Damselflies from the genus Pseudagrion come from a large widespread subfamily Pseudagioninae. We have four species here including a very rare one, Pseudagrion rubriceps (Orange-faced Sprite) which now seems to exist only at the pond in Toa Payoh Town Park.
I saw three relatives in Nairobi. One of them is Pseudagrion salisburyense (Salisbury Sprite) that has a range from interior South Africa to east, central and western Africa.
The last Pseudagrion species can’t be identified with certainty. Its either P. spernatum or P. kersteni.
Ceriagrion is another large genus but only two species are in Singapore. Ceriagion chaoi (Fiery Coraltail) in Singapore is very much like Ceriagrion glabrum (Common Citril) from Africa. Their colour scheme is very similar but C. chaoi has a brighter red abdomen and olive thorax.
Dragonflies of the genus Trithemis are from the subfamily Trithemistinae or commonly called Dropwings. There are more than 50 Trithemis species worldwide, and they are essentially African but five have made it to Asia. Singapore has three species. One example is Trithemis festiva (Indigo Dropwing). Here, this species is predominately stream loving and have adapted very well to large canals and storm drains.
In the UN compound, I observed four species, one more than the whole of Singapore. The four are: Trithemis arteriosa (Red-veined Dropwing), Trithemis cf. dorsalis (Dorsal Dropwing), Trithemis stictica (Jaunty Dropwing) and the prettiest of the lot Trithemis kirbyi (Kirby’s Dropwing).
The widespread genus Brachythemis is from the subfamily Sympetrinae. Singapore has one representative, Brachythemis contaminata (Common Amberwing). Wherever B. contaminata occurs, they are always in great numbers and have a habit of flying close to the ground especially the females and immature males.
In Africa, Brachythemis dragonflies are also known as Groundlings. One species from Nairobi is Brachythemis leucosticta (Banded Groundling). Males have banded wings while females have clear wings.
Probably the most common dragonfly genus in Singapore is Orthetrum (subfamily Libellulinae). We have five species, all of which can be easily seen. In Asia, some Orthetrum species have evolved reddish colour in mature males. However pruinosed blue in mature males is more common in the genus, for example our Orthetrum luzonicum (Slender Blue Skimmer).
African Orthetrum species are mostly pruinosed blue Skimmers thus making their identification much more difficult compared to in Singapore. I saw one species in Nairobi, Orthetrum julia (Julia Skimmer) where an immature male has greenish thoracic markings.
Aeshnids of the genus Anax are highly territorial. While in Nairobi, I spotted one big dragonfly speeding around a pond in a patrolling flight and immediately I knew it is an Anax. Very fortunately, it perched and I got a clear picture of this handsome Anax imperator (Blue Emperor). It is positively more colourful than Singapore’s Anax guttatus (Emperor). And a bonus, an ovipositing female was sighted the next day.
Aside from those highlighted here, I observed 15 species in total. It was great to see those African relatives. There’s much more to learn on dragonflies knowledge beyond Singapore. Furthermore through these sightings I got acquainted with Klaas-Douwe B. Dijkstra and Viola Clausnitzer. Both of them are experts in African dragonflies and very friendly in helping to confirm the species. Not forgetting Warwick and Michele Tarboton who generously sent me their guidebooks before I left for Kenya.
Hence local dragonfly lovers should take all opportunities to spot dragonflies beyond Singapore. Remember, there’s about 5700 species in the world!
Pictures taken at: Toa Payoh Town Park, January 2009; Venus Trail, September 2009; Nairobi Kenya, May 2010; Bishan Park, July 2010; Kranji Marsh, July 2010
References:
Silsby, J., 2001. Dragonflies of the World, CSIRO Publishing, Victoria, Australia.
Tarboton, W. R. & M. Tarboton, 2005. A Fieldguide to the Damselflies of South Africa. Privately published.
Tarboton, W. R. & M. Tarboton, 2009. South African Dragonflies. A Quick Guide. Graphic Touch Guides, South Africa
This aspect of larvae ecology is rather well known. There are several studies showing larvae inhabiting small streams or seepages in forest can have a diminished dependence on water. Some species in Japan live among wet rock and mosses beside streams, a species in Himalaya hang around wet ferns near waterfalls and one species from New Caledonia clings onto the underside of moist leaves away from any water body.
After capturing, the larva will occasionally move completely out of water to consume the prey. I notice the bigger the shrimp, the more likely it’ll move above water for consumption. And this becomes more frequent as the larva grows.
Those with a phobia for things creepy and crawly will find this larva utterly hideous. It is now almost entirely black, having adapted its colour to the surroundings; it currently measures about 6cm in length; and has a dragon-like frontal appearance. It might look monstrous but once emerged into adult, it will become the biggest dragonfly in the world in terms of wingspan and weight.
Aeshnids are unlike most other dragonflies in that females will insert their eggs into plant tissue. This ovipositing mode is the same as damselflies. Aeshnid females have well-developed ovipositors to cut minute slits into plant tissue for egg insertion. This behaviour is seldom seen so I was very fortunate to witness an Anax guttatus with colleagues recently. The videos show a female ovipositing into the floating plant stem. A. guttatus, when not flying at speed, is quite easy to recognise with its overall greenish colour and blue pattern on the abdomen. Up close, it is a beautiful and impressive dragonfly.
