Dragonflies and damselflies (Order Odonata) are among my favorite insects, perhaps after ants, bees and wasps. They are beautiful, especially when alive (even with acetone treatment, the colors are never as vibrant in dead specimens as in the live insects.) They are among the best fliers of the insects and have among the best eyesight of any invertebrate (cephalopods and jumping spiders eyes may be better.)
They are also very ancient, with fossilized specimens from the Jurassic being nearly indistinguishable from some modern forms. Their relatives were flying in the Carboniferous forests and so they have survived several major extinction events, although the scorpions beat them out for the land arthropod survival record, having existed since the Silurian and had emerged onto dry land by the Devonian.
I was first enchanted with dragonflies by reading an article in the National Geographic by James G. Needham (August, 1951.) Little did I know then that I would eventually know the co-author, Minter Westfall, of the second edition of Needham’s Manual of the Dragonflies of North America, published in 1955 and followed by a completely revised version in 2000, after the death of Dr. Needham, with an additional co-author Michael L. May. Professor Westfall was an interesting man and I got to know him fairly well while I was at the University of Florida. Among other things I got to see his collection of odonates, kept in glassine envelopes instead of the usual insect pins, and treated with acetone to preserve as much of the original colors as possible.
While in New Mexico I taught courses in aquatic insects and thus added to my knowledge of both dragonflies and the frailer damselflies. I started to take photographs of them when I got the opportunity and thus added several species to the known fauna of the area. Some dragonflies are very difficult to photograph, especially the large darners, and it takes a lot of persistence to get good images. Still it is very much worth it!
The Odonata are divided into three suborders, of which two occur in the United States and Canada. Our suborders are the Zygoptera (damselflies) and the Anisoptera (dragonflies). The most common families of the Zygoptera are the Calyopterigidae (broad-winged damselflies or demoiselles), Lestidae (the spreadwings) and Coenagrionidae (or pond damselflies.) The most common families of the Anisoptera are the Aeshnidae (the darners- the largest in body size members of the order), Gomphidae (the club-tails) and the Libellulidae (Skimmers, Meadowhawks, Pondhawks, etc.) The Libellulidae contains the largest number of species in North America.
The odonates, while as adults definitely terrestrial, and some almost always in the air, start out as strange aquatic nymphs (often called naiads- which I prefer as it tells you that they are aquatic, and these days the convention is to refer to them as larvae). These creatures look very different from the adults and have extensible lower lips (labia) with hooked claws. They use these to capture prey, for they, and the airborne adults, are aggressive predators. In the case of the naiads, of small fish, tadpoles, other aquatic insects and even other dragonfly or damselfly naiads. The naiads of damselfly species are easily distinguished from those of dragonflies because they have external gills as projections from their abdomen. Dragonfly naiads have internal gills. Odonate immatures can exist in very small puddles and some even can be terrestrial in rain forests, where they remain wet during their early stages.
DRAGONFLY AT REST
Adult dragonflies are especially familiar and their aerial acrobatics, beautiful colors and delicate wing structure have inspired poets and artists for hundreds, if not thousands, of years. They are, of course, important in their own function as predators of other insects, including mosquitoes. Although most odonates breed in water, the adults of dragonflies are strong flyers and can be found many miles from a lake, marsh or pond. Males often stake out territory from which they drive other males. Females coming into this territory are seized and mating takes place. The males of some odonates then clasp the female back of the head and provide a flying platform as they lay their eggs. In other species the female lays alone and may even mistake a shiny car surface for water and attempt to lay eggs there.
There are many references on odonates, and in recent times binocular identification has become popular, so several books treat the identification of them using these, such as Sydney Dunkle’s Dragonflies Through Binoculars (2000). There are also several definitive books on odonate identification. Among these are Dennis Paulson’s Dragonflies and Damselflies of the East (2012) and Dragonflies and Damselflies of the West (2009). A more specialized book is Tim Manolis’ Dragonflies and Damselflies of California. However it has excellent illustrations and most of the West Coast species are included.
[This article on Dragonflies first appeared in Backyard Science, SciTech, and Community Spotlight. All of the pictures used are by the author. We are publishing the story with the permission of Daily Koz. We found it both informative and interesting and believe our readers will, too.]