When the Melastoma Blooms...

When the Melastoma Blooms...
The Singapore Rhododendron and Butterflies

The Singapore Rhododendron (Melastoma malabathricum) is a rather amazing plant. Despite being mistakenly named so, it is neither a Rhododendron, not is it confined to Singapore only. From the plant family Melastomaceae, the Singapore (or sometimes also called Straits) Rhododendron is a common plant that springs up almost anywhere where land is cleared, or along open forest paths. The seeds of this plant are dispersed mainly by birds and mammals that feed on its rather sweet fruits, and the plant appears as commonly in the nature reserves as well as urban parks and gardens.



Though an under-appreciated plant by horticulturists, the Singapore Rhododendron is a favourite with bird watchers and butterfly enthusiasts. This is because the flowers and fruits are targeted by birds, butterflies and small mammals. In particular, the Scarlet Backed Flowerpecker is a regular visitor to fruiting Melastoma bushes.

The Singapore Rhododendron usually grows as a "weed" in untended areas, normally up to a metre high, and if left to grow, can reach heights of up to 3 metres. It is a small shrub, that has tiny scales on its branches and petioles. The leaves are narrow and lanceolate, about 5-10 cm long, usually with 3 prominent veins running from the base.



The flowers are light pink-purple, with elbowed anthers surrounding the style, and are borne in clustered inflorescences. The fruit is interesting, a sort of pod, usually about 1.5 cm long, which is covered in small bumps and topped with a persistent calyx.

The greenish pod splits open halfway and flips over to reveal a fleshy deep purple structure studded with numerous (about a thousand) tiny seeds, and is usually 5-sectioned. The fruits are berry-like and break open irregularly. The seeds stain the mouth when eaten, and is sweet and slightly astringent.


A Purple Duke extends its proboscis deep into the fruit of the Singapore Rhododendron. Note the white seeds covering the fruit


The Singapore Rhododendron and Butterflies

Whilst butterflies are occasionally observed to feed on the nectar of the purple-pink flowers, the primary pollinators appear to be bees and wasps.

A small bee approaching the flower of the Singapore Rhododendron for nectar

It is the ripening fruits that are irrestible to butterflies, and when a bush has many such ripened fruits, there will often be swarming with butterflies of the Nymphalidae and Lycaenidae families.

The Colonel (Pandita sinope sinope), a Tawny Palmfly (Elymnias panthera panthera) and a Grey Pansy (Junonia atlites atlites) feed on the Singapore Rhododendron fruits

From many such encounters, ButterflyCircle members have observed that many butterflies that feed on the sweet ripened fruits can sometimes be so intoxicated as to be able to be picked off the fruits with our fingers! They can stay still and continue feeding for long periods of time, allowing the photographer to shoot many shots of a species that is usually skittish and difficult to approach.

A Commander (Moduza procris milonia), a Common Palmfly (Elymnias hypermnestra agina) and a Grey Sailer (Neptis leucoporos cresina) feeding on the fruits of the Singapore Rhododendron

Interestingly, butterflies of the Papilionidae, Pieridae, Riodinidae and Hesperiidae families seem to have less preference for the fruits of the Singapore Rhododendron.

A female Malay Baron (Euthalia monina monina) perched on the fruits of the Singapore Rhododendron

For the butterflies that feed on the ripened fruits, they often have to share the sweet bounty with ants, bees and wasps. The latter two feeders tend to also scare the butterflies away as they barge in onto the fruits.

A Yellow-vented hornet (Vespa analis) helps itself to the fruits of the Singapore Rhododendron

After having their fill of the fruit juices, many of the Nymphalidae, particularly from the genera Tanaecia and Euthalia, will rest in nearby shady spots or sunbathe with their wings opened on sunlit leaves. This gives further opportunities to observe and photograph the butterflies when they are slightly more lethargic than usual.

