Blue Dasher Dragonfly – Pachydiplax longipennis

Blue Dasher Male

Blue dashers rarely sit in one spot for long. The males are constantly patrolling their territory, dashing out from their perch to challenge other dragonflies or large insects flying nearby, and looking for females with which to mate.

Dragonflies are completely harmless – they do not sting or bite. Indeed, they are beneficial in the same respect spiders and other predators are beneficial – they keep the burgeoning insect population in check. Many of these species prey on each other; I often see dragonflies with damsels in their clutches.

Blue Dasher Female

Dragonflies are among the most ancient of living creatures. Fossil records, clearly recognizable as the ancestors of our present day odonates, go back to Carboniferous times which means that the insects were flying more than 300 million years ago, predating dinosaurs by over 100 million years and birds by some 150 million.

Those Famous Eyes

Dragonflies have excellent eyesight. Their compound eyes have up to 30,000 facets, each of which is a separate light-sensing organ or ommatidium, arranged to give nearly a 360° field of vision, important for taking prey on the wing, as has done the male above and female below.

Female blue dasher

Much larger dragonfly species existed in the distant past than occur on earth today. The largest, found as a fossil, is an extinct Protodonata named Meganeura monyi from the Permian period, with a wingspan of 70-75 cm (27.5-29.5 in). This compares to 19 cm (7.5 in) for the largest modern species of odonates, the Hawaiian endemic dragonfly, Anax strenuus. The smallest modern species recorded is Nannophya pygmaea from east Asia with a wingspan of only 20 mm, or about ¾ of an inch.

Dragonflies are the world’s fastest insects and, although estimates of their speed vary wildly, most credible authorities say they are capable of reaching speeds of between 30 and 60 km/h (19 to 38 mph). A study showed that dragonflies can travel as much as 85 miles in one day.

Insects | Dragonflies | Damselflies | Bugs Index | Spiders