04 February 2012

Life History of the Blue Glassy Tiger

Life History of the Blue Glassy Tiger (Ideopsis vulgaris macrina)



Butterfly Biodata:
Genus: Ideopsis Horsfield, 1857
Species: vulgaris Butler, 1874
Subspecies: macrina
Fruhstorfer, 1904
Wingspan of Adult Butterfly: 65mm
Caterpillar Local Host Plant: Tylophora flexuosa 
(Apocynaceae, synonym: T.  tenuissima)

Physical Description of Adult Butterfly:
Above, the wings are mostly bluish grey with veins and all margins blackened. On the hindiwng, the bluish grey streaks in the cell form a  narrow V with its apex pointing to the wing base. On the forewing, there is a transverse black bar towards the distal cell-end.  Underneath, the markings resemble those on the upperside but in lighter colour.The male has a distinct brand near the sub-tornal area of the hindwing.





Field Observations of Butterfly Behaviour: 
This species is locally common in Singapore and is most   likely encountered in coastal mangrove habitats such as the Sungei Buloh Wetland Reserve and Pasir Ris Park. Occasionally the adults can also be spotted in some urban parks and gardens. Blue Glassy Tiger shares the same habitats with the similar-looking Dark Glassy Tiger (Parantica agleoides agleoides) and the two are difficult to tell apart when they are in flight. Once settled on a perch, Blue Glassy Tiger can be identified by the presence of the transverse bar in the forewing cell, a feature not present in the Dark Glassy Tiger. The sun-loving adults are slow and undulating in flight, and prefers open but sheltered environments.





Early Stages:
The local host plant  is Tylophora flexuosa,  a climber typically found in back mangrove habitats.  The caterpillars of Blue Glassy Tiger feed on the young and  tender leaves in its early instars but move on to the more mature and larger leaves in  later instars.

Local host plant: Tylophora reflexuosa.

A mating pair of the Blue Glassy Tiger.

The eggs of the Blue Glassy Tiger are laid singly on young leaves or  a slender stem of the host plant. The white egg resembles a rugby ball standing on one end  (about 1.75mm in height). The egg surface is transverse ribbed and is adorned with  shallow vertical ridges.

Left: fresh egg; Right: mature egg. Note the black head is visible in the mature egg.

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 2.6-2.7mm. Its cylindrical body is whitish and has a fair number of short setae. The large head capsule is black in color. A pair of very short and pale  brown protuberances can be found on the dorsum of the 2nd thoracic and the 8th abdominal segment. Another pair of small black dash-shaped patches are visible on the dorsum of the prothorax. All eight pairs  of legs are black in colour and there is a large black patch at the posterior end.


Two views of a newly hatched caterpillar, length: 2.3mm.

Once the newly hatched moves on to feed on the young leaves over the next few hours, its body starts to take on a wine red coloration, and numerous white oval-shaped markings appear. The two pairs of protuberances becomes wine-red in colour and are longer and projected outwards.   The growth is rather rapid with the body length about doubling in about 1-1.5 days, and after just 1.5 to 2 days from hatching, it moults to the 2nd instar.


Two views of a 1st instar, late in this instar, length: 5.1mm.

Two views of a 1st instar caterpillar, dormant before its moult, length: 4.5mm.

The body of the 2nd instar caterpillar is dark wine red to dark purplish brown in base colour, and is ornamented with numerous small white dots. The short protuberances on the 2nd thoracic and 8th abdominal segments in the 1st instar have become longer and fleshy processes with the pair on the mesothorax much longer.  This instar lasts about 2  days with the body length reaching 7.5-8mm before the moult to the 3rd instar.

Two views of a 2nd instar caterpillar, early in this stage, length: 5.8mm


Two views of a 2nd instar caterpillar, length: 7.5mm

The 3rd instar caterpillar is similar in appearance to the 2nd instar caterpillar with the only change being the proportionally longer processes. This instar takes about 2 days to complete with body length reaching about 13-14mm.


A newly moulted 3rd instar caterpillar next to its exuvia, it head capsule yet to fully turn black.


