30 September 2009

New Taxon for Malaysia

New Taxon for Malaysia
Discovery of a new butterfly species on Pulau Langkawi - Dryas iulia

On a recent trip to Pulau Langkawi, members of ButterflyCircle chanced upon a species of butterfly that has hitherto not been recorded in Malaysia. On location at Tanjung Rhu Beach, it was deja vu, as this was the place where I saw my first Leopard Lacewing (Cethosia cyane) back in 2001. Fast-forward to Sep 2009, another new species was spotted at almost the very same location where I saw the Leopard Lacewing!

A shot of the Tg Rhu Beach area where the pair of Dryas iulia was seen.

Whilst walking amongst the coastal vegetation, ButterflyCircle members Bobby Mun, Ellen Tan and I spotted a rather large orange butterfly fluttering amongst the wild flowers at low level. I instantly knew that this wasn't the usual Tawny Coster as the size and the flight characteristics were different. Upon closer examination, we found that the large orange butterfly, a male, was fluttering around a female of the same species which was feeding on the flowers.

The male, startled by our intrusion, beat a hasty getaway, and flew away towards the safety of the forested area. The female, however, continued with her unflustered fluttering amongst the herbage, looking for nectar from the wildflowers. As she continued to feed, we observed that her wings were badly tattered. Despite that, she was still able to fly nonchalantly from flower to flower, allowing the three of us to fire off several shots, as she paused at various flowers to feed.

After a short while, she also sensed our presence, and flew off towards the tree canopy and disappeared into the forested area.

Upon closer scrutiny of our photos, I realised that this unknown butterfly could very well be a new record for Malaysia. (Subsequent confirmation by Dr Laurence Kirton of FRIM established that this is a new record for Malaysia) The species was a Dryas iulia (or commonly known as the Julia Heliconian or Julia Butterfly). From literature research on the Internet, about 15 subspecies of Dryas iulia have been described. The species is native to South America, occuring from Mexico to Colombia and Brazil, and has a range reaching the North American states of Florida, Texas and as far north as Nebraska.

The Julia Heliconian is the sole representative of the genus Dryas and is described to be a fast flyer and a rather large butterfly with a wingspan ranging from 82 to 92mm. Its elongated forewings are characteristic of this species, whilst the hindwings are small in relation to the forewings.

Two shots of Dryas iulia taken at the Phuket Butterfly Farm

I have observed this species bred at the Phuket Butterfly Farm when I was on vacation in 1997 and from the numbers flying around within the enclosure, it appeared to be an easily bred butterfly, even in captivity. I also later saw a few individuals flying outside the enclosure, at the garden of the hotel where I stayed, the Allamanda Laguna Phuket.

A male free-ranging Dryas iulia shot recently on the Thai resort island of Koh Samui

Over at Koh Samui, ButterflyCircle member Leslie Day has also regularly encountered Dryas iulia flying freely on this resort island on the eastern coast of the Thai Peninsula. It is interesting to note that this species, probably brought in from Brazil to be featured at a Thai Butterfly Farm at Phuket (and likely others) has escaped and spread throughout southern Thailand in the late 90's and early part of this decade.

A shot of a female Dryas iulia taken at Koh Samui. The markings on this individual correspond very closely to the one shot at Tg Rhu Beach at Langkawi

The Julia Heliconian is described as a tenacious survivor that is distasteful to birds, and has a long life span (some reports have it at 3-4 months!). Its host plants are predominantly species of Passifloraceae, and it is highly likely that in Thailand, the species shares the same host plant as the Leopard Lacewing and the Tawny Coster - Passiflora foetida. Indeed, this host plant was also present at the forested patch at Tanjung Rhu Beach.

It is also to be highlighted that the species was not featured in Pisuth Ek-Amnuay's Butterflies of Thailand 1st Edition, suggesting that the Julia Heliconian may be a very recent immigrant to Thailand, and not considered as part of Thailand's butterfly fauna. However, its appearance as a free-ranging species in parts of southern Thailand would suggest that it has been able to survive and thrive in our SouthEast Asian environment that is somewhat climatically similar to its region of origin in South America.

Having found a pair of the species fluttering freely on Pulau Langkawi, a not-too-long distance from where I first encountered the species on Phuket Island in Thailand, it does not come as a great surprise that this robust butterfly has now spread southwards into Malaysia, and may have colonised some areas between Thailand and Malaysia.

It now remains to be seen how fast this species can move southwards down Peninsula Malaysia like the immigrant Leopard Lacewing and Tawny Coster, both of which eventually ended up in Singapore (and are now "permanent residents") about 8-10 years after first being spotted in the northern part of Malaysia.

