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SINGAPORE In Gynacantha, it is probable that the increased size and efficiency of the eyes make possible the swift and often erratic flight. Nevertheless, it is likely that Gynacantha escapes the ever present danger of spider webs not by keenness of sight but by sheer bulk and momen- tum. It is common to find a fully adult Gynacantha with bits of spider webs attached to its wings or body, strands which would have proved the undoing of other smaller dragonflies. Crepuscular flight is probably an adaptation to the food supply, as there is a big burst of small insects fly- ing everywhere at dusk. It could also be that there is reduced predation from birds during the crepuscular hours. The Gynacantha species typically cease to fly as soon as the bats begin. The common aeshnid Lesser Green Emperor (Anax guttatus) inserting eggs into sub- It is very difficult to observe these merged reed. Photo: Francis Alvin Lok. wildly darting forms when they are in full flight. It is far easier to observe them Giant Hawker (Tetracanthagyna plagiata) female, in characteristic aeshnine position with down-hanging abdomen. Photo: Tay Soon Lian. by flushing them from their diurnal roost. When flushed, they usually fly a short distance and alight on some twig or stem, or in the undergrowth, in char- acteristic aeshnine position with down- hanging abdomen. Ode to Odonata Curious about their specific Text by Cheong Loong Fah, Tang Hung Bun and Robin Ngiam Wen Jiang identification, we have actually caught them by hand. Examining their wings and appendages under a field magnify- With a new book out soon about dragonflies Nowadays, T. plagiata vies with a couple ing glass, we have been rewarded with of other giants for the honor of being the discovery of aeshnid species new and damselflies (order Odonata), odonating recognized as the world’s largest known to Singapore, like Gynacantha dohrni, (i.e. watching dragonflies) is about to take off living dragonfly. Heliaeschna crassa, and Heliaeschna unin- ervulata. in Singapore in a big way. Here we provide Hawkers (Aeshnidae) T. plagiata, like many other members Dragons Of The Air an introduction to help beginners find their of the Aeshnidae family, exhibits a cre- (Gomphidae) puscular lifestyle. However, the evening No spectacle of the odonate world is way amongst a conspicuous and fascinating A Dingy Duskhawker (Gynacantha subinterrupta) female with its large eyes. Strands of spi- hours in our forests really belong to more awesome than the flight of the der webs can be seen attached to the wings and bodies. Photo: Cheong Loong Fah. group of animals. those aeshnid species in the genus gomphids, especially the swirling skir- Gynacantha. Like a conjurer’s trick, mishes of gomphids in their territorial tails, like the very common Common of the forest canopy, defying observa- these large, swift-flying hawkers appear battles. They make incredible twists Flametail Ictinogomphus decoratus. While tion. Even those that are not arbo- ragonflies are truly kings largely unchanged throughout evolu- from the dark inner space of the for- and turns, seemingly able to make 180 the club itself would seem to carry an real tend to be extremely wary and are of the air. One of the tionary time. It belongs to the family est during this moment of transition degree turns at full speed in little more energy cost in long-distance flight, it inclined to take evasive action very most majestic in appear- Aeshnidae, which is considered to be between day and night. They create than their own body length. They make might act as an excellent counterbalance quickly. The result is that except for a ance is the Giant Hawker one of the most archaic indeed, evi- an active kinetic pattern in the dim aeshnids look slow! When gomphids are to enable tight high-speed turns. Some few common species, many gomphids DTetracanthagyna plagiata. Its wingspan denced by the fact that, like damselflies, evening landscape with their tireless and present, there is always a sense of drama gomphids lack clubs but have rather elude even the most experienced odona- that can go up to a whopping 160mm, females possess well-developed oviposi- energetic flights, yet they always have a in the scene. As they launch their long long abdomens, which might serve the tologists and avid naturalists. Most are which is larger than that of a sunbird. tors with which to insert their eggs into slightly unreal and supernatural appear- slingshot trajectory high into the blue same function of keeping the high-speed pronounced “rarely seen in the wild”. Watching this enormous creature flying plant tissue or soil. Damselflies hark ance. While watching dragonflies by the sky, they scorch the air with the power turn under control. In Singapore, Ris’ Clubtail about in the swamp forest, it easily feels back about 300 million years. It was sun-dappled streams has its charm and and speed of their flight. Gomphidae is one of the more Leptogomphus risi and