Graeme's picture

Dragonfly larvae

Observed: 16th May 2010 By: Graeme
The Anton River Conservation Association
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Emperor Dragonfly (Anax imperator). Larvae.Rooksbury Mill.Wild Trek Pond Dip 16.5.10.jpg
Description:

Found on pond dip at local lakes.

Identifications
Species interactions

No interactions present.

Comments

Dioctria's picture

Brown Hawker?

I think this might be one of the Hawkers (Aeshna), probably Brown or Southern.

I've just bought Steve Cham's guide to dragonfly larvae and exuviae so this is my first attempt to try it out! The head doesn't appear rounded enough for an Emperor. Most of the visible features fit Brown Hawker (Aeshna grandis) including the pale stripe on the sides of the thorax and head, banded leg colouring and head shape. However, it should have a "definite lateral spine on S6" which I don't see. They are very clear on segments 7-9. Going by the pale stripe though, which is described as "characteristic", I'll suggest Brown Hawker.

(You didn't get a shot of the underside of the head did you? There are some features there which would settle it.)

David

Matt Smith's picture

Spines on S6

I don't see any spines on Segment 6, which would seem to rule out Brown Hawker, leg banding or not.

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Dioctria's picture

Tricky

Indeed. In the end I went with the presence of the characteristic pale markings rather than the absence of the spines. But these two features seem to be in conflict here and I wasn't sure which should receive most weight.

David

Dioctria's picture

Reconsidering...

Thinking about it Matt, you're obviously right to give more weight to a morphological feature over colouration. In which case it would be Azure, Common or one of the Emperors. What put me off Emperor at the start was the strongly curved hind margin of the eye, but that and the head shape may just be down to the angle of view which is more oblique than I thought, so it may well be an Emperor as Graeme originally suggested. Apologies for the wild goose chase Graeme! :)

David

Matt Smith's picture

Emperor?

Don't think its an Emperor, the hind margin of the eyes is defintely wavey, which you don't see in Emperor larvae.

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RoyW's picture

Migrant or Southern Hawker.

I would prefer to have the opportunity to look at different angles but I am certain that this is either Migrant or Southern Hawker, and from what I can see I would probably go for Migrant Hawker (Aeshna mixta).
An idea of the size would be useful - this larvae is nearly fully grown (based on the size of the wing buds), and Southern Hawker larvae are usually considerably larger than those of Migrant Hawker when they reach their final instars.