Will this South American beauty end up as a resident species in foreign talent-friendly Singapore? Keep your eyes peeled for this species as it begins to samba its journey southwards.

Text by Khew SK ; Photos by Bobby Mun, Ellen Tan, Khew SK, Leslie Day and Simon Sng.

Acknowledgements : Special thanks to Dr Laurence Kirton of FRIM who confirmed that the photos were indeed of Dryas iulia. However without a specimen to examine, we are unable to confirm the subspecies that now occurs on Pulau Langkawi. It is most likely the same subspecies that has been bred in Thailand, but that remains for other researchers to establish in the near future.

26 September 2009

Life History of the Rustic

Life History of the Rustic (Cupha erymanthis lotis)

Butterfly Biodata:
Genus: Cupha Billberg, 1820
Species: erymanthis Drury, 1773
Subspecies: lotis Sulzer, 1776
Wingspan of Adult Butterfly: 55mm
Caterpillar Local Host Plants: Flacourtia rukam (Flacourtiaceae)
, F. inermis (Flacourtiaceae)

A Rustic puddling on wet ground in the nature reserves.

A Rustic perching on a leaf.

Physical Description of Adult Butterfly:
Above, the forewing is orange brown in the basal area and black at the apical area with several subapical spots lying within; in between there is a broad pale yellowish discal patch containing three or four dark brown spots in spaces 2, 3 and 4. The hindwing is mainly orange brown and have narrow marginal, submarginal and postdiscal bands with a discal series of black spots in spaces 2 to 6. Underneath, the wings are much paler and the apical area in the forewing is pale brownish. On the forewing, there is a narrow discal line bordered outwardly by a series of black spots, and on the hindiwng there is a postdiscal pale lunular band and a discal series of pale lunules bordered outwardly by black spots.

Another puddling Rustic in the nature reserve.

Field Observations of Butterfly Behaviour: This species is rather common in the Central Catchment Nature Reserve. The fast flying adults can be frequently seen flying around shrubs and bushes found alongside various trekking trails in the nature reserve. However, on the wing, one can easily confuse it with Banded Yeoman (Cirrochroa orissa orissa). The restless adults make it rather difficult to photograph them in the field. Rare opportunities to do so only arise when they stop briefly to visit flowers or to puddle on wet grounds.

Early Stages:
The local host plant found in the Central Catchment Reserve, Flacourtia rukam, is a small evergreen tree with thorny stems and branches. Its leaves are elliptic and crenulate, and reddish brown to red when they are young. Its flowers are small and unisexual and occur in axillary clusters. The pink to reddish berry is globose and is good for making jam. The caterpillars of the Rustic feed mainly on young leaves of the host plant.

Local host plant: Flacourtia rukam in the nature reserves.

A mating pair of the Rustic.

The eggs of the Rustic are laid singly on the undersides of young leaves, typically on a young sapling of the host plant. The white or pale yellow eggs are somewhat globular in shape and more produced near the top where the micropylar is. The surface is marked with small pits which are roughly hexagonal higher up and rectangular lower down. Each egg has a diameter of about 0.9mm, and a height of about 1mm.

A female Rustic ovipositing on a young sapling of Flacourtia rukam.

Left: Fresh egg of the Rustic. Right: Mature egg of the Rustic.
Diameter: 0.9mm; height: 1mm.
The egg takes about 2.5 days to hatch. The young caterpillar emerges by eating away part of the egg shell. The rest of the egg shell becomes the first meal for the newly hatched, which has a cylindrical and creamy white body covered with many small tubercles and short setae. In the abdominal segments, reddish and yellowish internal structure can bee seen through the translucent skin. The head capsule is yellowish brown with the front portion black.

Two views of a newly hatched caterpillar of the Rustic, length: 2mm.

The 1st instar caterpillar feeds on the lamina of young leaves and between feeds, it typically rests on leaf underside against the midrib. As it grows rapidly in this instar, the base body changes to yellow, and thoracic segments and posterior abdominal segments turning reddish. After reaching about 4mm in 1.5-2 days, the caterpillar moults to the 2nd instar. Noteworthy is the prominent enlargement of a number of tubercles at the base of the setae towards the end of the 1st instar. These tubercles will give rise to the branched processes in the 2nd instar.

Two views of a 1st instar caterpillar, length: 3mm.

Two views of a late 1st instar caterpillar, prior to its moult, length: 4mm.

