(published in Agrion vol. 9, number 2)

DEADLINE: Contribution for the next issue of Echo should be sent to Vincent Kalkman (Kalkman@naturalis.nl) before 1 November 2005.

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The number of pictures present on the Asian Dragonfly internet site (www.asia-dragonfly.net) has steadily increased in the last few months. So far more than 60 persons have contributed and at the moment (1 June 2005) 1.000 pictures of 282 species are available. Most of the pictures are from common and widespread species but the site contains also numerous photos of rarer and more interesting species. Some examples of pictures especially worth taking a look at are:
- Archineura: both species of this genus of large calopterigids are depicted. A. incarnata is specially remarkable due to its reddish wing-base.
- Chlorogomphus: Most species of the genus Chlorogomphus combine a large size with a spectacular wing pattern. In total 9 pictures of 4 species are present, among which is a picture of a flying Chlorogomphus nakamurai.
- Philoganga: Philoganga is a small genus of rather weird damselflies. Two species are present on the internet site and are worth taking a look at. (P. robusta and P. vetusta)
- Cyclogomphus gynostylus: The site contains pictures of no less than 29 gomphids species many of which are poorly known. An example of such a species is the picture of a fresh female Cyclogomphus gynostylus.
- Rhinagrion philippinum: Sadly not many pictures have been published of the many endemics present in the Philippines. Luckily a few are now present on Asian-Dragonfly. One of the most interesting is a picture of Rhinagrion philippinum.
- Tetracanthagyna plagiata: during their trip to the National Park of Endau-Rompin Keith Wilson and Eric Gibert were able to take a good picture of a female Tetracanthagyna plagiata, the dragonfly boasting the largest wingspan of all:

Recently the site has been used by birdwatchers living in SE Asia to identify the pictures they had previously taken: hopefully it will get some of these local birdwatchers more actively involved in dragonflies.

Haruki Karube: Ten years ago I started working on the dragonfly fauna of Southeast Asia concentrating on the fauna of Vietnam. The first results of the fieldwork in Vietnam have been published in the last years. These papers include an update on the aeshnids present in Vietnam. Twenty-one species of this family have so far been found in Vietnam. Six of these were recorded as new for the Vietnamese fauna in my recent papers, among these is one species new to science. Also included in these papers are the descriptions of the first female some Planaeschna species and the redescription of P. tamdaoensis Asahina. At the moment I am working on papers on Gomphidae and Cordulegastridae which will hopefully be published this year. I spent a long time on a revision of Chlorogomphine-group and hope it will be finished next year. This revision will include about 20 new species and will deal with a large number of taxonomic problems in this group.
Last year I had a serious allergy after been bitten by ‘Bull Ants’ during fieldwork in Australia. After that, I also had a food allergy and so it is difficult to do any collecting at the moment. I am recovering from this and hope soon to do fieldwork in Southeast Asia again.
I spent a long time on a revision of Chlorogomphine-group and hope it will be finished next year. This revision will include about 20 new species and will deal with a large number of taxonomic problems in the group.

Naoto Yokoi: Since 1994 I started investigating the dragonflies present in the mountainous regions of Laos. As a result, 195 species are presently known from Laos among which are four Amphipterygidae, 15 Platycnemididae, 10 Calopterygidae, 34 Gomphidiae, 21 Corduliidae. Besides these I have specimens of 30 or more species not yet published from Laos.
I visited Bolovens plateau, Sekong and Attapu, southern Laos to collect dragonflies in April this year. Dragonflies were relatively scarce due to the strong dry season. However some new and interesting species were found (Coeliccia montana?, Aristocypha sp., with orange wing!, Macromia cf moorei, Hemicordulia sp. nov.? etc.).
Recently the building of dams has strongly increased in Laos resulting in large scale damage to the natural environment. So for some areas the next few years will be the last opportunity to study the dragonfly-fauna.

Emergence study in Hong Kong wetlands Graham Reels (gtreels@asiaecol.com.hk)

As part of my ecological consultancy work in Hong Kong, I am monitoring dragonfly populations at some 27 ponds. About half of these ponds were formerly commercial fishponds, which are now being “ecologically enhanced” in mitigation for wetland loss caused by construction of a new railway line, while others are newly-created wetlands, which have been constructed for the same purpose.

