Common Baskettail dragonfly (male)

Common Baskettail dragonfly (male)

The preceding baskettail dragonfly was spotted perching in the grass along the earthen dam at Hidden Pond, a small lake located at Meadowood Recreation Area in Fairfax County, Virginia USA.

Baskettail dragonflies perch rarely. This one flew around me  in wide circles for 15-20 minutes before it landed just long enough for me to shoot two photos, one of which suffers from soft focus.

[Several species of baskettail dragonflies] have proven to be very difficult to identify, particularly from photographs. Most species are quite variable and there is evidence that they may hybridize and/or integrade, making identifications even tougher. … The single most important character [field marker] potentially visible on a photograph is the shape of the abdomen. For this reason it is very important to photograph individuals dorsally. Source Credit: Identification of Male Epitheca (Tetragoneuria) in Texas, by John Abbott.

Fortunately my photograph shows a good view of the dorsal side of the dragonfly. I tentatively identified the specimen as either a Common Baskettail dragonfly (Epitheca cynosura) or Slender Baskettail dragonfly (Epitheca costalis), probably male. I consulted the experts of the Northeast Odonata Facebook group for verification. According to Ed Lam, author and illustrator of Damselflies of the Northeast, this individual is more likely a Common Baskettail and definitely a male. Thanks for your help, Ed, including the pointer to John Abbott’s excellent article!

I think the width of the abdomen fits Common better than Slender. S4-6 look about as wide as they are long. S4-6 are longer than they are wide in Slender. Also the tips of the cerci are flared outward [in Common] while they are usually more parallel in Slender. Source Credit: Ed Lam, Northeast Odonata Facebook group.

Remember that “S4-6” refers to abdominal segments four through six (of 10), numbered from front to back.

Copyright © 2014 Walter Sanford. All rights reserved.

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