The body of the 2nd instar caterpillar is yellowish brown in base color with a green undertone. As in the late 1st instar, the thoracic segments and last few abdominal segments are mainly reddish brown. Long and branched white processes run along the length of the body. On each side of the body, there are three series of such processes: One occurs dorso-laterally, one super-spiracularly and the last, the shortest, runs sub-spiracularly. The head capsule is yellow with two large black patches on the front portion. This short instar lasts about 1.5 days with the body length reaching about 6mm.

Two views of a 2nd instar caterpillar, length: 6mm

Three snapshots of the moult from the 2nd instar to the 3rd instar.
Top: late 2nd instar; Middle: with old skin just shredded; Bottom: with the new processes inflated.

Moulting to the 3rd instar and the inflation of the new processes at 4x speed.

The 3rd instar caterpillar has the dorso-lateral and super-spiracular processes black in color. A white band links up the base of the sub-spiracular processes. Above this white band, the body color is dark red with a green undertone. This instar takes about 1.5 days to complete with body length reaching about 10-11mm.

Two views of a 3rd instar caterpillar, late in this stage, length: 11mm.

Compared to the 3rd instar, the 4th instar caterpillar has proportionately longer processes. Otherwise, there is essentially no change in external appearance. The 4th instar lasts 3 days with the body length reaching about 18mm-20mm.

Two views of a 4th instar caterpillar, length: 16.5mm.

Two views of a 4th instar caterpillar, late in this stage, length: 20mm.

The 5th and final instar is similar to the 4th instar caterpillar except for the appearance of numerous small white spots on the body surface and that the sub-spiracular processes are black in their distal halves.

Two views of a 5th instar caterpillar, length: 27mm.

Frontal view of the head capsule of a 5th instar caterpillar.

The 5th instar lasts for 3 to 3.5 days, and the body length reaches up to 26-28mm. On the last 0.5 day, the color of the entire body changes to yellow and then eventually to lawn green or yellow green. The caterpillar ceases feeding and wanders around. Eventually it stops at a spot on the underside of a leaf, and spins a silk pad from which it hangs vertically to take on the pre-pupatory pose.

The 5th instar caterpillar with its body color changed at the end of this instar.

Two views of an immobile pre-pupatory larva.

Pupation takes place about 0.5 days later. The pupa suspends itself from the silk pad with no supporting silk girdle. It is entirely green. Dorso-laterally there are five long pairs of red and black-tipped processes, and five pairs of small tubercles. Each long process has a broad silver-colored base. There is also a slender silver patch along the leading edge of the wing pad. Length of pupae: 18-19mm.

Two views of a shining pupa of the Rustic.

Two views of a mature pupa of the Rustic. Note the prominent discal patch in the black wing pad.

After about 4 days of development, the pupal skin of the mature pupa turns translucent and the broad discal patch on the forewing upperside become discernible as a result. The eclosion event takes place the next day.

A newly eclosed Rustic drying its wings at its pupal case.

A newly eclosed Rustic resting on the young leaves of its host plant.

  • The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, The Malayan Nature Society.
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 1st Edition, 2006
Text by Horace Tan, Photos by Federick Ho, Khew S K and Horace Tan

18 September 2009

Languid Langkawi

Languid Langkawi
3 Days of Butterflying on a Tropical Island Paradise

The Helang or Eagle, stands guard at the entry of the harbour at Kuah Town, Langkawi

Think searing blue skies softened by tufts of cloud, white sand beaches washed in clear green seas, wandering water buffaloes in light green paddy fields, and eagles soaring over majestic mountain ridges reaching up into the clouds… and it is easy to understand why Langkawi is popularly known as a tropical paradise.

Pulau Langkawi is the largest island in an archipelago of 99 islands off the mainland coast of northwestern Malaysia and is part of the state of Kedah. Langkawi has a World Geopark status by UNESCO with Machincang Cambrian Geoforest Park, Kilim Karst Geoforest Park and Dayang Bunting Marble Geoforest park (Island of the Pregnant Maiden Lake) being the 3 most popular parks.

That being said, we averted from the touristy areas and banked our chances of encountering rare butterflies on trails less travelled. Our little group of butterfly-philic photographers consisting of Sunny Chir, lepidopterist Khew SK, Bobby Mun and Ellen Tan, were less averse to leech bites than disruptive crowds of excited tourists.

After a short 90 minute flight from Changi Airport, our SilkAir flight landed at the Langkawi International Airport in the early evening. Our car rental driver met us as we emerged from the airport, and he drove us to the nearby Langkasuka hotel where we were staying. Dinner was at a local seafood place at Panti Cenang. Langkawi is also a paradise for alcohol-loving tourists, as a can of Tiger beer costs only RM1.60 (that's about S$0.65 a can!)

