22 September 2012

Life History of the Perak Lascar

Life History of the Perak Lascar (Pantoporia paraka paraka)



Butterfly Biodata:
Genus: Pantoporia
Hübner, 1819
Species: paraka Butler, 1879
Subspecies: paraka
Butler, 1879
Wingspan of Adult Butterfly: 35-45mm
Caterpillar Local Host Plants:
Dalbergia candenatensis (Leguminosae), Dalbergia rostrata (Leguminosae), Cnestis palala (Connaraceae).




Physical Description of Adult Butterfly:
Above, the wings are dark brown to black with orange markings. On the forewing, there is a broad orange cell streak with two small indentations.  There are two orange submarginal lines on the forewing, one or both of which bends at  space 3.  The hindwing has a subbasal streak passing through base of cell, and a basal streak passing along costa. The dorsum of the thorax has a small yellowish green band aligned with the forewing cell streaks. Underneath, the wings have pale orange markings corresponding to those on the upperside, but generally larger, more diffuse  and edged in brown to black along some edges..These markings are set against a background in a shade of yellowish orange.



Field Observations of Butterfly Behaviour:  
This species is moderately common in Singapore.  It is more frequently found in back mangrove habitats (Sungei Buloh Wetland Reserve, Kranji nature trail, Pulau Ubin and Pulau Semakau) where its host plant,  Dalbergia candenatensis, thrives. The species can also be sighted, though less frequently, along forest trails in the nature reserve where its other host plant, Dalbergia rostrata,  is growing in small clusters on trail sides. The adults are weak flyers but are rather alert and skittish, and would quickly ascend to the tree top when alarmed. The adults have been sighted visiting flowers and puddling on wet ground, and would typically open their wings fully when perching.



Early Stages:
Of the three recorded local host plants for the Perak Lascar, two are Dalbergia species which are both relatively common in back mangrove habitats and in parts of the  nature reserve respectively. The third host plant, Cnestis palala (Connaraceae) which is relatively  rare in the nature reserve,  is also utilized by the immature stages of the Burmese Lascar.  

Local host plant #1: Dalbergia candenatensis.

Local host plant #2: Dalbergia rostrata.

Local host plant #3: Cnestis palala.

The caterpillars of the Perak Lascar feed on the young to middle-aged leaves of its host plants.  They typically feed in the open on the leaf surface, and rest on the midrib between feeds. The lamina of each leaf is usually eaten from the tip, leaving the midrib uneaten. But unlike the Athyma spp., there is no attempt to construct frass chain or frass barrier.  As in the case of Lasippa spp., the caterpillar of the Perak  Lascar in all instars has the habit of cutting rachis and petiole of the leaf it resides on and using silk threads to attach pieces of cut lamina to the exposed midrib. Its diet consists mostly of the brown and withered leaf lamina created in this process.

An early instar Perak Lascar caterpillar found on a leaf of Dalbergia rostrata in the nature reserve.

An early instar Perak Lascar caterpillar found on a leaf of Dalbergia candenatensis in Kranji nature trail.

The eggs of the Perak Lascar are laid singly at the tip of a leaf  or a budding young shoot of the host plant. The ovipositing female shares a common ovipositing routine adopted by a good number of  Nymphalidae species: After landing on a leaf and finding it suitable, the female reverses along the leaf surface, typically along the midrib, until its abdomen tip reaches the leaf tip where an egg is then deposited.

A mother Perak Lascar laying an egg at the leaf tip of a young leaf of Dalbergia rostrata.

Two views of an egg laid at a leaf tip. Diameter: 0.9mm.

The eggs are somewhat globular in shape, with surface marked with hexagonal pits and bearing spines at pit corners, giving them the appearance of minute sea-urchins. The micropylar sits atop. Freshly laid eggs are green in colour, but turning yellowish with rosy red patches when maturing. Each egg has a diameter of about 0.9mm. The egg takes about  3 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 length of about 2mm. It has a cylindrical pale greyish brown  body covered with many small tubercles and short setae. Four pairs of subdoral tubercles, found on the 2nd,  3rd thoraic segments and 2nd, 8th abdomnal segments,  are somewhat larger than the rest. The head capsule is similarly coloured but in a darker shade of brown.