Malayan as if one is transported to a lost world. the time of invertebrate gigantism when romance, beholding these spectral forms Gomphids are sometimes given speciose families, yet the least well Spineleg Merogomphus femoralis are Indeed, T. plagiata belongs to an the wingspan of the extinct dragonfly appearing at dusk in the silent shade the common name of clubtails because known. Many gomphids forage high recent discoveries. The former is ancient noble lineage that has remained order Protodonata exceeded 700mm. also has a mysterious allure. quite a number of gomphids have club- above the vast unexplored green ocean classified as rare and local by Orr 8 Nature Watch Jan - Mar 2010 Jan - Mar 2010 Nature Watch 9 (2005), whereas for the latter, only a Dragons Beware— but an illusion; they are ephemeral habi- single male specimen is known from Preys And Predators tats after all, liable to dry up after the Malaysia. The two Burmagomphus spe- Some of the best habitats for watching monsoon rains. cies, Splayed Clubtail B. divaricatus and the spectacle of odonate life are at those Here in these rainwater-filled Lesser Splayed Clubtail B. plagiatus, are rainwater-filled low-lying areas like Tuas basins, as elsewhere, one can observe only recorded from Singapore in their and Marina East. It is a special moment two main modes of dragonfly hunting. larva form; no adults have been seen in when one arrives early in the morning The fliers catch and typically consume the wild. hours. The mist blurs the sense of time their prey while flying, while the perch- Looking through many of the and place, and all reminders of man are ers take off from an observation post, Peninsular Malaysia species, we find lost. Then the scene changes as the sun catch their prey and return, often to the many gomphid species whose status rises. As the air is heated up, the drag- same spot, and consume it. Many drag- are also pronounced as rare, such as onflies are stirred into frenzied action. onflies are strong and fast fliers, capable A Blue-throated Bee-eater (Merops viridis) Acrogomphus malayanus, A. minor, of reaching speeds of up to 50-60 km/h. with a dragonfly along the Nee Soon pipe- This sense of urgency seems not just a line trail. Photo: Morten Strange Onychogomphus duaricus, O. thien- response to the rise in temperature, but Their wings have a sophisticated archi- emanni, O.aemulus, etc. We suspect that a pattern of life characteristic of dwellers tecture of veins, which ensure that the some of these species could be present of ephemeral habitat. The timelessness wings are stable enough to bear such in Singapore too. of these marshes in the morning mist is speeds. On the other hand, hidden amidst the lush aquatic vegetation are many delightful Lilliputian damselflies, which are all perchers. While damselflies are slower, they are capable of exquisite wing control that facilitates forward- Charming Flashwing (Vestalis amoena) feeding on a cranefly. Photo: Cheong Loong Fah. reverse flight and deft maneuverability. Except for some specialists, most odonates are opportunistic foragers and have a catholic diet. However, as prey, A Blue-tailed Bee-eater (Merops philippi- flies and mosquitoes (dipterans) out- nus) has just captured a Saddlebag Glider number all other taxa. The celebrated (Tramea transmarina). Photo: Lee Tiah Khee. naturalist W.H. Hudson once described how, on the pampas of Patagonia, the appearance of a foraging dragonfly was welcomed by travelers, because it resulted in the instant departure of the Some odonates are Common Flametail (Ictinogomphus decoratus) is by far the commonest member of its fam- known to take large ily. Photo: Cheong Yu Jia. prey, even equal to their own body size, A Pied Fantail (Rhipidura javanica) has the most dramatic grabbed a female (Brachythemis contami- being cannibalism. nata). Photo: Wei Luen Chan. clouds of mosquitoes and blackflies that had been pestering them. Unfortunately, here in Singapore, the effect of dragon- flies is not as dramatic in terminating the flight of the mosquitoes. Some odonates are known to take large prey, even equal to their own body size, the most dramatic being can- nibalism. For instance, the libellulid Variegated Green Skimmer Orthetrum sabina and the coenagrionid Ornate Coraltail Ceriagrion cerinorubellum both Robber flies in the family Asilidae are exhibit strong tendency for cannibalism. also a threat to dragonflies. Here one has The locally rare Banded Hooktail (Paragomphus capricornis) emerging in the morning captured a Diplacodes sp. Photo: Cheong hours. Photo: Cheong Loong Fah. The term is here used in its zoological Loong Fah. An Orthetrum sabina feeding on a Tyriobapta torrida. Photo: Cheong Loong Fah. 10 Nature Watch Jan - Mar 2010 Jan - Mar 2010 Nature Watch 11 meaning, referring to a species eating Some odonate species occur in sev- members of its own kind, not always to eral colour forms which are genetically species level.

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