The primary function of these wetlands is to provide suitable habitat for waterfowl, and none (regrettably) have been specifically designed for dragonflies. However, the habitat requirements of these faunal groups do overlap to some extent, and many individual ponds have proven to be very good for dragonflies, with more than 20 species recorded as adults.
In order to gain a clearer understanding of the value of these wetlands for dragonflies, I have been studying emergence by regularly patrolling the pond edges and collecting and identifying the exuviae. This approach is, however, only able to provide qualitative data, and there is insufficient funding to conduct such sur¬veys more than twice per month in each pond. This is unfortunate, since there is tremendous scope to generate much useful information on the colonization of wetlands by lentic dragonflies in Hong Kong, and their seasonality and voltinism.

In February of 2004, in order to overcome the limitations of my funded survey work, I initiated a voluntary study of dragonfly emergence from two former fishponds and two newly-created ponds, using a combination of emergence screens and traps. After tagging some 50 anisopteran exuviae, of various species, to determine their persistence in the field, I concluded that I needed to check these apparatus two times per week in order to be confident that I was not losing a significant amount of data. I have also been intensively studying another constructed pond, about half a hectare in size, by collecting all exuviae present on the vegetation two times per week. This pond has yielded information which has been genuinely surprising to me – most notably, the sequential emergence of larger odonates over the period February to July (Anax guttatus and A. parthenope, followed by Ictinogomphus pertinax, followed by Epophthalmia elegans, followed by Sinictinogomphus clavatus) – an emergence pattern which, at this stage, seems peculiar to this pond.

Since the beginning of 2005 I have expanded this study to several more ponds. I hope to get emergence data over a period of several years in these ponds, but already find it hard to free up enough spare time. The good news is that my employers are starting to take an interest, and will hopefully permit me to use normal working hours to pursue the study in the future. I am still hampered by the fact that I am not affiliated to a university or research institution, but if I can use this forum to gain advice and information from others who have conducted similar studies, this will be of great help to me. I am unsure if anyone has undertaken such studies in tropical Asia (I have not found any references in the literature, but maybe I haven’t looked hard enough), but would be delighted to hear from anyone who has.

Endau-Rompin 20-24 July ‘04 Keith DP Wilson (wilsonkd@ntlworld.com) & Eric Gibert (ericgibert@yahoo.fr)

In October 2003 Eric Gibert, who started the Asia-Dragonfly.net website two years ago, asked me if I would be interested in helping produce a booklet on the dragonflies of Endau-Rompin National Park, Johor Bahru, Malaysia. Eric reminded me that Endau-Rompin was host to the largest Anisopteran in the world, namely Tetracanthagyna plagiata Waterhouse, but we both needed no encouragement to visit this huge, relatively pristine, lowland rainforest. The invitation came from Vincent K.K. Chow of the Malaysian Nature Society and Scientific Consultant to the Johor National Park Corporation. Vincent has already initiated odonate studies at Endau-Rompin. Eventually, after a couple of cancelled visits, we found a period in summer 2004 when Eric and I could both make the trip to the Park. On the 20th July 2004 we met up with Vincent and Mohamid Basir B. Mohamed Sali, Director of the Johor National Park Corporation, at the Johor Parks Head Office in Johor Bahru. After fruitful discussions, we were soon whisked off to Endau-Rompin, which is a four-hour, part four-wheel drive, journey from Johor Bahru. During our short five-day visit we received superb hospitality from the Johor National Park Corporation and the Malaysian Nature Society for which we are both extremely grateful.

Endau-Rompin National Park is located on the Johor-Pahang border and covers an area of some 48,905 hectares (800 sq. km). It is the second largest national park in peninsular Malaysia after Taman Negara and comprised of lowland forest with several prominent sandstone plateaus rising up to ca 700 m altitude. It is the headwater catchment for several rivers including the Endau, Selai, and Jasin rivers. The wet season officially begins on 15th October and lasts for three months with the Park closed during November and December.