Two views of a mature egg.

Two views of  a early 1st instar caterpillar, hours after it emerged from its egg., length: 2.2mm.

As the caterpillar grows, the body turns increasingly darker. The four pairs of subdorsal tubercles becomes more prominent. After reaching about 4.0mm in 2 days, the caterpillar moults to the 2nd instar.

Two views of a 1st instar caterpillar, late in this stage, length: 4mm.

The body color of the 2nd instar caterpillar is yellowish brown to reddish brown with a series of lateral oblique and inconspicuous streaks. Besides tiny tubercles covering most of its body surface, the 4 subdorsal pairs of tubercles have become longer and more spine-like with short protuberances. Furthermore, each of the two thoracic pairs of spines appear to  be connected with a slightly raised ridge between the two spines on each side. White strips are featured at the base of 8th and 9th abdominal segments. The head capsule is dark brown and dotted with a number of pale yellowish brown conical tubercles. This instar lasts about 3 days with the body length reaching about 5.5-6mm.

Two views of a 2nd instar caterpillar , length: 5.2mm.

The 3rd instar caterpillar has similar body markings as the 2nd instar  but with all  4 paris of subdorsal spines longer proportinately, and ridge connection in the two thoracic pairs more evident. A large saddle becomes apparent with a curved and tapering boundary taking shape, stretching from the base of the 2nd abdominal segment to a spot on the dorsum  of the 8th abdomnal segment between the two subdorsal spines.  This instar takes about 6-8 days to complete with body length reaching about 8-9mm.

Two views of a 3rd instar caterpillar, early in this stage, length: 6.5mm

Two views of a 3rd instar caterpillar, length: 9mm

The 4th instar caterpillar resembles the 3rd instar caterpillar closely. The oblique lateral brown streaks gain greater prominence with an increase in its shade of brown. A black lateral patch now appears  on the 6th abdominal segment, right on the boundary line of the saddle marking. The subdorsal pair of spines on the 8th abdominal segment are now the longest of all the subdoral spines, and are backward pointing as in the case for the pair on the 2nd abdominal segment.  This instar lasts about 8-9 days with the body length reaching about 12-13mm.

Two views of a newly moulted 4th instar caterpillar, length: 9.5mm.

Two views of a 4th instar caterpillar, late in this stage,dormant prior to its moult.

A 4th instar caterpillar found on its resident leaf in a back mangrove habitat.

Except from the proportionately increase in the length/size of the body and head capsule, the 5th instar caterpillar is little changed from the 4th instar in all body markings and features.


Two views of a newly moulted 5th instar caterpillar.


Two views of a 5th instar caterpillar feeding on withered leaf lamina, late in this stage, length: 17mm.

A 5th instar caterpillar found on a leaf in the field. The right panel contains a close-up view.

The duration of the 5th instar is rather variable, ranging from 10 days to 18 days in various bred specimens. The maximum body length is just as variable, with some only reach up only 17mm  and the longest ones up to 21mm.  On the last day, the color of the body decolorises slightly for some specimens, and none at all in others.  Typically, the fully grown caterpillar ceases feeding and stays dormant for a while. Then it proceeds to the tip of the midrib of a  eaten leaf, and spins a silk pad right at the tip. The caterpillar then turns around and attaches its claspers to the silk pad. From this head-up position, it  then gradually lets loose of its foot grip and in one short instant drops down to assume the hanging pre-pupatory posture. This particular `head-up drop' procedure is only adopted by a handful of Nymphalidae species.


A Perak Lascar caterpillar going through the chores of becoming a hanging pre-pupa.

Two views of a pre-pupa of the Perak Lascar.

