Odonata
Es flattert um die Quelle
Die wechselnde Libelle,
Mich freut sie lange schon;
Bald dunkel und bald helle,
Wie der Chamäleon,
Bald rot, bald blau,
Bald blau, bald grün;
O daß ich in der Nähe
Doch ihre Farben sähe!
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Sie schwirrt und schwebet, rastet nie!
Doch still, sie setzt sich an die Weiden.
Da hab ich sie! Da hab ich sie!
Und nun betracht ich sie genau
Und seh ein traurig dunkles Blau -
 
So geht es dir, Zergliedrer deiner Freuden!
*

(Johann Wolfgang von Goethe)
* An English translation of this poem can be found here.
A case of double Dutch

Together, dragonflies and damselflies make up the order Odonata. Unlike English, Dutch has a common name for it:
libellen. Any member of this order is called a libel. When someone posts a picture of a libelle (note the le at the end) on a Dutch photography forum, there will always be a smart aleck remarking that Libelle is a women's magazine. True enough. Today, both the Flemish and Dutch editions of this weekly are owned by Sanoma, the Finnish group that, to my taste, has far too many fingers in the media pie of the Low Countries. Like most members of the male sex, I mainly associate Libelle with hairdressers, dental practice waiting rooms and features with the relevance of a horoscope and the news value of a pole-squatting record attempt, prompted by sly advertisers. A ridiculous prejudice, of course. Nevertheless, I am happy to say my wife reads neither Libelle nor any other similar women's magazine. In return, I do not purchase nude mags or periodicals about cars, motorcycles, soccer, model railways, DIY, video games and other so-called typically male interests that I find just about as compelling as the outpourings of some ephemeral media phenomenon or Pippa's behind. It will come as a surprise to many Dutch speaking nitpickers and language purists, but according to the Groene boekje and Van Dale* both a libel and a libelle are insects belonging to the order Odonata. Both spellings are correct. Moreover, while a libelle is
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Cover of the first Libelle (1934). The first article, De Prins der Dameskappers (The Prince of Ladies' Hairdressers) is about the Parisian society hair stylist Antoine, alleged inventor of the bob cut.

always a libel, a libel is sometimes not a libelle but a pamphlet or a kind of spirit level. Even though the spelling variant libelle already appears in the 1916 edition of the Woordenboek der Nederlandsche Taal (Dictionary of the Dutch Language), it is only officially approved in 2005. The fact that Dutch speaking odonatologists prefer the less unequivocal variant has nothing to do with their not wanting to be associated in any way with the popular women's magazine. They simply consistently use the official spelling from before 2005. Then, in all its wisdom, the Nederlandse Taalunie (Dutch Language Union) suddenly decides to grant the word libelle official status. Apparently, the variant is gaining ground, an evolution that is in all likelihood at least partly due to the fame of the brand name Libelle. Generally accepted historiography, however, dismisses any initial link between the title of the magazine and the common Dutch name for the order Odonata. A half-truth at best and, in my opinion, a whole lie.

* The Groene boekje (Green booklet) is the official list of Dutch words. Van Dale is the standard, most authoritative Dutch dictionary.


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In hoexkens ende boexkens

"In omnibus requiem quaesivi, sed non inveni, nisi in hoexkens ende boexkens."
(I have sought for peace everywhere, but I have not found it. Save in nooks and books.)

These days, in many cases more time and effort seems to be spent on coming up with a good name for a new magazine than on its actual content. I presume the original publisher of
Libelle gave it some thought too. Unlike today, however, the name was certainly not the result of a series of indecently expensive brainstorming sessions conducted by a team of communication and marketing experts. According to most sources, Libelle is simply derived from libellus, the Latin diminutive of liber or book. Other sources go somewhat further and claim that the name was invented by Jo or Johan Douwes, co-founder and first editor-in-chief of the magazine. He allegedly derived it from the Latin expression in angello cum libello or "in a nook with a book". According to many, this expression is based on the weird amalgam of Church Latin and Middle Dutch above. An early biographer attributes it to Thomas à Kempis, the 15th century author and mystic, who spent 60 of his 91 years in the Monastery of Mount St. Agnes in Zwolle (the Netherlands). Many different entirely Latin versions
of the quote circulate. One of them – In omnibus requiem quaesivi, et nusquam inveni nisi in angulo cum libro – concludes the preface of my English translation of Umberto Eco's masterpiece Il nome della rosa. Does the name of the magazine really have nothing to do with insects belonging to the order Odonata and everything with this quote from The Name of the Rose? Apparently, yes. But, as I am about to show, appearances can deceive.