Two views of 3rd instar caterpillar,  length: 11.5mm


Two views of a 3rd instar caterpillar, late in this stage, dormant before its moult,  length: 13.5mm

Retaining very much the same body features from the earlier two instars, the 4th instar caterpillar distinguishes itself in having proportionally longer processes, the meso-thoracic pair of  which have the tendency to flex forward. The lower one-quarter of each of the four processes is coloured in dark red. This instar lasts about 2 days with the body length reaching about 21-24mm.


Two views of a 4th instar caterpillar, newly moulted, length: 13.5mm.


Two views of a 4th instar caterpillar,   length: 24mm.


Two views of a 4th instar caterpillar, late in this stage, dormant before its moult, length: 21mm.

The 5th and final instar resembles the 4th instar closely albeit with a noticeable increase in the size of the white spots which are thus packed closer to each other.


A freshly moulted 5th instar caterpillar, with its exuvia trailing behind.


Two views of a newly moulted 5h instar caterpillar, length: 21mm.


Two views of a 5th instar caterpillar,  length: 31mm.

The 5th instar lasts for about 3.5-4 days, and the body length reaches up to 34mm. On the last day, the caterpillar ceases feeding. Its body becomes shortened and the dark purplish brown base colour decolorises to a dark shade of grey, and the wine red colour in the basal part of the processess turns white. The fully grown caterpillar  wanders around in search of a pupation site. Typically it comes to a halt on a branch/stem or a leaf underside, where the caterpillar spins a silk pad from which it  next hangs vertically to take on the pre-pupatory pose. The body gradually takes on a yellowish tone during the pre-pupal stage.  Within the few hours prior to pupation, the caterpillar gradually relaxes and lengthens to a straight posture. Waves of contraction soon travel from the the rear end to the head until the pupation event kicks in.


Pre-pupatory larva. Left: early stage; Right: late stage with the onset of pupation only minutes away.


The pupation event of a Blue Glassy Tiger caterpillar.

Pupation takes place about 0.5 days after the caterpillar assumes the hanging posture. Typical of the pupae within the Nymphalidae family, the pupa of the Blue Glassy Tiger suspends itself from the silk pad with no supporting silk girdle. The pupa is bright yellowish green and is somewhat barrel-shaped. It has a median transverse whitish line marked with a series of black spots. Several scattered silvery spots adorns the dorsum of the thorax and the wing pads. Two thick black streaks lie close to the black cremaster on the dorsal side.  Length of pupae: 18-20mm.


Three views of a pupa of the Blue Glassy Tiger.


Three views of a mature pupa of the Blue Glassy Tiger.
The pale streaks and some of the spots  can be seen in the wing pad area.


After about 7 days of development, the pupal skin turns translucent as the development within the pupal case comes to an end. The spots/streaks on the forewing upperside also become discernible. The following day, the adult butterfly emerges from the pupal case. It then perches nearby to expand and dry its wings before taking its first flight.


A newly eclosed Blue Glassy Tiger drying its wings while clinging onto 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.
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 1st Edition, 2006
Text by Horace Tan, Photos by Simon Sng, Sum CM, Nelson Ong,  Loke PF,  Federick Ho,  and Horace Tan

29 January 2012

Butterfly of the Month - January 2012

Butterfly of the Month - January 2012
The Leopard Lacewing (Cethosia cyane)




















When I started this blog back in Aug 2007, it was a spur of the moment decision, as I wanted to try my hand at blogging in a less frivolous manner than what blogs back then (and perhaps even today) stood for. There were blogs, and there were blogs. An entire spectrum still exists today - from technical and information-rich blogs to the casual and personal diaries of individuals keen to share their perspectives to whomever has the time to read their rantings and trivia.




















The Butterflies of Singapore Blog is now moving into its fifth year since the first article was published, and I hope that it will continue for as long as there is information to share about our beloved butterflies, and the exceptional photographic talent of my friends from ButterflyCircle to showcase to the world.



















