Butterfly of the Month - February 2008

BUTTERFLY OF THE MONTH - JANUARY 2008

The Common Red Flash (Rapala iarbus iarbus)

In the spirit of the Lunar New Year celebrations, bright red is always an auspicious colour to start off the Year of the Rat 2008. Our feature butterfly this month is a small but speedy butterfly - the Common Red Flash.

The red colours of the upperside of the male of this species gives the common name to the butterfly. The wings are red with black margins in the males, whilst the females are a drab coppery brown. The underside is light grey with darker post-discal lines which are white-edged. There is a black tornal spot on the hindwing, which is orange-crowned. The tornal lobe is covered with bluish scaling. Both the males and females have a white-tipped black tail at vein 2 of the hindwings. The species has large jet-black eyes and black-and-white banded legs.

The Common Red Flash is not very rare, and where it occurs, several individuals are often seen together. In the early morning hours and also in the late afternoons on sunny days, the males can be seen frolicking amongst forested areas where they stop to open their wings to sunbathe. During other times of the day, they appear to prefer to stop with their wings folded shut. Feeding time is usually in the mornings where common wildflowers are the favoured nectaring plants.

As with the other species of the Rapala the Common Red Flash is a fast flyer, zipping from perch to perch with blazing speeds (and hence probably the name 'Flash'). The caterpillars of this species are known to feed on young shoots of the Rambutan (Nephelium lappaceum) and the Singapore Rhododendron (Melastoma malabathricum), where it feeds on the ripening seed pods.

The Common Red Flash can be found within the nature reserves in Singapore, as well as on the offshore island of Pulau Ubin, where it is sometimes common in open sunny areas where wildflowers bloom in abundance. They often stop to rest with their wings closed shut on their favourite perches in the undergrowth.

Text by Khew SK ; Photos by Sunny Chir

A New Lycaenidae species for Singapore!

ButterflyCircle finds a new Lycaenidae species in Singapore!

Some time back, in 2004, ButterflyCircle member Federick Ho shot a small Lycaenid which had our group wondering what whether it was an aberration of one of our local species, and we filed it in our UFO (Unidentified Flying Object) folder and forgot about it, as it did not appear to match anything in the books for any species flying in the South East Asian region.

In Feb 2005, another record shot of this strange Lycaenid was again taken by Federick, and this time, it did not appear to be an aberration. Internet searches turned up some similar looking species from the Australian region, but it did not appear that it would be possible for a small butterfly to migrate all the way from down under.

Then again in Nov 2006, another of our hardworking ButterflyCircle members, Horace Tan, shot this strange looking butterfly at one of our urban parks.

Finally, on Chinese New Year's Day, the Butterfly Fairy smiled on Federick Ho once again, but this time, besides being able to shoot the species again, he and Tan BJ sighted a small colony of this species, proving that it was not a wayward migrant or a one-off stowaway species that somehow got to Singapore. This had the group's members all excited, and on a weekend outing, we saw no less than half a dozen individuals - both males and females, flying around a flowering bush.

With the superior skills of our group of accomplished butterfly photographers from ButterflyCircle, the hitherto unknown species was finally recorded with clarity and sharpness, confirming what Federick and Horace shot earlier was not a phantom butterfly!

Internet searches found an Australian species of Nacaduba. This species, known as the Two Spotted Line Blue (Nacaduba biocellata) and the descriptions from several Australian websites, matched the UFO that we found in Singapore.

Description of the Two Spotted Line Blue : Male - upperside lilac with base dark blue ; Female - upperside dull brown with basal area variably suffused with blue. Underside pale brown with a series of dark brown spots and bands narrowly edged with brown and white. Each hindwing has two black subtornal spots with iridescent green scales and inwardly ringed with pale yellow brown.

The species is described as common and sometimes abundant in Australia, where its host plants are various species of Acacia. In Singapore, where the invasive Acacia auriculiformis - Earleaf Acacia, or the Northern Black Wattle or the Australian Wattle, grow wild, it is likely that the Two Spotted Line Blue has also adapted to feed on this species of Acacia. Indeed, at the location where this colony was found, there are a few Acacia trees nearby and the butterflies were seen to fly up towards the tree at times.