Libelle and the beast

In 1934, the year the first
Libelle is published, the Dutch publisher Bosch & Keuning launches its so-called Libellen series. It concerns a series of mostly edifying booklets on the most diverse subjects. The relatively cheap publications find ready buyers and between 1934 and 1940 nearly four hundred issues appear. There is no doubt about the origin of the name of the
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The back cover of every issue features the logo and the slogan that both the name of the series and its logo are based on.

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Covers of the first (top) and fifth edition (bottom) of the first number of the Libellen series. Note the logo and its evolution.

series. The back cover of the very first issue, a booklet about American protestant missionary Eli Stanley Jones, already features the slogan Met een boekske in een hoekske (With a book in a nook). Later, it is supplemented with the Latin variant Cum libello in angello. But what really stands out is the logo of the series: a dragonfly, indeed. The somewhat awkwardly drawn but relatively true-to-life specimen of the first editions of the first numbers is soon replaced by a more stylized model with angular wings and ludicrously long antennae. From January 1935 to September 1937, Bosch & Keuning also publishes De libel – maandschrift voor deze tijd (The libel – monthly for
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René Lalique's dragonfly ladies are a testimony to craftsmanship but do not charm me at all. The specimen above misses a pair of wings and two pairs of legs. The head and boobs face the wrong direction. But it's mainly the symbolism that puts me off.

our times). The cover and the bottom of nearly every page feature the logo of the Libellen series. Even though the slogan of the series has nothing to do with Odonata, the sound of the Latin word libello obviously suffices to associate it with dragonflies. To me, it seems next to impossible that this obvious association completely escaped the founders of the women's magazine Libelle. What did the name of the weekly remind its predominantly female readers of? Taking into account the target group and the spirit of the age, it is far more likely that they associated it with dragonflies than with the diminutive of the Latin word for book. The fact that the name sounds French and that its second part is French for beauty or beautiful, was a bonus. Ça fait chic, non? Moreover, at the time the connotation with insects of the order Odonata was certainly welcome. Art Deco may have been on its last legs, but dragonflies were still a cherished theme of many interbellum decorative artists and artisans. They symbolized seductiveness, elegance, mystery, capriciousness, flamboyancy, impulsiveness, fragility and other good or bad qualities that even today mainly women are associated with. René Lalique, the celebrated French goldsmith and glass designer, laid it on with a trowel by giving some of his famous dragonflies a woman's head, breasts and claws. To my
taste, the result is a rather kitschy cross between a dainty fairy and a ferocious bird of prey. Conclusion? It is a long-standing myth that the name of the woman's magazine Libelle originally had nothing to do with dragonflies. Perhaps its founders, like those of the Libellen series, truly were inspired by Thomas à Kempis. But the logo of the series proves that the association with the insects was as obvious in 1934 as it is today and anything but unwished for. Dragonflies were hot.
Dragon or damsel?

According to the
Tree of Life Web Project, the order Odonata comprises some 6,500 species belonging to over 600 genera. In Belgium and the Netherlands, these days only some 60 species can be observed: about 40 dragonflies (suborder Anisoptera or uneven-winged) and around 20 damselflies (suborder Zygoptera or even-winged). Dragonflies are rather robustly built stunt flyers. Their large eyes are close together, often touching at the top of the head. At rest, they hold both pairs of wings spread practically horizontally or slightly pointing downwards. The base of their fore wings is narrower than that of their hind wings. Damselflies look more fragile and are far less agile flyers. Their slim abdomen resembles a straw and their spherical eyes are wide apart. At rest, they hold their wings,
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This four-spotted chaser illustrates the most striking characteristics of dragonflies.

which all have the exact same shape, folded above or along their abdomen. The proverbial exceptions that prove the rule are damselflies of the genera Lestes and Chalcolestes, commonly known as spreadwings. Their slender abdomen, two nearly identical pairs of wings and spherical eyes, however, preclude any confusion.
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At rest, like nearly all other species of damselflies, the blue-tailed damselfly holds its wings folded.



Help! A horse biter!


