Two Different Bluets

A fair amount of the time when I see similar-looking creatures in the same picture they turn out to be of the same species, but in this case we have a Familiar Bluet (top) and a Skimming Bluet (below). Frequently I'll use the presence of a distinctive male bird to identify a far less distinctive but nearby female bird. And the dark bird among the European Starlings is usually ... another starling!

But this isn't a perfect strategy. At a casual glance you might think these are the same species. You might even think that the extra blue on the top bluet is just natural variation. But there are times when these instincts lead you astray, and the odonate world is probably 1 of them. All damselflies and dragonflies lay eggs in water, so a good body of water frequently attracts multiple species, and at least some of them look similar.

In our defense, sometimes the odonates themselves get confused; some of them will chase of "rivals" that don't really compete against them but just have a superficial resemblance. (I'm looking at you, Blue Dasher.)

June 29, 2023 at Sourland Mountain Preserve
Photo 301249627, (c) jpviolette, some rights reserved (CC BY-NC)


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