An Acacia Blue (Surendra vivarna amisena) feeds on the ripened fruit of the Singapore Rhododendron

The ripened fruits tend to be viable to attract butterflies for quite some time - often up to a week or more, as the sugary substance that the butterflies like to feed on appear to regenerate itself during the humidity of the night or after a short shower. During the daytime, the sun dries up the fruits, where it becomes less attractive to the butterflies. We've observed butterflies probing their proboscis deep into the edges of the fruit shell, where the sugars are probably still liquid enough to be imbibed by the butterflies.


A female Purple Duke (Eulaceura osteria kumana) feeds on the ripened fruit of the Singapore Rhododendron next to a goblet-shaped fruit that has yet to ripen

Besides providing a food source for the adult butterflies, the Singapore Rhododendron is also the known host plant to the Horsfield's Baron (Tanaecia iapis puseda) and two Lycaenids - the Long Banded Silverline (Spindasis lohita senama) and Semanga superba deliciosa. The caterpillars of all three species feed on the leaves and shoots of the plant.

A female Horsfield's Baron (Tanaecia iapis puseda) oviposits on the leaf tip of the Singapore Rhododendron, and the 5th instar caterpillar of the Horsfield's Baron


Two pretty Lycaenids - The Long Banded Silverline (Spindasis lohita senama) and Semanga superba deliciosa whose caterpillars depend on the Singapore Rhododendron as one of their caterpillar host plants

And so the humble "weed", the Singapore Rhododendron is a very versatile plant, critical to the survival of many butterfly species in Singapore and South-East Asia, by providing nectar, sugars from the fruits and leaves for the caterpillars.



Text by Khew SK : Photos by Khew SK

Life History of the Glistening Caerulean

Life History of the Glistening Caerulean (Jamides elpis pseudelpis)

Butterfly Biodata:
Genus: Jamides Hübner , 1819
Species: elpis Godart, 1824
Sub-species: pseudelpis Butler, 1879
Wingspan of Adult Butterfly: 30mm
Caterpillar Local Host Plants: Saraca cauliflora (Leguminosae, common name: Yellow Saraca); Lepisanthes amoena (Family: Sapindaceae).


A Glistening Caerulean sampling a water droplet on a leaf bud.

Physical Description of Adult Butterfly:
Above, the male is pale shining sky blue, with thread-thin forewing border and absence of submarginal markings on the hindwing. The female is pale blue with forewing border ending at mid costa. Beneath, the narrow striae are white and straight, or nearly so. Being a member of the elpis subgroup (of the celeno group), the Glistening Caerulean also has the post-discal band on the forewing underside completely dislocated at vein 3. On the hindwing, the second white stria from the base in space 7 is about mid-way between the second and third striae from the base in the cell. Each hindwing features a black-centred orange-crowned tornal spot, rather large submarginal orange markings along veins 1b and 4, and a white-tipped filamentous tail at the end of vein 2.


A male Glistening Caerulean giving us a full view of its glistening blue upperside.


A Glistening Caerulean perching on a leaf of the Yellow Saraca.

Field Observations of Butterfly Behaviour:
This species is rarely encountered in Singapore. It is re-discovered in the early part of this year in an urban garden where a small colony was found to be breeding on the two host plants present. At this site, the males were observed to be flying around in sunny weather, and puddling on wet ground. A number of females were also with sighted carrying out their oviposition routines on flower buds of both host plants.


A Glistening Caerulean perching on a broken twig.

Early Stages:

The 1st local host plant, Lepisanthes amoena (Kayu Matahari) is a small to medium-sized tree with imparipinnate (pinnate with a terminal leaflet) leaves. Leaf-like pseudo-stipules are present. The whitish flower buds are globular and occur in terminal panicles. Fruits are tri-lobular and turn reddish brown when ripened. Early stages of the Glistening Caerulean feed on flower buds and flowers of this plant.


Host plant: Lepisanthes amoena: Flower buds (left); Fruits (right).



A mother Glistening Caerulean laying her eggs on flower buds of Lepisanthes amoena.

