughout the UK until mid September. Like many other dragonfly species the larvae remain in an aquatic state for two years before pupating.

At only 31mm body length, they are amongst the smallest of the dragonfly order.

The 21mm aquatic larva (nymph) was found during a survey of a freshwater pool at the Gibraltar Point Nature Reserve and the small immature wing stubs can be clearly seen.



DateSighting
19.07.2005 On Iris leaf by back garden pond.
06.05.2006 Aquatic larva found during a pond survey at Gibraltar Point Reserve.
08.06.2006 South eastern corner of meadow, presumably drifted over from adjacent pond..


Dark mark like an
elongated thistle flower head.

Azure Damselfly

Coenagrion puella

My initial attempt at naming this green damselfly with its wings half open was to think it might be the Emerald damselfly. But, the apparent logic fell apart when it was pointed out that it was really a green female of the Azure damselfly species. Note the thin black lines on the side of the thorax which are missing from the Emerald.

Another giveaway feature of the Azure, green females, is that they have a black elongated 'thistle flower head' mark on segment two of the abdomen. With a bit of imagination, one can just about see the suggestion of this in this image. (Scroll the mouse over the upper abdomen.) But, beware, this is not common throughout the Azure species. A blue male sports a thin 'U' shape and a blue female has a mark like a caricature of a caucasian lady folk dancer (you have to see it to believe it) - usually referred to as a 'mercury' mark.



DateSighting
Late July 1999 Seen at Benniworth Springs conservation area pond.




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