I have never met anyone that is scared of damselflies. Countless people, however, are terrified of dragonflies. They bite and/or sting, don't they? Actually, they don't. My daughter-in-law swears by all that is sacred that one day, as a child, she was viciously attacked by a giant dragonfly. The truly completely innocent creatures still scare the shit out of her. I do not doubt her story. In the garden, from time to time a hawker or blue emperor appears to be chasing me, perhaps because of the clothes I'm wearing. Many dragonflies are attracted to dark, shiny surfaces such as solar panels or even oil spills. Females of several species are often observed depositing their eggs on reflective float glass or gleaming coachwork. In Dutch, the migrant hawker (
Aeshna mixta) is officially called the paardenbijter or horse biter. In the Flemish vernacular of my home village, however, all species of dragonflies are called peirdebutters or horse biters. Horrifying, isn't it? All the children and the vast majority of grown-ups are afraid of them. At the age of ten, in a Science for Boys kind of book – girls in 1970 are
still supposed to be only interested in dolls, needlework and rope skipping – I read that dragonflies do not bite or sting and are perfectly harmless. I can hardly believe it but nevertheless decide to put it to the test. I catch a whopper of a dragonfly and take it out of my butterfly net by its wings, my fingers trembling with fear and anticipation. The beast wildly sways its abdomen back and forth, but its much-feared pincer-like claspers do not scare me. I now know they are simply the genital appendages of a male dragonfly. When I place the animal on the back of my other hand and let go of its wings, it calmly remains sitting still for a minute or so. Then it suddenly takes off and flashes out of sight between the spruces and broom shrubs that surround the pool. "Bet you a Coke that I dare to hold a horse biter in my bare hands!" My friends are convinced that I'm bluffing, but are happy to wager a five franc coin just to see me suffer unbearable pain. Suckers!


Of genera and species


"Restrain your all too great lust for knowledge, for there is much distraction and deception in it."
(Thomas a Kempis)

Knowledge is power. Power corrupts. Ergo: knowledge corrupts. The devious means by which I wheedled my friends out of a couple of old Belgian francs would certainly have confirmed Thomas à Kempis in his conviction that knowledge and science, rather than purifying and ennobling the soul, stain and debase it. The 15th century Augustinian prefers the simple peasant that doesn't know his arse from his elbow to the highly learned bookworm or conceited scholastic that "occupies himself with the study of genera and species". Not the genera and species of Odonata, mind you, but those of the winged inhabitants of the Heavenly Kingdom. Just like the mediaeval taxonomists of the Seven Heavens kept bickering over the number of species of angels and their hierarchical status, so modern taxonomists can't seem to agree on the classification of dragon- and damselflies. They distinguish different subspecies, species,
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Members of the genus Chalcolestes, such as this willow emerald damselfly, spread their wings at rest, almost like a dragonfly.

genera or even entire families and basically make a mess out of it. Hopefully, in coming years DNA research will help to put things right. Current taxonomies of Odonata are mainly based on external features of nymphs and adults. Tricky, for these characteristics are often deceiving. Chances are that none of the current taxonomies entirely reflects the true evolution and relationship of all scientifically described species. As always on this site I use the largely identical taxonomic trees of the official Belgian Species List and the Dutch Species Catalogue. Being an amateur, I cannot judge their quality or up-to-dateness, but that goes for all other taxonomies as well. Nevertheless, I regret the fact that, while both taxonomic trees distinguish the same nine families of Odonata native to the Low Countries, they do not differentiate between the suborders of dragonflies or Anisoptera and damselflies or Zygoptera. Why not? Beats me!
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Four specimens of the species Ischnura elegans (blue-tailed damselfly): A male (top) followed by three forms of the exceedingly variable females (forma violacea, forma rufescens and forma infuscans-obsoleta).



