Blue Dasher

After yesterday interrupted my dragonfly posts, let's resume with this Blue Dasher picture. This was the 3rd species of blue dragonfly that I saw on this trip, after the Eastern Pondhawks and Slaty Skimmers. Though I saw only one of these guys compared to around 7 EPs and 2 Slaties, Blue Dashers are far from rare around here.

At a glance, I can usually distinguish them from the male EPs because of the black tip at the end of their abdomen. Though both species develop a similar light blue pruinose, the pruinose starts forming at the end of the EP abdomen, so even if the was an immature EP, the non-pruinose part of the abdomen would be in the wrong place. And the pruinose color is also a little different; while the EPs usually look baby blue, the Blue Dasher has more of a bluish-white look. The Blue Dasher's jade eyes and white face also differentiate it from the EPs. 

The Slaties are even easier to differentiate from the Blue Dasher, with a much darker blue pruinose and their dark eyes/face. I could only imagine thinking a Blue Dasher is a Slaty Skimmer if you saw one in dim light.

These are probably the Big 3 of my area's blue dragonflies. We'll also see some (difficult to ID) bluets around here, but they're the slenderer damselflies, and are unlikely to be confused with the dragonflies.

July 23, 2021 at the Plainsboro Preserve
Photo 148594203, (c) jpviolette, some rights reserved (CC BY-NC)


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