Day 1 : Gunung Raya

Our first day saw us up and about early, and the first thing we did was to look for a petrol station to make sure that we don't end up gas-less somewhere in the middle of Langkawi. After orbiting around town, and navigating via the map and road signs, we ended up back at the hotel for breakfast! We soon learnt quickly that you either referred to the map OR the road signs, but not both, otherwise we'll orbit hopelessly around the island.

We headed for Gunung Raya, and the first site we trundled up in our struggling little 3 gear car (Proton Wira Auto has only 3 forward gears) was the 881-metre high Gunung Raya, the tallest natural feature on Langkawi. The mountain is believed to be the cursed form of a giant, known as Mat Raya, who once lived on the island.

Gunung Raya’s peak was persistently shrouded in mist and cloud while we were there and the weather on its winding roads switched as suddenly from sunshine to rain to sunshine as quickly and dramatically as a time lapse recording of seasonal rains in African savannah.

Sunny getting rid of the pesky blood-sucking leeches!

In spite of the erratic weather, Helens abounded in numbers, Chestnut tigers wafted by and there were plenty of butterflies to shoot.

Tanjung Rhu Beach

Just after 1pm at the urging of Ellen's growling tummy, we bade farewell to Gunung Raya and headed towards the Tanjung Rhu Beach. This was an area that I visited some years back in 2001 and also where I recorded the presence of the Leopard Lacewing (Cethosia cyane), which eventually worked its way down the Malay Peninsula and Singapore.

As fate would have it, history appears to repeat itself when our group found another new species of butterfly (a pair of them actually) fluttering around the low wild flowers just a short distance from where I found the first Leopard Lacewing nearly 8 years ago! A quick check with our Malaysian expert, Dr Laurence Kirton, confirmed that this species is new to Malaysia! A special blog article will feature this species shortly.

A languid scene at Tanjung Rhu Beach

The Tanjung Rhu Beach area is very much as I had remembered when I visited it in 2001, and the Lantana, Snakeweed and other wild flowers were blooming! However, probably due to the late hour of the day, there were few butterflies around. So we ended up taking the breathtaking landscape shots of the area. But the discovery of a new taxon for Malaysia made our day as we called it quits and headed back to our hotel.

We drove off to Kuah Town for dinner, and visited some of the more 'touristy' areas of Langkawi.

A serene sunset scene from the main ferry point at Kuah Town

Day 2 : Telaga Tujuh Waterfalls

The next morning, we had breakfast at the hotel and headed out to the nearest of the waterfalls - Telaga Tujuh (or Seven Wells) Waterfalls. The area was at the base of Langkawi's Cable Car attraction. There were also horse-riding and elephant-riding attractions in the area.

The lowland forest trails at the base of the mountains proved to be a good butterfly-hunting ground. Despite the rain-sunshine-rain-sunshine weather again, the group had a relatively satisfying time shooting the many species in the forested areas. Strangely though, there were few of the usual Papilionidae puddlers along the open sandy paths as compared to areas like Endau Rompin or Fraser's Hill.

Day 3 : Telaga Tujuh Waterfalls - Part 2

A group shot of the four intrepid adventurers on Langkawi

On our last day on Langkawi, we decided to do the Telaga Tujuh Waterfall trails again. This time around, the weather was more stable and sunny, and we were able to shoot more species to add to the previous day's tally.

However, the butterflies seem to be more skittish and frustratingly hard to shoot as they enjoy the warmer weather.

We returned to the hotel just after mid-day, and after a quick shower, had lunch at the little restaurant at the hotel again - but not before Bobby and Ellen had their fair share of frolicking in the hotel's swimming pool, whilst the two older fogeys wandered around shooting whatever came across as interesting to shoot.

Some additional points to note :

Always wear your seatbelt (both front and back seats) whenever you're in a car, unless you want to contribute generously to the local constabulary's retirement fund. Also, the speed limit throughout Langkawi is 60 km/h (except for the main highway, where it is 70 km/h). Police roadblocks are frequent and turn up at the most unexpected areas - mostly where unsuspecting tourists are likely to let their guard down, and end up donating to the policemen's charitable cause.

Our SilkAir flight back to Singapore was at 8:40pm and by the time we got back to Changi Airport, tired but generally happy (to leave any ghosts that were supposed to be in the hotel bedroom behind) to have visited one of Malaysia's island paradises that is home to many butterfly species.

Text by Khew SK & Ellen Tan : Photos by Bobby Mun, Ellen Tan, Khew SK & Sunny Chir