Pupation takes place about 0.5 to a day later. The pupa suspends itself via a cremastral attachment to the silk pad at the leaf tip. It is almost entirely dark to rusty brown in color, with the ventral side of the head region and leading edge of the wing cases in a lighter shade of brown. The abdominal segments are  bent and tapering to the thin  and narrow cremaster at its posterior end. The wing cases are rather large and broaden laterally. The dorsum of the thorax is angular and is adorned with a number of silvery spots. The head is bluntly cleft at its front edge with small pointed lateral vertices. Length of pupae: 11-12mm.

Three views of a pupa of the Perak Lascar.

A pupa of the Perak Lascar found in the field.

After about 5 days of development, the pupal turns dark as the development within the pupal case comes to an end. The orange spots and streak on the forewing upperside also become discernible. The following day, the adult butterfly emerges from the pupal case.

Three views of a mature pupa. Orange markings on the forewings are now visible.


A Perak Lascar caterpillar emerges from its pupal case.


A newly eclosed Perak Lascar hanging on to its pupal case.


Another newly eclosed Perak Lascar hanging on to its pupal case.

References:

  • [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, The Malayan Nature Society.
  • A Field Guide to the Butterflies of Singapore, Khew S K, Ink on Paper Comm. Pte. Ltd., 2010. 
  • Butterflies of Thailand, Pisuth EK-Amnuay, 1st Edition, 2006.
Text by Horace Tan, Photos by Benedict Tay,  Khew SK and Horace Tan

20 September 2012

Random Gallery - Gram Blue

Random Butterfly Gallery 
The Gram Blue (Euchrysops cnejus cnejus)



An additional shot for our random gallery this week, by our junior ButterflyCircle member, Jonathan Soong. Our 13-year old teenage talent consistently produces work that is on par with the seniors, and far exceeds that of many 'weekend photographers'.  In this shot taken last weekend, a nicely composed Gram Blue sitting on a leaf of a Leguminosae accentuates the butterfly with a clean background. The leaflet 'triplet' below the butterfly frames and underscores the subject effectively, giving an eye-pleasing composition.

The Gram Blue is moderately common and can sometimes be abundant in certain locations at times.  One of Its recorded host plants, Pueraria phaseoloides. a ground creeper, usually grows in open clearings in bright sunshine. The butterfly is active during the hotter hours of the day, and is skittish.  But it settles in the later hours of the day and stops amongst the low shrubbery and tall grasses to rest. 


19 September 2012

Random Gallery - Leopard Lacewing

Random Butterfly Gallery
The Leopard Lacewing (Cethosia cyane)



We feature another immigrant species this week - the Leopard Lacewing (Cethosia cyane).  This species was not present in the checklists of the early researchers and appeared in the Malaysian/Singaporean territory some time in the late 90's and early 2000's.  It is common in Singapore today, and is quite widespread across various habitats.  Its preferred host plant, Passiflora foetida, is a secondary forest "weed", and grows very quickly. 

This shot of a pristine female Leopard Lacewing was taken last weekend by ButterflyCircle member Chng CK.  In the field, the brighter coloured males tend to outnumber females. 

15 September 2012

The Atlas Moth Chronicles - Episode 3

The Atlas Moth Chronicles
Episode 3 :The Circle of Life


After sharing his meticulous documentation of the life cycle of the Atlas Moth (Attacus atlas) in Episodes 1 and 2, Dr Wee Yeow Chin returns to complete his story in this final episode of the Atlas Moth Chronicles.



Episode 2 describes the development of the caterpillars ending in eclosion. However, there was one case that did not end right. The pupating caterpillar somehow ended on the tabletop and began to lay down its silk. Not happy with this, I moved it to a branch with larger leaves (Bridellia sp.) than the original Limau Purut (Citrus hystrix). It continued to lay silk on a leaf for the next 48 hours. Because of the larger leaf size, the caterpillar wasted its silk, leaving none to cover itself. So it ended up as a “naked” pupa.