Our visit coincided with perhaps the driest period of the year and should have been relatively dry, but it rained most of the five days we were in the Park. Endau-Rompin is after all a tropical rainforest and as such it experiences rainfall throughout the year. Despite the all year round rainfall it was self evident that many dragonflies adopt a seasonal lifestyle. We encountered no adult corduliids such as Macromia or Idionyx and very few aeshnids and gomphids. Only small numbers of dragonflies were observed feeding at dawn and dusk indicating the main adult flying period for many dragonflies such as the corduliids and aeshnids probably occurs during the October to January wet season. We nevertheless encountered 49 species of Odonata and witnessed some interesting dragonfly behaviour on the days when we enjoyed long periods of sunshine.

The behaviour of interest involved Rhinagrion mima Karsch which is a stout, strikingly coloured member of the Megapodagrionidae. Males are black with a bold pattern of pale bluish green spots on the thorax and basal abdomen and bright orange-red dorsum to abdominal segments 7-10. Males involved in territorial disputes, located at favoured, sunlight spots beside sizable flowing streams, angled the tips of their orange-red abdomens upward and flew side by side for long periods, often slowly rising up towards the adjacent forest canopy. The flights terminated when one of the males would fly rapidly to take up a prominent position at a favoured sunlight spot, with the losing male taking up a position several metres away in a less favoured position. The disputes were often quickly resumed and in one case continued for over twenty minutes. One female was observed ovipositing into mossy vegetation, which was growing on a vertical bank, located some 1.5 metres above the stream surface, adjacent to a clump of screwpine (Panadanus sp.) with an extensive aquatic root system.

Another member of the Megapodagrionidae, Podolestes orientalis Selys was found in a teneral condition adjacent to a well-shaded, leaf-filled marshy pool, close to a small forest stream.

After three days fieldwork we had seen no sign of the charismatic Tetracanthagyna plagiata. At 21° latitude in China Tetragynacantha waterhousei McLachlan, 1898 exhibits a seasonal lifestyle. It emerges at the onset of the rainy season in late April, and is not found on the wing in late summer. We figured if Tetracanthagyna plagiata has a similar emergence pattern then we might not encounter any on the wing at Endau-Rompin during the July dry season. On our last fieldwork day we climbed up to one of the sandy plateaus in the hope of finding marshy ground but found no permanently wet areas. We did, however, find three species of pitcher plant. Soon after returning to the lowland streams we encountered a female Tetracanthagyna plagiata settled on tall vegetation about four metres from the ground. Somewhat awestruck by its size and magnificent colouration we managed to take a few photos before it flew further up into the canopy and settled well beyond our reach. This species is one of the few examples where the female has wings with more extensive colouration than their male counterparts; a feature shared with Chlorogomphus papilio Ris, 1927 which, coincidently, has a wingspan almost as large as plagiata.
Tetracanthagyna plagiata has a wingspan of ca 162-163 mm, hindwing of 80-84 mm and a body length of 95-100 mm. According to the literature, it is an insect usually observed in fading light at sunset but our female was observed flying in well-shaded forest during late morning during a period of bright sunshine.

On returning to our accommodation we were treated to another exceptional sighting. We both observed at close quarters a large, ca 1 m length, sandy-white squirrel crashing through the canopy and leaping from tree branch to tree branch across our path. On researching this sighting it is apparent that we may well have observed a cream-coloured giant squirrel (Ratufa affinis Raffles, 1821). This squirrel has only previously been recorded from Singapore, where it is considered critically endangered and is listed on CITES appendix 2. Vincent Chow also reports that he has observed a giant white squirrel in Endau-Rompin.

Both Eric and I are resolved to return to Endau-Rompin during the wet season in the near future. It will be fascinating to contrast the activity and numbers of odonate adults observed in the dry season with future observations during the wet season.

The list of the 81 spp recorded during the first and second trip to Endau-Rompin is provided below in Table 1.

Table 1 . List of odonates recorded from Endau-Rompin during visits on 20-24 July 2004 and in January 2005.