Special mention must be made too, of my fellow-blogger on this site, Horace Tan, who has meticulously and painstakingly recorded so many butterfly species' early stages - some of which has been recorded in such detail for the first time. Horace's work far exceeds the work of any amateur enthusiast that I know of, and sets the benchmark, both in photography of the early stages of butterflies, and the scientific write-up that accompanies each impressive blog article.




















2012 started off quietly enough, as unique challenges continue to plague each geographical region all around the world. Amidst all the sombre news as we bade 2011 goodbye and welcomed 2012, there are always optimistic outlooks and predictions in the year ahead. Doomsday theorists predict that the end of the world is nigh, and that day will happen on 12 Dec 2012.



















This day, which happens to be a Wednesday, marks the conclusion of the b'ak'tun - a time period in the Mesoamerical Long Count Calendar, usually associated with the Mayan civilisation. Prophetic beliefs hold that the world, as we know it, will end on this day, caused by a cataclysmic event, and where time on earth ends. Even Hollywood jumped on the 2012 Phenomenon with a movie, aptly titled 2012. If fantasy is to be believed, somewhere in China, a whole bunch of people would almost have completed the construction of a number of arks to save a select group of Earth's most illustrious and financially well-endowed citizens.




















Back to a more optimistic frame of mind, nature still has a lot of beauty for us to enthrall and amaze our senses. Let's leave the end of the world to the people who prefer to see things that way. January's birth flower is the carnation, a pretty flower that comes in all manner of colours.


A species that originated from over 2000 years ago, and originally came in only pink, there are many cultivars today that adorn flower arrangements and myriad uses that celebrate the flower's beauty. Dianthus caryophyllus as scientists know it, represents various meanings to different cultures and even the colours stand for a variety of interpretations from admiration, deep love, luck and capriciousness!




















In our world of butterflies, we start the new year off with a colourful and very attractive butterfly, the Leopard Lacewing (Cethosia cyane). This species belongs to the subfamily Heliconiinae of the Nymphalidae family, of which many of the species are feeders of the host plants from the Passion Fruit family. Many of the species are colourful and attractively patterned, and display aposematic colouration.




















The Leopard Lacewing was not recorded in the early authors and researchers' lists of butterfly fauna in Malaysia and Singapore. The species has a range spanning from India to Southern China, and its arrival in peninsula Malaysia and Singapore is fairly recent. In his paper in the Malayan Nature Journal Vol 59 Part 1 Oct 2006, "Updating The Butterflies of the Malay Peninsula", the late Col John Eliot added the Leopard Lacewing (Cethosia cyane) and attributed its discovery to Arshad et al in 2000 from the Langkawi Islands. Coincidentally, I happened to be on Langkawi that year, and captured a number of the species for record. These specimens are featured in Col Eliot's article's accompanying colour plates, showing a male and female of the Leopard Lacewing from Langkawi Islands.




















Not much data is available of the spread of the species southwards in the Malay Peninsula. The first record of a sighting of a female of this species was during an official biodiversity survey in the Western Catchment area on 13 Dec 2005. A voucher specimen was taken, and recorded in NParks' survey data. Another female was spotted at the Upper Seletar Reservoir Park on 7 Jun 2006, and thereafter, the species became very widespread across Singapore wherever its host plant, which it shares with the Tawny Coster (Acreae violae) another immigrant, is found.




















The male Leopard Lacewing is orange above with black apical and submarginal borders. It appears similar to its two related species - the Malay Lacewing and the much rarer Plain Lacewing. The distinct and large submarginal black spots on the hindwing above sets it apart from the other two species. On the underside, these black spots, set in a narrow white submarginal band, distinguishes its two closest relatives.




















Female Leopard Lacewings are a pale creamy yellowish-salmon coloured above and have a similarly coloured dorsal patch on the forewing as the males. The underside also features the same pattern as above, and the ground colour is also the pinkish-salmon colour.





























The butterfly is common in open areas as well as the forest edges where its host plant, Passiflora foetida (Stinking Passionflower) is found. The plant is a secondary forest "weed" and appears whenever there are areas cleared and left untended for periods of time. The female Leopard Lacewing oviposits a large number of eggs on the underside of a leaf of the host plant, and the caterpillars can defoliate the plant very quickly due to the sheer number that usually hatch from the 20-50 eggs per clutch.




