On the 12th day the caterpillar underwent a final moult, leaving a crumpled mass of old skin on the leaf. From an unattractive, dried looking caterpillar, it turned into a colourful pupa showing the various parts of the future moth. Notice the abdominal segments, folded wings, antennae, mouthparts and head. The pupa wriggled whenever disturbed. The next major change would be eclosion, where the emerging moth leaves its skin behind and crawls out of the silken case. In this particular case I would be able to follow the process unobstructed. Unfortunately I missed the crucial moment. I have only a dissected empty pupa case to show the moulted skin as well as the pupa skin inside the silken case after eclosion.

 
 


Eclosion for this naked pupa occurred at 29 days. I only realised what happened when I found a ragged moth with crumpled wings in the dish it was in. Apparently the emerging moth failed to crawl over the side of the dish and so its wings failed to expand. When I later experimented with removing the top covering of the pupa case to observe the development inside, I found the emerging moth at the edge of my computer table hanging onto a wire until its wings expanded. I had left it on a flat surface but again missed the crucial moment. It was a female and it successfully mated the following day.



The moth with the crumpled wings was left hanging from the edge of a leaf and attracted three to five male moths every night for the next seven nights. However, not a single male copulated with this strange looking female but remained around till nightfall. Was it possible that the female failed to give the necessary courtship signal? Or was it because the males failed to recognise her as a female as her wings were not expanded? In the absence of copulation, she laid about a hundred unfertilised eggs, none of which subsequently hatched.

 
 


In all instances of eclosion the emerging moth remained clinging to the pupa case until nightfall. When it was a male moth, verified by its pair of wide antennae, it would fly off sometime during the night, apparently to seek out newly emerged females. The wider and more elaborate antennae are presumed to enable it to better detect the pheromone discharged by females some distance away. However, an emerging female, with narrower antennae, always remained attached to the pupa case to await a visiting male or males.

 
 
 


Males arrived during the early morning. The first to arrive immediately attached itself to the female. A second male would sometime also cling on to the female. Latecomers simply waited nearby, to fly off the following night. Where there were two males per female, the tip of the abdomen of the first male would make connections with that of the female, thus excluding the second male. The pair remained thus for up to 11-20 hours after which they disconnect but remained attached. Then they flew off, the male probably to seek out another female and the female to lay her eggs on a host plant.

 


To collect the eggs, it would be necessary to cage the pair before they disengage. Egg laying went on for a few days under captivity, giving a total of up to 200-250 eggs per female. The female remained alive for only a few days more. A few of the males that arrived to mate with the newly emerged females failed to survive the next day, dying in the garden, their bodies disintegrating and became food for ants. They probably had visited other females previously before arriving.

 

It was noted with the second batch of 18 pupae that the first wave of emerging moths was males. Females generally emerged later. The number of days from start of pupation to eclosure was 22-23 days for males and 23-25 days for females. This would mean that caterpillars that would develop into male moths had a shorter pupa stage than potential females or they started to pupate a few days earlier. Having males eclose earlier can be a mechanism to discourage inbreeding. The males would have long gone before the females emerge. There is also the possibility of caterpillars “which eventually turn into adult females to pass through one instar more than those which develop into males," as suggested by Henry Barlow. But I failed to detect this in my caterpillars.

Text & Photos by Dr Wee Yeow Chin

Reference : Barlow, H.S., 1982. An introduction to the moths of South East Asia, Malayan Nature Society, Kuala Lumpur

13 September 2012

Random Gallery - Tawny Coster

Random Butterfly Gallery
The Tawny Coster (Acreae violae)



The Tawny Coster is a "foreign talent" that has migrated to Singapore over the past years and has made our little island in the sun its home since 2006.  It is relatively common and widespread in Singapore, being most often observed in urban and secondary forest areas where its caterpillar host plant, Passiflora foetida grows. 

