Damselfly for ID

[Purplepixii]

Hi
I've had one of these over my pond on and off for the past week or so but today I have two chasing each other.

I've been through my Dragonfly/Damselfly book and the closest match I can find is the Scarce Blue-tailed Damselfly (Ischnura pumilio). I'm hoping to get some more photos shortly and I'd like to know if I have ID'd this correctly or not please

Sarah

[Dogghound]

Its the Blue tailed damselfly Ischnura elegans, I.pumilio would be unusual in a garden pond.

[htcdude]

I'm probably wrong but it might be an Emerald Damselfly.

If your books fail, also try the BDS site:

Damselflies | british-dragonflies.org.uk

Nige

[wint]

I agree with dogghound. Note that female Scarce Blue-tails do not have a tail light on S8.

[Purplepixii]

Cheers all. If it is a female Ischnura elegans the closest image I've been able to find on the web is the bottom right on this link: Female forms of Ischnura elegans

Are we definitely sure this is it? Darn things are a nightmare to ID!

Sarah

[Dogghound]

Without doubt Ischnura elegans f.infuscans-obsoleta the adult form of rufescens. They occur in a wide variety of colour forms which is possibly causing the confusion with this one.

[htcdude]

Without being a pain can I ask what rules out female Emerald?

Thanks,

Nige

[Dogghound]

1. The resting position with the wings closed. Lestes tends to almost always rest with the wings open spread out (although some tenerals dont do this as often).
2. The pterostigma (Little black square in the top corner of the forewing) is two toned typical of Ischnura . Lestes have plain pterostigma which are longer.
3. Female Lestes have an almost split abdoment tip due to the ovipositor sheath. Here it is a blunt end with a vulvar scale.
4. The colour female L.sponsa are a washed out cream on the flanks and underside, this is quite yellow. It lacks and metallic green typical of Lestes.
5. The thorax lacks a broad metallic humeral stripe (suture). Lestes tends to have quite an extensive area of metallic green on the thorax, even when I.elegans has a humeral stripe its not as broad as Lestes.
6. The structure in comparsion to Ischnura, Lestes is very delicate with a long thin abdomen.

I hope this helps, if you get several images up you should see the differences, its not always easy with Ischnura as it has a variety of colour morphs.

[htcdude]

Helps very much thanks! I'm hoping to get a field guide for my birthday

Nige

[Purplepixii]

Thanks all, especially Dogghound for that explanation. It's amazing how varied in colours Ischnura can be - talk about making identification confusing!!

Of course it goes without saying that since I said I was going to get more photo's the darned things have been hiding from me!