Given the physical appearance of this species, it is definitely one that has not been recorded in Singapore before. How it was able to 'migrate' this far from Australia is anybody's guess. But it is likely that human agency is involved, rather than natural migration. The species is therefore added to the Singapore Butterfly Checklist with the tentative name of Two Spotted Line Blue (Nacaduba biocellata) whilst further checks are being made with experts in the field - particularly the Australian lepidopterists.

Text by Khew SK ; Photos by Khew SK, Sunny Chir, Tan BJ, Sum CM, Federick Ho and Horace Tan

Butterfly Photography - Shooting the Eclosion of a Butterfly

Shooting the Eclosion of a Butterfly

For most butterfly photographers, shooting the sequence of the 'hatching' of an adult butterfly as it emerges from its pupa at the culmination metamorphosis, is something extremely difficult and and requires a lot of patience, but it is nevertheless very rewarding.

The correct terminology of a butterfly 'hatching' from its pupal case is eclosion*.

*Eclosion: The emergence of an adult insect from its pupal case, or the hatching of an insect larva from an egg. From the French éclosion, from éclore, to open.

Bobby Mun, a member of ButterflyCircle, demonstrates his skill and immense patience in shooting eclosion sequence shots of a number of butterfly species.

Shooting the Eclosion

Watching the butterfly cracking open its pupal case, climbing out and then pumping "blood" (the correct term for insect "blood" is haemolymph) into its wing veins as the crumpled wings expand into their final shape for flight, is fascinating. The process that traces the transformation of a leaf-munching caterpillar into a pupa which then ecloses into a beautiful nectar-drinking butterfly is one of the wonders of Nature.

Photographing the eclosion sequence requires a fair bit of understanding of the butterfly's early stages, and preparing the equipment and location for the final shoot. The pupa, which is usually firmly attached to its perch, can be set up against an appropriate background. The photographic equipment need not be anything elaborate, other than the camera, a dedicated macro lens, and a flash unit, all mounted on a tripod for stability.

Most species' pupae change colour and appear semi-transparent on the night before eclosion. Very often, the wing patterns are visible through the semi-transparent pupal shell. Butterflies, in general, eclose during the early morning hours, which can range between 5 am to 11 am. There are even some species which eclose in the late afternoon. Hence, an understanding of the biology of the species of butterfly being photographed, would reduce the frustration of waiting in vain for an eclosion which happens the moment you take a lunch break!

Once the equipment and the setting is prepared and ready, the photographer requires nothing else but to wait for the eclosion to happen. This is easier said than done, as one would require the "patience of a Saint ; and the luck of the Devil" to succeed with a good series of the eclosion sequence.

Typically, the eclosion process takes only 3-5 minutes (for some species, even shorter!), from the time the butterfly cracks itself out of the pupal shell and clamber out to hold on to a suitable perch from which it can settle into position to pump its haemolymph to expand its wings. The process of drying its wings before it is ready for its maiden flight can take a couple of hours or more, depending on the prevalent conditions of the location at which the butterfly ecloses.

Text by Khew SK ; Photos and Layout by Bobby Mun

Life History of the Malay Viscount

Life History of the Malay Viscount (Tanaecia pelea pelea)
An updated version of the life history of the Malay Viscount can be found by clicking this link.

Butterfly Biodata :

Genus : Tanaecia Butler, 1839

Species : pelea Fabricius, 1787

Subspecies : pelea Fabricius, 1787

Wingspan of Adult Butterfly : 70mm
Caterpillar Host Plant : Palaquium obovatum (Sapotaceae).
Physical Description of Adult Butterfly : The upperside of the Malay Viscount is a pale greyish ochreous brown, with sub-marginal V-shaped markings on white background. The V-shaped markings are conjoined. The underside is paler, with a faint tinge of violet in a sidelight. In the male, the underside of the hindwing has two rows of small black submarginal separated V-shaped markings whilst these are less distinct, and joined in the female.

Field Observations of Butterfly Behaviour : The Malay Viscount is a forest denizen which is rarely seen outside the nature reserves and forested areas of Singapore. It is relatively common and both sexes are often seen puddling on rotting fruit, carrion or at damp seepages. It flies in the typical Tanaecia or Euthalia fashion, gliding powerfully as it flaps its wings. It is a skittish butterfly, and when disturbed, takes off in a very capable fashion.

Mating pair of Malay Viscount - left-male ; right-female. Note the differences in the underside markings between the two sexes.