In this week's gallery, we feature a shot taken by ButterflyCircle member Loke PF, who chanced upon this mating pair where the female had just eclosed (and still clinging onto her empty pupal shell) In nature this happens fairly often, where the "early bird catches the worm", or in this case, where the male lies in wait to mate with the female just as she ecloses (or even before!). In extreme cases, particularly in the documented observations of species in the Heliconiinae sub-family, "pupal rape" occurs where the male mates with the female of the same species even when she has yet to eclose, by tearing through the pupal shell!

08 September 2012

Launch of Tampines-Changkat Nature Centre

ButterflyCircle's Community Engagement
Launch of the Tampines-Changkat Nature Centre


MP Irene Ng cuts the ribbon to launch the Tampines-Changkat Nature Centre

After the success of creating a new Butterfly Garden at Tampines-Changkat constituency, which was opened to the public in November last year, the group of enthusiasts under the leadership of Suzana Dawan continued enthusiastically with more roadshows at the constituency level and also at national level exhibitions like the Singapore Garden Festival. 



The Tampines-Changkat Butterfly Interest Group also set up their own FaceBook page to share their activities and members' efforts to improve and sustain the Butterfly Garden.  Member of Parliament Irene Ng further encouraged the members to engage and educate the community, and the Butterfly Garden had regular visiting groups from nearby primary schools and residents keen to learn a bit more about butterflies. 





MP Irene Ng then supported the conversion of an unused facility at the Housing and Development Board (HDB) void deck at Block 124, Tampines Street 12, into a Nature Centre for the group.  On 1 Sep 2012, the Tampines-Changkat Nature Centre was officially opened at a short ceremony by MP Irene Ng.




Young ButterflyCircle members Jonathan Soong and Brian Goh share their knowledge about butterflies with MP Irene Ng

ButterflyCircle is happy to have been involved in an advisory role in some of the activities of the Tampines-Changkat Butterfly Interest Group.  Members also turned up to support the Opening Ceremony of the Nature Centre.  ButterflyCircle's mission and members work were showcased at a booth during the Opening Ceremony.  Books by ButterflyCircle members were also available for sale.



The event was attended by a small crowd from the area and MP Irene Ng cut the ribbon to declare the Nature Centre open.  Butterfly breeding efforts were showcased at the Nature Centre, as well as information, photographs and exhibits about butterflies.



The Children's Colouring Competition in progress (above) and winners and participants with MP Irene Ng

In conjuction with the opening, a Children's Colouring Contest and a Photography Competition were also organised. ButterflyCircle member Koh Cher Hern's submission won him the 2nd Prize in the Photography Competition.  




Judging of the Photography Competition and ButterflyCircle member Koh Cher Hern with his 2nd prize effort

The Malay Press, Berita Harian also picked up the news and featured the opening in a short article in the following day's paper.  It highlighted the Nature Centre's mission to educate and inject in today’s generation as well as the next, to explore, respect and love nature. The centre was believed to be the first hub to house various activities and special exhibitions on local flora and fauna in a HDB neighbourhood.  This is also to educate residents about butterflies, their caterpillars and relationships with plants.



Judges of the two competitions pose with MP Irene Ng

The Nature Centre is about the size of a 3-room HDB flat and features an exhibition area, a meeting room, and an general purpose area for discussions, talks and presentations.  It is hoped that, at this new "HQ" for the Tampines-Changkat Butterfly Interest Group, more ideas will be conceived to promote nature- and butterfly-friendly activities and education efforts that will encourage the community to learn more and appreciate butterflies and nature in general.


This Lime Butterfly caterpillar knows how to pupate exactly at the location that depicts its future beautiful form!

The next project would be to expand the existing Butterfly Garden's landscaping into the external areas surrounding the enclosure, and perhaps to even add in a community eco-pond to attract dragonfly biodiversity to Tampines!

Text by Khew SK :  Photos by Anthony Wong and courtesy of Tampines-Changkat Butterfly Interest Group