The 2nd local host plant, Saraca cauliflora (Yellow Saraca) is a small to medium-sized tree with pinnate leaves in 4-6 pairs. The flowers are orange-yellow in large clusters on trunk or branches. Early stages of the Glistening Caerulean feed on flowers parts of this host plant.


Yellow Saraca: cauliflorous flowers (left); pinnate leaves and seed pod (right).


A mother Glistening Caerulean laying her eggs within a cluster of Yellow Saraca flowers.

Eggs of Glistening Caerulean are laid singly on flower buds or flower parts of the host plant. The small pale green egg is disc-like and about 0.4-0.5mm in diameter. Its surface is covered with a reticulated pattern of intersecting ridges.


Eggs of the Glistening Caerulean laid on flower parts. Left: on Lepisanthes amoena;
Right: on Yellow Saraca.

The egg takes 2-3 days to hatch. The young caterpillar emerges after nibbling away sufficiently large portion of the egg shell. Measured at a length of about 0.8-0.9mm, its pale yellow body is cylindrical in shape, sporting long fine setae (hairs) and a dark head capsule. There is also a dark prothoracic shield and an anal plate.


Bottom: A newly hatched caterpillar of the Glistening Caerulean, length: 0.8-0.9mm.
Top: A late 1st instar caterpillar, 1.9mm.

The newly hatched grazes on the surface of flower petals or bores into a flower bud for the goodies within. After about 2 days of growth and reaching a length of about 2.5mm, the caterpillar moults to the next instar.


Boring into flower parts. Left: a newly hatched on Yellow Saraca flower.
Right: a 2nd instar caterpillar on a flower bud of Lepisanthes amoena.

The 2nd instar caterpillar has numerous short setae with dark base and this gives the pale yellow body surface a heavily dotted appearance. From this instar onwards, the small diamond-shaped prothoracic shield takes on a pitch black coloration. This instar lasts about 2 days with the body length reaches up to 4.5mm.


2nd instar caterpillars, late in this stage, length: 4mm.

The 3rd instar caterpillar resembles the 2nd instar caterpillar with body color pale to dark yellow. Both the dorsal nectary organ (on the 7th abdominal segment) and tentacular organs (on the 8th abdominal segment) are barely discernible. The 3rd instar takes 2.0 days to complete with the body length reaching about 7.0mm.


3rd instar caterpillars. Top: newly moulted, 4.3mm. Bottom: 5.5mm.

Still covered with numerous fine setae on the body surface, the 4th (and final) instar caterpillar has taken on a darker shade of yellowish brown. The dorsal nectary organ is now prominently marked with an encircling dark brown patch. Another noticeable change is in the diamond shaped prothoracic shield which now has a vertical split.


4th instar caterpillar feeding on Yellow Saraca flowers.
Top: early in this stage, length: 7.5mm. Bottom: late in this stage, length: 12mm.

After 4-5 days of growth and reaching a maximum length of around 11-12mm in the final instar, the body of the caterpillar gradually shrinks, and finally takes on a dark pinkish to reddish brown coloration. All bred specimens chose to enter their pre-pupatory phase in tight pockets of space within leaf debris. At the chosen spot, the caterpillar readies itself for pupation by spinning a silk girdle and a silk pad. The caterpillar secures itself to the silk pad via claspers on its posterior end.

Two views of an immobile pre-pupatory larva of the Glistening Caerulean.


The girdled down pre-pupa still has the ability to evert its tentacular organs, indicating that
ant-larva association does continue into the pre-pupal stage.

Pupation takes place after one day of the pre-pupal stage. The pupa has the typical lycaenid shape. It is pale yellow to beige in base color with a number brown and black specks. of various sizes. The pupa has a length of about 8-9mm.


Two views of a pupa of the Glistening Caerulean, length: 9mm

Eclosion takes place after 6 days in the pupal stage. The mature pupa gradually darkens in colour the day before. Bluish patches on forewing uppersides become clearly visible in the wing pads of the mature pupa. The extent of these bluish patches reveals the gender of the soon-to-emerge adult.


