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As Matt Smith says, you need to look at the mandibles (double toothed at tip) to definitely distinguish ruficornis from related 'tricoloured' species (yellow, red & black on abdomen and red markings on thorax). This is easily doable in the field. This example is actually more likely to be N flava, the commonest member of the group, which tends to have much stronger yellow abdominal markings than ruficornis.
Thanks Ian, this is a new group to me and all noted. Chris.
Chris Brooks - www.dragonfly-images.co.uk
My Flickr site - www.flickr.com/photos/ceb1298
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