Early Stages : The female oviposits on the underside of a mature leaf (usually at the centre) of the host plant. This is quite unlike its close relative, the Horsfield's Baron (Tanaecia iapis puseda), where the female searches for a leaf, and reverses till her abdomen touches the tip of the hostplant leaf, and oviposits on the tip of the leaf. In the Malay Viscount, the female touches the veins of the leaf of the host plant, and oviposits a single egg on the underside of the selected leaf.

Two views of the Malay Viscount egg.
After about four days, the 1st instar caterpillar hatches from the egg, and makes its first meal of the eggshell. The caterpillar crawls towards a younger leaf and proceeds to munch on the leaf edge. The 1st instar caterpillar is yellow-green with simple white-tipped black spines from its body.

1st instar caterpillar

After eating for about 2 days, the caterpillar moults and changes into its 2nd instar. The caterpillar now sports branched spines which radiate horizontally and flat, away from its body. The spines are a pale cream. The caterpillar eats very little, making small cuts along the host plant's leaf edge.

2nd instar caterpillar, sporting its flat branched spines radiating horizontally from its body

At the 3rd instar, the caterpillar's branched spines are now green, with black/white fine hairs giving it the characteristic "Christmas Tree" appearance of many species of this genus and its related genera of Euthalia and Lexias. The caterpillar now has a series of oval greyish purple-centred spots along its back.

A 3rd instar caterpillar showing its purple spots along its back

The 4th instar caterpillar appears quite similar to the 3rd instar, except that it is now much bigger, and the oval purple-centred spots are more distinctly marked and fringed with white with a thin black border. The branched spines are also longer and end with a curved T-shaped hooked spines.

4th instar caterpillar eating along the edge of its host plant leaf

The 5th instar caterpillar has additional whitish spots along its body, whilst the white-fringed purple spots along its back are still prominently displayed. The branched spines are also more complex, and gives the caterpillar an appearance of being a lot larger than it really is. It moves slowly, but eats voraciously - finishing almost a single large leaf in about two days.

A 5th instar caterpillar next to a 3rd instar caterpillar of the Malay Viscount. Note the relative size between the two caterpillars.

Detail of a 5th instar caterpillar, showing its complex branched spines and the row of whitish fringed purple spots along its back.

After about 17 days, the 5th instar caterpillar shrinks in length, and the large purple spots along its back become less distinct. A white saddle stripe appears. Later in the day, the caterpillar turns a yellowish green and stays in this pose until pupation occurs. Pupationg may occur on the top or under surface of a leaf of the host plant. The pre-pupating caterpillar anchors itself securely via its cremaster.

Pre-pupating caterpillar. Compare the markings with the 5th instar caterpillar

The pupa hangs vertially from its cremaster without the need for a girdle or any other support. The light green pupa sports a series of gold-coloured spots which are highly reflective. After about nine days, the pupa turns dark, and the pupa shell becomes transparent the night before eclosion. The wing patterns of the butterfly can be seen clearly through the transparent pupa shell.

Different views of the pupa of the Malay Viscount. Note the gold spots. The wing patterns of the adult butterfly are visible through the transparent pupa shell on the night before eclosion

The Malay Viscount ecloses relatively early in the morning between the hours of 8am and 10am when the sun is warm enough.

A freshly-eclosed female Malay Viscount holding on to its pupa shell before taking off when her wings are properly dried

Female Malay Viscount spreading her wings to sunbathe

A male Malay Viscount feeding on an overripe Ficus fruit along a trail in the nature reserves

Text & Photos by Khew SK

The Flying Tigers of Singapore

Featuring the Five Flying TIGERS of Singapore

Not of the feline variety, but butterflies (what else?!).

Singapore is home to five species of butterflies from the sub-family Danainae which have been given the common name "TIGER". The origin of the common name probably referred to the striped wing patterns and, in a number of species, the orange colour of the wings.

The sub-family Danainae features medium sized to large butterflies which are showy, and tend to fly slowly and gracefully. As they fly from flower to flower in search of nectar, one can appreciate their beauty and colours at close range. There is an explanation for their nonchalance and devil-may-care behaviour, due to the fact that almost all the species in the sub-family have "built-in" immunity to predators. In their early stages as leaf-munching caterpillars, the species of this sub-family feed on lactiferous vines and plants which makes the caterpillars and later on, the adult butterflies, distasteful to birds and other predators.