Pro forma


The same book that teaches the precocious and somewhat sly teen I used to be that dragonflies are perfectly harmless also describes and illustrates a simple method to preserve these stunning creatures. I can still visualize the colourful, beautifully drawn plates. The procedure involves ether, pins, a razor blade and a straw to replace the abdominal entrails. How exciting! I can't wait to have a go at it, but the disappointing results soon put a damper on my initial enthusiasm. Once preserved, in less than no time my carefully prepared jewels lose all their splendour.
Such, Joy-Dissector, is thy case indeed! Goethe, the eminent German author and naturalist, already knows it: One can dissect and analyse just about anything that gives one joy or pleasure to death. Nevertheless, I do not agree with the rather ingenuous moral lesson of the poem that introduces this section, obviously at least partly and perhaps even mainly aimed at Newton's theory of colour. It's just that I also draw pleasure, emotion, comfort and even pure delight from the knowledge that my fellow human beings gathered through the centuries and are still gathering by carefully observing, collecting, dissecting and searching for similarities, differences and conceivably meaningful patterns. Of course, our tendency to more or less create order in the chaos that surrounds us often leads us astray. Simply think of the utterly illusory principles of astrology or the wacky wrinkles of the doctrine of signatures. However, the same, evidently irrepressible urge is also at the base of what we now call 'science'. In spite of his criticism of Newton's analytical approach to light or the ardour with which his contemporaries collect, preserve and dissect plants and animals, Goethe himself is just about as proficient with the scalpel as he is with the pen. At the age of 35 he discovers a bone in the human upper jaw previously known only in other animals – the os intermaxillare – and in 1796 he launches the term 'morphology' or the study of the shape and structure of
external and internal parts. Until well into the 20th century, morphological and anatomical similarities and/or differences are by far the most important criteria for the classification of life. Morphology and anatomy show that whales are not fish but mammals. Today, molecular biology allows us to refine and rectify the old classifications.
DNA research shows that hippos are more closely related to whales than to any other living mammals, including all other pachyderms. As yet, however, most taxonomic trees are still entirely or largely based on morphological and anatomical data. This is certainly the case for the order of dragon- and damselflies. Some indigenous species can be identified at a single glance, even in the field. Others require a trained eye. A few resemble each other so well even razor-sharp photographs do not always allow telling them apart. The darters or meadowhawks to the right resemble each other like two drops of water, but actually represent three different species. It's all in the details. To a layman, the specimens in the photographs above probably look like four different species of damselflies. Yet they all belong to the same species. Female blue-tailed damselflies are so variable that odonatologists distinguish several colour forms, each of which has an impressive sounding Latin name. Ridiculous? Not to my eyes. Variation is not merely a source of wonder; it is at the basis of the overwhelming biodiversity of our planet. I'm not cut out for it myself, but I do appreciate and admire the unremitting zeal with which taxonomists hammer away at systematically naming, describing and classifying life on Earth. To do this, they inevitably have to catch, kill, preserve or dissect some specimens. Meanwhile, I am extremely annoyed by government agencies and other institutions making a great song and dance about the conservation of biodiversity, but doing little or nothing to promote and finance the study of that celebrated diversity. Unlike what even most educated people believe, the vast majority of our planet's species has yet to be discovered and/or scientifically described. Taxonomy is neither sexy nor profitable. Of course, the fact that many field biologists somewhat pityingly regard their taxonomic colleagues, commonly attached to natural history museums, as the philatelists or bookkeepers of their science, isn't helping either. Their hero is 22-year-old Charles Darwin, circumnavigating the world on board the Beagle, elated by the mind-boggling diversity of life on different continents and islands. My hero is the even younger Darwin, collecting beetles, or the somewhat older Darwin painstakingly
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From top to bottom: male of the ruddy, the common and the moustached darter. These photographs do not allow identification to species level.

studying, preserving, dissecting and systematically describing barnacles for eight long years. Both heroes could have conceived and developed the theory of evolution by natural selection. But it is the combination of both in one and the same person, the field biologist and the taxonomist, that turned Darwin into modern-day biology's superhero.
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In profile the secondary sex organ of male Odonata (top) is clearly visible. It is absent in females (bottom).

Male or female?

There's no doubt about the identity of the damselflies to the left. They are two adult azure damselflies, one of the most common Odonata in the Low Countries. The species owes its name to the little variable, usually mainly blue males. Females are far less uniform and often harder to identify. Specimens of both sexes can easily be mistaken for male or female variable damselflies. But not in the garden at 37 Heuvelstraat, where the variable damselfly, also known as the variable bluet, is absent. In other parts of Flanders and Belgium the species is rare, extremely rare or endangered.


Male: secondary sex organ

Males of all dragon- and damselflies are equipped with a secondary sex organ that is usually clearly visible. It is located right behind the thorax, on the underside of the second segment of the abdomen. This peculiar organ, which no other insects possess, is used for storing and transferring a sperm package, produced by the primary sex organ at the tip of the abdomen. It explains the typical mating wheel or
copula of Odonata. An endearing scene? Photographs of the more or less heart shaped mating wheels can usually count on being applauded and admired. But how are these magnificent mating wheels formed and what exactly is going on? I'm afraid the
answer is fairly disenchanting and leaves little room for romantic interpretations. In full flight, using the grasping cerci or claspers at the tip of his abdomen, the male firmly grasps the female by the head or the pronotum, a plate-
like part of the thorax. The result is a so-called tandem formation. The mating wheel is formed when the female bends her abdomen, reaching for the male's secondary sex organ to retrieve a sperm package previously stored there. The claspers of males of a specific species of damselfly exactly fit the pronotum of females of the same species. Those of male dragonflies can only grasp the back of the head of females of the same species. Every Jack has his Jill, so for all intents and purposes interspecific mating is next to impossible. Nevertheless, in the field every now and then tandems and mating wheels of two different species of dragon- or
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damselflies are observed. This usually concerns very closely related species, such as the common and Siberian winter damsel, but copula of Odonata belonging to different genera have also been observed and documented.
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Using the tip of her abdomen, the female transfers sperm from the secondary sex organ of the male to her own reproductive organ (top). Meanwhile, using the tailor-made claspers on the tip of his abdomen, the male keeps her firmly in check (bottom).