Two views of a mature pupa of a female Glistening Caerulean.


A newly eclosed male Glistening Caerulean

References:

• 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 Bobby Mun, Sunny Chir, Khew SK and Horace Tan

Observation Notes on the variability of the female Jacintha Eggfly

Observation Notes on the variability of the female Jacintha Eggfly

A typical Jacintha Eggfly perches on a leaf in an urban hill park

The Great Eggfly (Hypolimnas bolina) has a number of subspecies according to various sources. A quick online research shows about seven subspecies. Thus far, only two of these subspecies occur in Singapore - ssp bolina and ssp jacintha.

A female Jacintha Eggfly oviposits on its host plant, Asystasia gangetica

Whilst subspecies bolina is of particular interest because of its polymorphism of which the individual specimens are highly variable, and at least four principal forms are recorded, which are connected by intermediates. It is so highly variable, that C&P4 records that "it is difficult to find two exactly matching examples"!

A Jacintha Eggfly puddling

Leaving subspecies bolina aside for the moment, this article focuses on the subspecies jacintha or what ButterflyCircle members refer to as the Jacintha Eggfly. It is interesting to note that C&P4 and Fleming, who both published books spanning the last century, records ssp jacintha as "increasingly rare" towards the end of the 19th century, and then almost disappearing altogether. In fact, Fleming's book lists ssp jacintha as "very rare". However, in the 1970's this subspecies began to re-establish itself in the Malay Peninsula "where it interbreeds with ssp bolina giving rise to adults showing a wide degree of intergradation, so that it is often not possible to assign specimens to one subspecies or the other".

A typical f-incommoda female Jacintha Eggfly

Observations made in the late 90's to the early part of the 21st century in Singapore indicate that the ssp bolina is again on the decline, and now being replaced by the more common ssp jacintha. The more distinctive females of ssp bolina with its typical orange forewing patch is now rare, and more often seen only on Pulau Ubin than anywhere else in Singapore, where it was previously common. The ssp jacintha is the more commonly occuring subspecies today.

A Jacintha Eggfly perches on a branch. Note the broad submarginal markings on the hindwing

From contemporary literature, various authors have recorded the female ssp jacintha as having only two forms. These are female f-jacintha and f-incommoda.

A typical male Jacintha Eggfly. The males are almost indistinguishable from the males of the subspecies bolina males

Males are rather similar to the ssp bolina and often indistinguishable. The typical female f-jacintha is apparently the rarer of the two forms, where the female is almost totally brownish grey on the uppersides with the usual white spots on both wings. The f-incommoda with varying blue patches on the forewings and hindwings and light blue subapical spots on the forewings, is more common. Even so, this form is very variable, with the extent of the blue patches varying from very little to significant.

A series of female Jacintha Eggfly, showing the variation in the blue markings on the forewings above as well as the subapical blue spots on the forewing. In the first specimen, the blue patches extend to the hindwings as well.

Of late, another possible form has emerged. This is a female with predominantly brown wings above, with the typical white spots of f-incommoda but with reduced blue tinge on the forewing costal margin. But of note would be the significant large white patches on the hindwing above. This "form" has not been previously observed in Singapore, although this site shows some similar individuals which could suggest that this "form" exists elsewhere in Asia. First seen in at least 3 females bred in captivity, a free-ranging female of this "form" was eventually photographed by ButterflyCircle member Federick Ho in a patch of wasteland to the north-east of Singapore island - suggesting that this "form" may occur in the wild as well.

Shots of the previously unrecorded form of the female Jacintha Eggfly. Note the extensive white patch on the hindwing, which is absent in the two known female forms of the Jacintha Eggfly in Malaysia and Singapore.

In late 2009, I managed to capture a voucher specimen of this new "form" at a site in Punggol, which has been, unfortunately cleared for redevelopment now. The female was found in the vicinity of its host plant Asystasia gangetica a common roadside weed.

