The frustrating Iberian Bluetail; frustrating because it exists alongside the Common Bluetail (Ischnura elegans) in the Iberian peninsular and can be terribly difficult to separate.
The most reliable distinguishing feature is the trailing edge of the pronotum, as is so often the case in damselfles. The males, particularly, of I. elegans show a central spine which is absent in I. graellsii. Since it is a fine feature often being being black on black and surrounded by hairs, clear photos at the appropriate angle are required. If you are really lucky, you’ll find an I. graellsii with dramtically curtailed or missing antehumerals and/or much reduced or missing post-ocular spots. Range helps – I. graellsii generally being a more westerly species.
I would like these pictures to be clearer but, based on enlarged images, I think they are correct.
| male | ||
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| female |
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| in cop |
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