Apparently, some Jacks have more than one Jill. To the best of my knowledge, it is unknown if interspecific matings can sometimes produce fertile or even only viable hybrids. It wouldn't come as a surprise to me, however, especially not concerning species that are barely distinguishable and should, if it turns out that they can and do still exchange genes, be considered as subspecies rather than true, separate species.


Jealous guy


When the sperm package has been transferred, the wheel position is broken and the female deposits her now fertilized eggs. In many species, such as the azure damselfly, the male does not release the female and the couple flies hither and thither in tandem. There's a good reason for this, at least from the male's point of view. His secondary sex organ is equipped with a brush-like scoop that allows him to remove the sperm of a predecessor from the female genitalia. Good riddance to bad rubbish. By releasing his partner only after she has deposited her eggs, he prevents rivals from doing the same with his own precious sperm. Males of other species usually stick around to chase away any rivals that approach a female they have fertilized. An exhausting preoccupation, occasionally ending in disaster.


Choosy lady

Most animals are not into romance. They don't have time for that. As a rule, adult dragon- and damselflies only last a couple of weeks. They have better things to do than wasting time and energy on elaborate courtship. Their heart shaped mating wheels may melt even the most frigid iceberg, but to a dispassionate observer they initially look more like brutal rape than an amorous embrace. Nevertheless, female Odonata are far from utterly defenceless victims of the male sex drive. Not only are they perfectly capable of breaking up a tandem or copula, they can even deliberately withhold
some of the sperm of previous suitors. Sexual selection by choosy females is common in nature and, at least to some degree, Odonata are no exception.


Female: ovipositor or vulvar scale


Whether or not in tandem, all damselflies deposit their eggs in plants, usually just above or below the water surface. They do this using the ovipositor at the tip of their abdomen. Females of some dragon fly species have a similar apparatus. They drill their eggs into plants, like the blue emperor below, or into the bottom. Other species of dragonfly simply scatter their eggs above the water or deposit them just below the surface or on muddy banks. For a fraction of a second, usually in tandem, the female dips the tip of her abdomen in the water or the mud. Females of these species do not have an ovipositor but a vulvar scale. It is clearly visible in the photograph of the common darter to the right. The shape and visibility of this thorn-like appendage differ from species to species. Female Odonata produce a few hundred to thousands of tiny round, oval or elongated eggs that will hatch in a couple of weeks or months. It all depends on the circumstances, such as the temperature and quality of the water. Just a couple of days after reproduction, in many ways a bruising battle, most damselflies kick the bucket. Dragonflies sometimes last a few weeks longer, but visibly deteriorate. Their mission is accomplished.
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Copula of the common darter on the patio bordering the garden pond (top). The female's vulvar scale is clearly visible (bottom). Its shape helps to identify this species.

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Nymph of a darter. Dragonfly nymphs have internal rectal gills. They breathe by pumping water in and out of their abdomen. By doing this quickly, they can propel themselves forward with surprising speed.

Larva or nymph?

Dragon- and damselflies are hemimetabolous insects, just like true bugs and grasshoppers. Unlike flies, butterflies, beetles, bees and other holometabolous insects, they have no pupal stage. Juvenile dragon- and damselflies do not undergo a complete metamorphosis, but a series of incomplete metamorphoses. After each such metamorphosis or moult they look a bit more like an adult individual or imago. Just before the final, in every respect most spectacular metamorphosis, they leave the water, usually by climbing up the stem of an aquatic or littoral plant. In most books and on most websites on Odonata they are called larvae. Nothing wrong with that, but I prefer to reserve the term 'larva' for juvenile, not yet pupated holometabolous insects. Juveniles of hemimetabolous insects that have to go through at least one more partial metamorphosis, I consistently call 'nymphs'. From the egg of a dragon- or damselfly, after a few weeks or months a worm-like creature or pronymph emerges. This is actually the last embryonic stage. DNA research shows that holometabolous insects evolved from hemimetabolous insects. It may well be that their
larval stage is in fact a hormone induced prolongation of the pronymph stage of a hemimetabolous ancestor. In that case, pupation could be looked upon as a succession of several nymphal stages compressed into a single
complete metamorphosis. Pronymphs of dragon- and damselflies that deposit their eggs above the surface or on the banks, wriggle their way into the water. After the first moult, depending on the species usually within just a few seconds or minutes, the animal is a true nymph that autonomously moves, hunts and feeds.