A wild-captured voucher specimen of the new form of the Jacintha Eggfly, showing upperside (left half) and underside (right half) of the wings

It will be necessary to document the occurrence of possible new forms of this subspecies of the Eggfly, and indeed, if possible to conduct further breeding observations to see if the ssp bolina and ssp jacintha are two subspecies of the Great Eggfly or just a single subspecies with many different forms!

Until then, if you have photos of the Jacintha Eggfly, particularly showing the uppersides of the female butterfly, please send them to ButterflyCircle at hexaglider@yahoo.com for records.

Text by Khew SK ; Photos by Federick Ho, Khew SK, Loke PF, Sum CM & Terry Ong

References :

• Bolina World (A Japanese Website)
• The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
• Butterflies of West Malaysia and Singapore, W. A. Fleming, 2nd Edition, Longman Press

Guest Lecture by Assoc Prof Yen Shen Horn

Guest Lecture by Assoc Prof Yen Shen Horn

Biological Mimicry of Moths, Spiders & Fishes : Opportunities, Challenges and Perspectives Based on Asian Fauna

On Saturday, 7 Nov 09, four ButterflyCircle members were invited to a guest lecture by Assoc Prof Yen Shen Horn of the Department of Biological Sciences, National Sun Yat Sen University in Kaohsiung, Taiwan. The invitation to this very interesting talk was courtesy of Dr Leong Tzi Ming of the National Parks Board. Dr Leong, an avid lepidopterist, has published many papers on the on-line version of the Raffles Bulletin, Nature in Singapore.

Held at the exhibition area of the Raffles Museum of Biodiversity in a rather informal setting, A/Prof Yen held the small audience engaged in a very informative talk that lasted for over one and a half hours.

A/P Yen first shared with the audience what he and his department are currently focusing, in terms of research projects. Whilst many of the topics are highly academic and research type, it also expanded my outlook towards the depth of research that many experts like A/P Yen was doing.

A slide showing the multiple origins of Papilio paris in Taiwan

He also discussed the hybridization zone and climatic features affecting Hypolimnas bolina. An intriguing point that he made about H. bolina also corresponded with what I'd always also wondered about this species - that the subspecies that occur in Singapore and Malaysia could well be different forms as well. Over the past two decades, we've found the return of the subspecies jacintha and appears to have overrun the more common subspecies bolina in recent years. In the mid 90's the latter subspecies was a lot more common, but now appears to be very much rarer, with the subspecies jacintha making more frequent appearances.

A/P Yen then went on to discuss the theory of mimicry as expounded by the early researchers, Henry Walter Bates (1825-1892) and Dr Fritz Muller (1821 - 1897), and also the theories of Edward Bagnall Poulton, who offered his own theories about mimicry during the same era.

The discussion covered aposematism and what A/P Yen mentioned about the general reference to warning colouration in public talks is quite true - that an organism that is inherently colourful or with a flashy display of colours, is not necessarily exhibiting the fact that it is poisonous.

Also very interesting, were the studies that A/P and his co-researchers did of the Jumping Spiders and their preference of preys in a controlled environment.

One of the slides also depicted the many day-flying moths that ButterflyCircle members often encounter when out in the field. These moths, largely from the family Chalcosiinae, are often the models for other Lepidoptera mimic for protection against predators. It is also interesting to see that many butterflies (and moths) look very much like many of the moth species from this family. Many good examples of both Batesian and Mullerian mimicry strategies are found amongst these species.

A/P Yen also shared some digital resources of Lepidoptera in Taiwan. A few of the URLs are shown in the slide below. There are also many other projects and resources indicated in A/P Yen's CV. A particularly interesting one is the database of Global Butterfly Names.

The talk ended with a lot of thought-provoking issues on Lepidoptera research and questions that remain unanswered in this very fascinating subject. As ButterflyCircle comprise of mainly amateurs and hobbyists, though with more than a fleeting interest in butterflies, there is definitely a lot more ground to cover , and mysteries to unravel in the world of our Flying Jewels.