The very obvious markings and colours of the Danainae species is a purposeful 'advertisement' to predators that they are unpleasant to eat, and to stay away from them. So successful is this display, that several other species of butterflies, which do not have this protection, mimics the colours and patterns of the Danainae to benefit from their immunity to predators.

The five Tiger species found in Singapore are :

• Plain Tiger (Danaus chrysippus chrysippus)
• Common Tiger (Danaus genutia genutia)
• Black Veined Tiger (Danaus melanippus hegesippus)
• Blue Glassy Tiger (Ideopsis vulgaris macrina)
• Dark Glassy Tiger (Parantica agleoides agleiodes)

The Plain Tiger is probably the commonest Danaus species and is found in parks and gardens where its preferred host plant, Calotropis gigantea is cultivated. The Plain Tiger has orange forewings with a broad black apical border bearing a series of white spots. It occurs in two forms where form-chrysippus has its hindwing coloured orange as in the forewings. This form occurs more often in northern Malaysia (Penang, Kedah and Langkawi Islands) and in Singapore.

The white hindwinged form-alcippoides is more common in the rest of Malaysia, but also occurs commonly in Singapore. Generally, this form is the more predominant form of the species in Singapore, outnumbering the orange-hindwinged form-chrysippus by at least 10:1 during a survey of the species in 2004.

Where the host plant is found, one can often find the droppings of of the caterpillars on the large leaves of Calotropis gigantea. It is not unusual to find a large number of the caterpillars on a single plant where the entire plant may defoliated in matter of weeks.

The Common Tiger has the same colouring as the Plain Tiger, except that its wings' veins are strongly marked with black. Sometimes almost as common as the Plain Tiger, the Common Tiger is often found in mangrove areas where its host plant, a lactiferous vine, Raphistemma sp. grows.

As in the case of the Plain Tiger, the Common Tiger occurs in two forms. - the orange hindwinged form-genutia and the white hindwing with orange-tinged border form-intermedius. In Singapore, both forms occur, but again, like the Plain Tiger, the white with orange-tinged border form is the commoner of the two.

The Black Veined Tiger is the least common of the three Danaus species in Singapore. This species is very similar to the Common Tiger and is often mis-identified as such. However, the difference is that the white hindwings do not have an orange tinge as in the form-intermedius of the Common Tiger. The black hindwing border is also much wider than in the Common Tiger. On the offshore island of Pulau Tekong, the Black Veined Tiger is the predominant species and is much more common than the Common Tiger, as compared to the main island of Singapore.

The males of all three Danaus species possess an oval brand enclosing scent scales on the hindwing which appears as a black bordered pouch. The females do not have this feature.

The Blue Glassy Tiger belongs to the genus Ideopsis. It is the only representative of the genus in Singapore. The wings are predominantly a translucent bluish grey, with the veins blackened, giving the butterfly a striped appearance. The Blue Glassy Tiger is common in Singapore, and can be found in gardens, parks and within the nature reserves.

Its lactiferous host plant, Tylophora sp. is a common vine growing in secondary vegetation and particularly in the mangrove areas. The species is likely to have several other alternative host plants.

The Dark Glassy Tiger which, at a glance, appears like the Blue Glassy Tiger, is the only representative of the genus Parantica in Singapore. Its closely related cousin, the Yellow Glassy Tiger (Parantica aspasia aspasia) has not been seen in Singapore for a long time, and feared extinct. The ground colour of the Dark Glassy Tiger appears less bluish in flight, giving a more greyish appearance. It can be distinguished from its lookalike, in that the forewing cell streaks of the Dark Glassy Tiger contain thin longitudinal black lines, whereas there is a diagonal black bar in the Blue Glassy Tiger's forewing cell.

Both the Blue and Dark Glassy Tigers often occur together in the same vicinity and both are common butterflies in Singapore. The males can be separated from the females by the darkened brands at the sub-tornal area of the hindwing.

All the five Tigers are slow flyers and often stop to feed at flowering plants. They are relatively easy subjects to photograph, and are very likely to feature in any enthusiastic butterfly photographer's portfolio of butterfly pictures. All the species are attracted to the flowers of the Indian Heliotrope (Heliotropium indicum) and in particular, the semi-dried leaves and stalks of this plant are particularly attractive to the Tigers.

Text by Khew SK ; Photos by Khew SK, Simon Sng & Wong CM