Masked murderer

Nearly all dragon- and damselflies spend by far the largest part of their lives as nymphs in the water. Europe has just two exceptions: the common winter damsel and the Siberian winter damsel, also the only European species that hibernate as adults. Their nymphs emerge after less than three months, while the adult winter damsels can last for up to ten
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Nymph of a damselfly. All damselfly nymphs have three tracheal gills or caudal lamellae at the end of the abdomen. They are used for respiration and propulsion.

months. Most nymphs of dragon- and damselflies, however, spend almost one or two years in the water and some species take nearly five years to grow to maturity. They moult nine to seventeen times and are formidable predators. Just about anything that moves and isn't too big is on the menu: bloodworms and other insect larvae,
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Exuvia of a blue emperor. Part of the catching mask or mentum is clearly visible.

small fish, tadpoles, even other dragon- or damselfly nymphs, including individuals of the same species. Reportedly, when depositing eggs beneath the surface, even adult dragon- and damselflies are not safe from these ferocious hunters. The lower lip of all Odonata nymphs develops into a somewhat bizarre, flattened and distinctive structure: the extendable mentum or catching mask. As soon as something that looks like a meal ventures too close, the mask shoots out with lightning speed and movable hooks or teeth at the end of it firmly grasp the
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Nymph of a darter. Part of the catching mask, the prementum, covers a large part of the face.

unsuspecting creature. The mask retracts and the prey is gobbled up immediately. Sounds cruel, but of course most nymphs will themselves end up in the digestive system of a water beetle, a fish, an amphibian, an aquatic bird or another dragon- or damselfly nymph. Small wonder they generally lead secluded lives, well hidden between aquatic plants or in the bottom mud. In the field, you rarely get to see one, not even in limpid water. And then it still has to go through the most hazardous stage of its life.
Emergent!

For the final metamorphosis or emergence, the fully-grown nymph leaves the water. Describing what exactly happens next is best left to the experts. The photos to the right illustrate the emergence of a blue hawker and speak volumes. Most dragon- and damselflies emerge at the crack of dawn or even at night. Better be an early bird if you want to observe and admire the entire extravaganza. Make sure you have time to spare too, because it can take a while. It all depends on the species involved and prevailing conditions such as the weather, temperature and humidity. The photographs are taken on the morning of 3 July 2011. The first one at a quarter past eight; the last one nearly three hours later.


Risky business

While emerging, dragon- and damselflies are extremely vulnerable and wholly defenceless. Many birds seize the opportunity to get a piece of the pie. But frogs, ants and even foxes are not averse to fresh Odonata meat either. In the garden at 37 Heuvelstraat, Moke, one of our adopted shelter cats, has become an expert in plucking newly emerged dragon- and damselflies from the air on their somewhat faltering maiden flight. When he catches a damselfly, he eats it whole and without further ado. But when he catches a dragonfly, he always brings it indoors, proud as a peacock with a bloated ego. The poor creature is usually badly bruised and beyond saving. Fortunately, most newly emerged dragon- and damselflies are already on the wing before Moke sets out on his morning patrol. But even emergers that do not fall prey to hungry birds, frogs or insectivorous cats do not always make it, not by a long shot. Fully-grown nymphs appear to be capable of postponing emergence until conditions are pretty much ideal. Nevertheless, an unexpected summer downpour, especially when accompanied by strong gusts of wind and hail, can always throw a spanner in the
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Emergence of a male blue hawker. The imago does not yet have its final colouration. In entomology jargon, such newly emerged imagos are called tenerals.

works. In any case, the final metamorphosis is so drastic that even in the best of circumstances things can and do still often go wrong. Many dragon- and damselflies simply don't manage to struggle out of their nymphal skin. Others succeed, but end up with one or more deformed wings or a severely distorted abdomen. All of them are
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Teneral of a blue hawker after an unsuccessful emergence. Both its wings and abdomen are deformed.