A/P Yen, Dr Leong TM and the BC members then visited the Raffles Museum of Biodiversity Research's lepidoptera collection and spent some time sharing anecdotes and experiences about the butterflies and moths in the collection.

Text and Photos by Khew SK. Talk Poster courtesy of A/Prof Yen Shen Horn

Acknowledgments :

• Associate Professor Yen Shen Horn, National Sun Yat Sen University, Taiwan
• Dr Leong Tzi Ming, Conservation Division/National Parks Board
• Kelvin Lim, Curator, Raffles Museum of Biodiversity

References :

• Wikipedia Online

Life History of the Large Four-Line Blue

Life History of the Large Four-Line Blue (Nacaduba pactolus odon)

Butterfly Biodata:
Genus: Nacaduba Moore, 1881
Species: pactolus C. Felder, 1860
Subspecies: odon Fruhstorfer, 1916
Wingspan of Adult Butterfly: 32mm
Caterpillar Local Host Plants: Entada spiralis (Fabaceae)


A Large Four-Line Blue perching on a small branch in the nature reserve.

Physical Description of Adult Butterfly:

The Large Four-Line Blue belongs to the pavana sub-group (the Four-Line Blues) in the genus Nacaduba, thus it possesses the shared characteristics of lacking a basal pair of lines in the underside forewing cell. Above, the male is purplish blue with marginal black borders of about 1.0mm thick. The female is pale blue with distal portions almost whitish, and has broad black borders of about 3-4mm thick. Beneath, both sexes are greyish brown with a slight silky lustre and with the space between the post-discal straie being unicolourous and of the ground colour. The underside stripes are broader and more diffuse than the other members, with the exception of N. angusta, of the pavana sub-group. On each hindwing, there is an mid-sized orange-crowned tornal spot lightly speckled with bluish-green metalic scaling. Both sexes have a filamentous white-tipped tail at the end of vein 2 of the hindwing.

The upperside of a female Large Four-Line Blue.

Field Observations of Butterfly Behaviour:

Although there were a mere handful of sightings of individuals during one survey and 2-3 outings in the past few years, the re-discovery of this species was only recently nailed with an ID confirmation provided by Prof Konrad Fiedler. This species is uncommon in Singapore but adults have been sighted in multiple locations such as the Central Catchment Nature Reserve, Southern Ridges, western wasteland and an offshore island. The adult has an erratic but rapid flight, and typically makes its appearance in sunny weather. Encounters usually take place in sunlit spots with the adult sunbathing or flitting from perch to perch in the vicinity of its host plant.

Early Stages:

The only known local host plant, Entada spiralis, is a woody climber with bipinnate leaves, usually with 4 pairs in a pinna. This tree-topping vine can be found in the Central Catchment Nature Reserve and Southern Ridges. The early instars of the Large Four-Line Blue feed on soft tissues of the host plant such as young leaves, young stems, tendrils, and flower buds. Across its range of distribution, N. pactolus has been found to use only one plant genus (Entada) as larval host, thus it is a stenoligophagous species.

Young shoots of Entada spiralis.


Oviposition by Large Four-Line Blue females. Left: on the underside of a young leaf. Right: on flower buds.


A mother Large Four-Line Blue laying an egg on a young shoot of E. spiralis.

Eggs are laid on young shoots, flower buds and young leaves (underside) of the host plant. Each egg is pale yellowish green, circular and has a depressed micropylar area. The surface is criss-crossed with a network of ridges. Each egg has a diameter of about 0.4mm.

Two eggs of the Large Four-Line Blue. Diameter: 0.4-0.5mm.

It takes about 2 days for the egg to hatch. The young caterpillar consumes part of the egg shell to emerge. With a length of about 0.7-0.8mm, it has a pale yellowish green body with long setae (hairs) occurring dorsally and sub-spiracularly. The caterpillar assumes the typical woodlouse body shape as it grows. Both the diamond-shaped pro-thoracic shield and the anal plate are pale green.