The caterpillars feed together in a group, until the late instars. Attractively striped in cream and deep red, the caterpilars also display aposematic colouration to display to predators that they are distasteful. The pupae are oddly shaped and variable in colour and well camouflaged when in the undergrowth.




















The Leopard Lacewing is easy to breed, and is one of the feature butterflies that are fairly common at Oh' Farms Butterfly Lodge, a facility set up for educational research and conservation of butterflies by a private sector organisation in Singapore.




















As we start off this first month of 2012 with this very pretty and attractive Leopard Lacewing, we look forward to 2012 (and beyond the "end of the world") and to more butterfly stories in this blog. On behalf of ButterflyCircle, we take this opportunity to wish all our Chinese readers and members a Happy and Prosperous Year of the Dragon and Gong Xi Fa Cai!

Text by Khew SK : Photos by James Chia, Sunny Chir, Federick Ho, Khew SK, Jonathan Soong, Horace Tan, Anthony Wong & Mark Wong



22 January 2012

Life History of the Common Red Flash

Life History of the Common Red Flash (Rapala iarbus iarbus)


Butterfly Biodata:
Genus: Rapala Moore, 1881
Species: iarbus Fabricius, 1787

Subspecies: iarbus  Fabricius, 1787
Wingspan of Adult Butterfly: 32-37mm
Caterpillar Local Host Plants:
Mimosa pigra (Fabaceae, common name: Giant Sensitive Tree), Melastoma malabathricum (Melastomataceae, common name: Singapore Rhododendron).

A male Common Red Flash, note the circular bulge on the hindwing, indicating the presence of the circular brand on the upperside.

A sunbathing male Common Red Flash, note the trident mark on the forewings.

Physical Description of Adult Butterfly:
Above, the male is red to orange with dark brown costal and distal border on the forewing, veins 2, 3 and 4 of which have their bases clothed with dark brown scales, forming the so-called trident mark. In contrast, the female is a dull coppery brown throughout. As with all Rapala species, the male has a circular brand near the base of space 7 on the hindwing. Underneath, both sexes are pale greyish buff. On both wings, there is a cell-end bar and a narrow pale brown post-discal line which is whitened on the outer side. The hindwing has a prominent, tornal, black, orange-crowned spot in space 2 and a smaller one on the tornal lobe. Between the two spots, the marginal area in space 1b is covered with bluish scaling. There is a white-tipped tail at the end of vein 2. The legs are white and black-banded.

The orange-crowned spot on the tornal lobe of a Common Red Flash adult.

A female Common Red Flash sunbathing on a leaf perch.

A sunbathing female Common Red Flash showing us its uniformly brown upperside.

Field Observations:
This species is moderately uncommon in Singapore and its distribution is  localised to a few sites in and along the fringe of the nature reserves and a few wastelands where its host plants, Mimosa pigra and the Singapore Rhododendron,  are growing in relative abundance. Both sexes have been observed to visit flowers and  sunbathing with open-wings in later afternoon.  These sunbathing routines for the males are regularly interrupted by vigorous dog-fighting among them.






Early Stages:
The Common Red Flash is polyphagous as its early stages feed on a number of host plants from different families
Locally two plants, Mimosa pigra and Melastoma malabathricum, have so far been identified as the larval host. C&P4 also lists Nephelium lappaceum (Rambutan) and Melastoma polyanthums as hosts in the Malay Peninsula. The caterpillars of the Common Red Flash feed on the flower buds,  flowers, ripened fruits as well as young leaves of the host plants.  In the wild, the caterpillars are typically found in the company of the ant Anoplolepis longipes  [C&P4]. 

Local host plant #1: Mimosa pigra.

Local host plant #2: Melastoma malabathricum.

A mother Common Red Flash ovipositing on the stem of Mimosa pigra.

The eggs are laid singly on leaves, stems or young shoots of the host plants. Each egg is about 0.6mm in diameter, green in colour. It is burger-shaped with a depressed micropylar at the pole and a surface covered in a  reticulated pattern of intersecting  shallow ridges.