doomed. The ratio between the number of successful and that of failed emergences varies from year to year and from place to place, indicating that weather conditions are probably decisive. In any case: Observing the emergence of a dragon- or damselfly for hours on end until it finally flies off with wings that are still shiny, is one of my favourite pastimes and I wouldn't miss it for the world. Cheetahs chasing impalas? Giant pandas sledging down snowy slopes? Emperor penguins crossing the ice in Indian file to reach their breeding colony? Three-toed sloths in the canopy of the Amazon rainforest doing their utmost to make the koala bears in the Australian eucalypt forests look like energetic fidgets? Marvellous, I'm sure, but I'm quite happy reading about it or watching it on TV. Meanwhile, day in day out, the wildlife in the garden provides all the spectacle and excitement I need and keeps amazing me. I just can't get enough of it. A herd of wildebeests or a parade of elephants crossing the African savannah? Pretty impressive, no doubt, but I still prefer observing the antics of the creepy crawlies that inhabit the garden and never fail to entertain me. Admittedly, the fact that I hate travelling and would rather be a live dog than a dead lion comes into it too. When all's said and done, I have the sense of adventure of an English oak.


And the winner is…

Except for the willow emerald damselfly, all species of dragon- and damselflies I've observed in the garden to date also reproduce in it. They are attracted by the garden pond where they deposit their eggs. From time to time, I also get to see a nymph, especially while cleaning the pond. Of most species, I've already observed at least one emergence. And then there are the exuviae, the conspicuous telltale nymphal skins emergers leave behind. Each year, I discover dozens of them, usually on aquatic or littoral plants. Now and again, I find one hanging on a window frame, a facing brick or the leg of a patio chair. To reach those, the nymph has to cover a distance of at least a few metres. The record is currently held by the black-tailed skimmer to the right. The nymph climbed out of the pond, crawled at least 3.6 metres across the rough tiles of the covered patio, climbed 2.7 metres up the outer brick wall of the house and finally covered yet another 20 or so centimetres on the wooden ceiling, upside down. A top-notch performance! The photo dates from July 2011. While I'm observing and capturing the emergence, standing on a stepladder, the sky clouds over and a heavy thunderstorm with lashing rain and huge hailstones breaks out. Out in the open air no emerger could have survived such a deluge! So was this record-breaking champion simply lucky? Or did the creature somehow know that it had to find a well-sheltered place? It seems unlikely, but the number of exuviae that I find on the patio clearly increases when weather conditions are unstable. Can fully-grown nymphs predict the weather? Are they
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To reach the ceiling of the patio, the nymph of this black-tailed skimmer had to cover over 6.3 meters on dry land. The imago emerged during a heavy thunderstorm.

equipped with some sort of internal barometer? I don't know, but it's certainly not impossible.
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Newly emerged large red damselfly with exuvia. Captured on 9 April 2011.



Total make-over


Most dragon- and damselflies emerge in late spring or summer. Fully-grown nymphs of some species, however, leave the water much earlier. In the garden, spring is not announced by the return of barn swallows from Africa but by the emergence of large red damselflies from the pond. In early April 2011, I observe and capture the emergence of the large red damselfly to the left. The similarities between the legs and head of the exuvia and those of the imago with its beautiful eyes that do not yet have their final colouration are striking. But the resemblance stops there. Even though the emergence is simply the final partial metamorphosis, the transformation is so extravagant that it reminds one of the emergence of a butterfly, a beetle or another
holometabolous insect. It takes a lot of imagination to recognise the imago of a blue hawker in the exuvia below. But how else could it be? After all, the creature not only changes shape, it also switches habitats. In one go, an organism that is perfectly adapted to life in the water turns into a flying terrestrial animal. It's as if a fish would suddenly change into a bird or a submarine into an aeroplane. Fascinating, isn't it?
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The shiny wings of this newly emerged blue emperor are not yet fully transparent.

Thirteen to the dozen

In June 2006, barely a year after the construction of the garden pond, the first dragonfly emerges at 37 Heuvelstraat. It's a blue emperor. At the time, I've not yet started documenting the garden's biodiversity, which explains why I don't have any photographs of this premiere. Too bad. Fortunately, both adults and nymphs of the species are still present in the garden and the pond. The photo to the left dates from 2011. I rescue the newly emerged creature from the claws of our cat, put it on my wife's forefinger and quickly take some photographs. Another species that turns up from the start is the small bluetail or scarce blue-tailed damselfly. Ever since the regional extinction of the pygmy damselfly, this is the smallest damselfly in the Low Countries. Of the five damselflies and eight dragonflies I've
already observed in the garden, this is the only species I have hardly any photographs of. That's because it disappeared. Alarming? Not at all. In fact, it's the normal course of events. The small bluetail is a pioneer with a distinct preference for new ponds, puddles and pools with lots of open water and little or no vegetation.
Presumably, the species can't compete with other, larger damselflies, so it always has to colonize new, unoccupied breeding territories. My only and perhaps last photographs of small bluetails are all made in July 2010, the very first year I set myself to document and identify the dragon- and damselflies in the garden. It is very well possible that, today, from time to time a small bluetail looking for a breeding pond turns up in the garden. But the odds of me spotting such a rare vagrant are exceedingly small. It would not stand out, certainly not among the numerous azure and blue-tailed damselflies that dominate the verdant pond today. Whatever the case, of the thirteen species in the current
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Female tenerals of the small bluetail are almost completely orange, which excludes confusion with any other native species.