1st instar caterpillar, early in this stage, length: 1mm.

The first instar lasts for 2 days and the body length reaches about 1.5mm before the moult to the 2nd instar. The long dorsal setae are absent in the 2nd instar caterpillar. The body is yellowish green and has coarser texture on its surface. The dorsum of the thorax is slightly depressed. The 2nd instar also lasts for 2 days and the caterpillar grows to a length of about 3.5mm.

2nd instar caterpillars, length: 2mm.

The 3rd instar caterpillar is still yellowish green but with a stronger emphasis in green. Faint markings in much paler yellow appear on both sides of the dorsal line. The body is also densely covered with short brown or transparent setae. Both dorsal nectary organ and tentacular organs are not unmarked and are barely distinguishable. The prothoracic shield is white with a slight greenish tinge.

3rd instar caterpillars, late in this stage, length: 6.5-7mm

After 3 days in the 3rd instar with the body length reaching a maximum about 7-8mm, the caterpillar moults to its final instar. The 4th instar caterpillar initially resembles the 3rd instar caterpillar closely. As the body grows larger in size, its colour assumes a much darker shade of green.

Two views of a 4th instar caterpillar, length: 13mm.


4th instar caterpillar. Left: Prothoracic shield; Right: Dorsal nectary organ (DNO) and
tentacular organs (TO).

The 4th instar lasts for 4 days and the body grows up to a length of about 13-14mm. On the last day of this stage, the caterpillar ceases food intake and its body shrinks in length. Once a pupation site is selected, the pre-pupatory caterpillar prepares for pupation by spinning silk threads to form a silk pad on the substrate. It then stations itself with a silk girdle across its thorax and with its rear end attached to the silk pad.

Two views of a pre-pupa of the Large Four-Line Blue

The next day, after 11-12 days of larval growth, pupation finally takes place. The pupa has the typical lycaenid shape, and is covered with short brown setae. Ground colour is pale brown, and mottled with dark brown spots of various sizes and shapes. Length of pupae: 9-10mm.

Two views of a fresh pupa of the Large Four-Line Blue

Five days later, the maturing pupa becomes increasingly darkened in the head, thorax and the wing pads. The blue patches on the forewing upperside are now noticeable through the pupal skin. The next day the adult butterfly emerges from the mature pupa.

Two views of a mature female pupa showing the markings on the forewing upperside in the wing pad.


A newly eclosed Large Four-Line Blue resting on its pupal case

References:

• The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
• Butterflies of Thailand, Pisuth Ek-Amnuay, 1st Edition, 2006
• Notes on Host Association and Immature Biology of Nacaduba pactolus hainani, Y-F Hsu et al, BioFormosa, 34 (2), 2004, pp.61-65.
  

Text by Horace Tan, Photos by Sunny Chir and Horace Tan

Butterfly of the Month - November 2009

Butterfly of the Month - November 2009
The Striped Albatross (Appias libythea olferna)

A mating pair of Striped Albatross (Appias libythea olferna)

Time flies! And the eleventh month of 2009 is now upon us. November heralds the beginning of a generally wet season for SouthEast Asian countries as the start of the North East monsoon months commence in the region. Usually rainy with strong winds, the final few months of the year is usually 'low season' for butterflies.

A female Striped Albatross on Bidens sp one of its favourite nectar flowers

However, due to the north-easterly winds that blow from up north, it's also the time of the year where ButterflyCircle members have observed "immigrants" that are stowaways on the winds that carry them from Malaysia. So in between the rainy days when there are the occasional days of sunshine, there could be interesting finds to celebrate!

A pair of Striped Albatross shares nectar from a flower of Bidens sp.

This month, we feature the humble and common Striped Albatross (Appias libythea olferna). This species, described as rare in the 1960's and 70's, originates from India, Sri Lanka and Burma where it is common. However, it became progressively more common in Malaysia and Singapore in later part of the 20th century.