Two views of an egg of the Common Red Flash.

A maturing egg of the Common Red Flash.

It takes about 3-4 days for the egg to hatch. The pale yellowish brown newly hatched has a length of about 1.1mm and has bands of brown patches laterally and dorsally. Dark brown patches can be seen on the 1st, 7th-8th abdominal segments and on the anal plate. It also has a black prothoracic shield and a black head. The body also features fine setae dorsally and laterally.


1st instar caterpillar, early in this instar, length: 1.6mm

Two views of a 1st instar caterpillar, late in this instar, length: 1.9mm..

After about 3-3.5 days of growth in the first instar, and reaching a length of about 2.2mm, the caterpillar moults to the next instar. The black patches on the 1st, 7th-8th abdominal segments and on the anal plate seen in the first instar  are now in paler brown. The prothoracic shield is similarly changed. There are numerous short fine setae emanating from rows of conical projections occurring dorso-laterally. Numerous short setae are also projected sub-spiracularly along the body fringe. 

Two views of a 2nd instar caterpillar, length: 4mm.

The 2nd instar caterpillar reaches a length of about 4-4.5mm, and after about 4-5 days in this stage, it moults again. Compared to the 2nd instar caterpillar, the yellowish green 3rd instar caterpillar has a more striking appearance with oblique dorso-lateral  patches outlined in white. The dorsal nectary organ is morely readily observed now. The 3rd instar takes about 3 to 5   days to complete with the body length reaching about 6mm.

Two views of a 3rd instar caterpillar, early in this stage, length: 4.5mm

The 4th instar resembles the late 3rd instar caterpillar closely. The colour of body markings  is highly variable, ranging from green to pink and even to pale red. It seems that this coloration is closely associated with the colour of the host plant part the caterpillar is feeding on.  The 4th instar takes about 3-6 days to complete with the body length reaching 10mm.

4th instar caterpillars feeding on flower buds (top row) and ripened fruits (bottom row) of Singapore Rhododendron.

 
Two views of a 4th instar caterpoillar, red form, length: 8mm.

Two views of a 4th instar caterpillar, red/green form, length: 8.5mm.

The 5th instar caterpillar has similar markings as in the 4th instar. The body base colour is pale green. There are whitish oblique dorso-lateral stripes on most body segments, and in some caterpillars, these stripes are flanked by dark  spots at their upper end. Conical projections with tuffs of setae are found dorso-laterally and laterally along the body fringe.

Two views of a 5th instar caterpillar, length: 14mm.

Two views of another 5th instar caterpillar, length: 16mm.

After about 5 days of feeding and reaching a length of about 16mm, the caterpillar stops food intake and wanders around for a pupation site. During this time, its body gradually shortened. In some individual the body color fades to a pale shade of green, whilst in others, the body color turns reddish to reddish brown.  At the end of this period, typically the caterpillar chooses a a concealed space in a leaf litter as its pupation site.

Anoplolepis longipes ants attending to a 5th instar caterpillar on a a flower bud of  Mimosa pigra.


Common Red Flash caterpillars in the company of an ant species on Mimosa pigra.

The pre-pupatory caterpillar prepares for pupation by spinning a silk girdle and a silk pad to which it attaches itself via graspers. After 1 day as a pre-pupa, pupation takes place. The pupa is predominantly reddish brown and has numerous small dark  speckles. Pupal length: 9.5-12.5mm. The pupa has a typical  Lycaenid shape with a relatively longer abdomen.

Two views of a pre-pupa of the Common Red Flash  (green form)

Two views of a pre-pupa of the Common Red Flash (red form)

Two views of a pupa of the Common Red Flash.

Seven to eight  days later, the pupa turns rather black, first in the wing pad and thorax, then progressively in the abdomen. The presence and absence  of orange/reddish patch in the wing pads gives an early indication of the gender of the soon-to-emerge adult. The next day, the pupal stage comes to an end with the emergence of the adult butterfly.

A mature pupa of a male Common Red Flash.

References:

  • [C&P4] 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  Nelson Ong, Sunny Chir, Khew SK and Horace Tan