species gallery, twelve still frequent the garden on a regular basis or spend their entire life in it. Not bad at all, since they represent over 20 percent of all Flemish dragon- and damselflies.
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Adult Odonata do not have a catching mask, but they do have sharp jaws or mandibles. Damselflies use them to catch and eat prey. Dragonflies scoop up prey with their legs and eat it in full flight.



Please, sir, I want some more…


Prior to 1990, Flanders counted 64 species of locally reproducing dragon- and damselflies. By now, six of them are regionally extinct, while according to the 2005 Red List seventeen species are either critically endangered (3), endangered (7) or vulnerable (7). Currently, thirty-two species, including all dragon- and damselflies in the garden, are not threatened. This does not mean they can be found just about everywhere. Many dragon- and damselflies have very specific habitat requirements. Some species will only breed in flowing water, for instance, while other species require brooks or pools that regularly dry out and have few or no predators. Bottom soil characteristics and the quality and acidity of the water matter too. Out of the 58 species of indigenous dragon- and damselflies left in Flanders, 17 have never been observed in my part of the region. Thirteen species that do occur here require living conditions the garden simply doesn't offer, such as a fast-running stream or a slow-running brook. Some ten species may one
day turn up in the garden, but won't stick around for lack of suitable breeding conditions. In the end, only twenty species really qualify, thirteen of which have already shown up while twelve are still present. The seven other potential guests are the brown hawker, the migrant hawker, the dainty bluet, the common spreadwing, the common
winter damsel and both the large and small redeye. They are, of course, more than welcome.


Source of joy


At the back of the garden, in between the kitchen garden and the orchard, there is still a relatively large lawn. In coming years, I plan to upgrade this green desert step by step into a colourful oasis bursting with wildlife. If circumstances and, in particular, finances permit, I'd love to include a large, perfectly natural amphibian pond without pond liner or artificial filter system. In that case no doubt, for a couple of years, the small bluetail would once again feel at home. Chances are such a pond would also attract at least a few of the as yet never observed potential guests. But that's all in the future. Right now, I'm as pleased as Punch with the pond next to the patio and the dozen species of dragon- and damselflies that reproduce in it. The joy these flying jewels bring me year in year out is simply priceless. From early April to late autumn they brighten my days and somehow manage to relieve my mind. They always cheer
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Portrait of a clearly senescent moustached darter. Captured on 18 October. In the garden, this species can often be observed till late November.

me up. Knowing they have only a couple of weeks left to live and are basically the way their nymphs reproduce doesn't detract from that at all. Quite the contrary! Thomas à Kempis and Goethe are wide of the mark. My great lust for knowledge and my analytical mind do not distract me and are anything but a source of deception or sorrow. The glorification of ignorance is truly lost on me and my well-nigh instinctive aversion to it is increasing year by year. It gives me, whether or not in angello cum libello, the heebie-jeebies.
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Sources and links to more information

  • Basisrapport Rode Lijst Libellen, De Vlinderstichting, 2011 (PDF).
  • Brachytron: site of the Dutch Society for Odonata Studies.
  • Geert De Knijf, De Rode Lijst van de libellen in Vlaanderen, Instituut voor Natuur- en Bosonderzoek, 2006 (PDF).
  • De Nederlandse Libellen: wonderfully illustrated identification site by Goyatlah.
  • Klaas-Douwe B Dijkstra, Libellen van Europa – Veldgids met alle libellen tussen Noordpool en Sahara, Tirion Natuur, 2008.
  • Umberto Eco, The Name of the Rose, Picador, 1984.
  • Johann Wolfgang von Goethe, Schriften – Vierter Band, Georg Joachim Göschen, 1787.
  • Stephen Jay Gould, Eight Little Piggies – Reflections in natural history, Penguin Books, 1994.
  • Joop Groenendijk en Rens Strijbos, Libellen-serie 1934-1940 – uitgegeven door Bosch & Keuning te Baarn – Catalogus van de volledige collectie van Joop Groenendijk te Eerbeek, 2002 (PDF).
Geraardsbergen, 13 July 2014.
Latest revision: 30 October 2017.