A theory was that as land was cleared and roads opened, its host plant, Cleome rutidosperma, a weed of sorts, became more and more abundant. Usually, in a patch of cleared urban land, this is one of the first weeds to colonise the bare earth. This plant, also often called Wild Cat's Whiskers, is a caterpillar host plant to two other Pieridae species as well, besides the Striped Albatross. With the availability of the host plant, the species was able to spread easily, and is today a common urban butterfly - in Malaysia and Singapore.

Upperside of a male Striped Albatross

The Striped Albatross is a species that demonstrates sexual dimorphism. The male is white above, with a dentate black border. The undersides have dark dusted veins, and the hindwing basal area lightly marked with yellow. Females are heavily dusted with greyish yellow on both the upper and undersides, and the basal area of the hindwing below is generously marked with yellow.

Both sexes have semi-transparent compound eyes and rather hairy in the palpi area. The antennae are banded with black and white and prominently clubbed. All six legs are fully developed.

The butterfly is a fast and erratic flyer, the male more so than the female, and are very skittish. They are often best photographed when feeding on wildflowers, although they are still sensitive to movement and will take off at the slightest hint of danger. Photographers have to move very stealthily in order to get a good shot of this species.

A male Striped Albatross puddling at a footpath in an urban park

Males are occasionally encountered puddling at sandy stream banks and paths, usually tainted with animal urine or decomposing organic matter. Both sexes are more frequently encountered in urban parks and gardens and less frequently in the forested nature areas in Singapore. They prefer to fly in open plains on hot sunny days.

Text by Khew SK : Photos by Benedict Tay, Federick Ho, Henry Koh, Khew SK, Sum CM, Sunny Chir and Tan BJ

Of Saws and Teeth

Of Saws and Teeth
The Sawtooth Butterflies



I've always wondered about the English Common names of the two species from the genus Prioneris. These large and robust butterflies found in Malaysia, belong to the family Pieridae. The two species, Prioneris philonome themana is known as the RedSpot Sawtooth whilst its close relative Prioneris thestylis malaccana is called the Spotted Sawtooth.

A RedSpot Sawtooth puddling at Endau Rompin Nature Reserve, Malaysia

Both the species are large butterflies and resemble the Appias (Albatrosses) and the Delias (Jezebels), to which they are relatively related. However, the Sawtooths are powerful flyers and are fast on the wing.

Another RedSpot Sawtooth puddling on damp ground

Both species are white above with the veins blackened in the outer margin areas The RedSpot Sawtooth has the hindwing basal two-thirds yellow, with a small red basal patch. The veins are prominently darkened. Its cousin, the Spotted Sawtooth is similar but has the entire hindwing yellow.

A RedSpot Sawtooth and a Blue Jay puddling on a sandy river bank

The RedSpot Sawtooth is the more common of the two species, and is found in the forested areas of Malaysia, often puddling with other Pierids and Papilionids. The Spotted Sawtooth prefers higher elevations but also has the same propensity for puddling at damp sandy stream banks tainted with animal urine and other decomposing organic matter.

A Spotted Sawtooth puddling next to a Chocolate Albatross

Coming back to the common name of "Sawtooth", it only dawned on me when I enlarged a shot that I took of the Spotted Sawtooth during post-processing, and I noticed the costa (or the leading edge) of the forewing. In the highly magnified view, one can observe that the wing edge is actually serrated with a series of sharp 'teeth' like the blade of a saw!

A Spotted Sawtooth puddling on tainted sand at Fraser's Hill

So now we may have stumbled upon one of the possible reasons behind why the early English collectors christened these two butterflies with the name of "Sawtooth". Click on the photo below to get a larger view of the serrated forewing of the butterfly's wing and you can see the details of the saw-like edge.

Text by Khew SK : Photos by Khew SK ; LC Goh & Sunny Chir