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

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

Butterfly Courtship Rituals

Butterfly Courtship Rituals
Success strategies in finding the right mate

A large part of a butterfly's lifespan is spent directly or indirectly to achieve a particular objective - that of procreation.  A newly eclosed butterfly spends most of its day feeding to build up its reserves and energy so that it can survive and search for a mate and to quickly ensure the continued survival of the species before it dies or succumbs to predation.

For a butterfly to be able to fulfil its objective of mating and producing viable eggs for the next generation, the males and females have to first locate each other.  Males have to correctly identify a female of his own species by visual cues.  A variety of characteristics, from colour, pattern, size, flight and other behavioural attributes that may not be apparent to the human eye, are used to assess the butterflies that they encounter. 

Locating a Mate

So where does a fertile male go to look for potential females to mate with?  Males generally have two main strategies.  The first is perching or hill-topping.  Basically, this method requires the male to search out a high vantage point from which he can have a clear view of an area.  The moment an intruder or any movement is detected, the male will dart down and check out the newcomer into his territory. 

If the intruder is a male, or a butterfly of another species, the male dives into the path of the newcomer and "attacks" it.  An aerial dogfight ensues, until the intruder leaves the incumbent's territory.  The resident male then returns to one of several favourite perches, and then continues to monitor his domain for new activity. 

Hilltops or tall trees with the surrounding vegetation lower are ideal places for the 'perching' strategy.  Hence such places function as a "singles' club" for both males and females of a species to find each other.

The second strategy employed by males of butterflies is what is referred to as "patrolling".  The male flies continuously along tracks, forest edges and streams to look out for females.  As it detects females by visual contact, it will check out anything that is in motion and even if it vaguely resembles a female of its own species. 

Some males also patrol near its caterpillar host plants, with the objective of finding a newly-eclosed female of the same species.  A well-known phenomenon amongst the Heliconiinae of South America is "pupal rape" where males of a particular species tear through the pupal shell of a female of the same species to mate with her even before she ecloses! 

Courtship

When a male locates a female of his own species, it will switch to courtship mode and track the female persistently.  He then begins the rituals of courtship.  For the male, finding the prospective mate is just the beginning.  There are still no guarantees that the female will considering him worthy of fertilising her offspring. 

The female being courted will assess and choose the male depending on age, general appearance and health and potential ability to provide viable spermatophore for her reproductive success.  Females of many species tend to mate only once so her choice is crucial.  Indeed, many ButterflyCircle members have observed an ovipositing female, collected the eggs for breeding, only to find that the eggs were infertile and did not hatch at all!  Could that be due to her eggs not being successfully fertilised by the male? 

Courtship for the male commences with trying to get the female's attention, via a series of signals, ranging from flapping around the female to gain her attention (she may be going around her own business of feeding for example), sending chemical signals to her, in the form of pheromones.  A typical movement is where the male flaps in position, usually upwind from the female, and release his pheromones so that she gets a clear signal of his intention to mate. 

In the male, pheromones are usually found in the specialised scales on various parts of the wing - called androconial cells, specialised organs like the hair pencils in Danaianae species, or hair brushes on the undersides of the wings brushing against a special scent organs on the wings. 

Rejection

The female which picks up the signals then decides on her next course of action.  She may continue with her own business and fly away, totally ignore the male.  Of course, the male usually being persistent in his courtship attempts (like some men do in our human world!), will take the initial rejection in his stride and continue to re-send the physical and chemical signals to the female repeatedly.

Once again, the female may fly off, indicating that she is not interested.  This can go on for several attempts before the female responds, or continues to reject the male until he gets the message and gives up. 

In some cases, the males are more aggressive and flies in such a way as to obstruct the female's ability to fly off, or corners her.  If the female is still not interested, she will usually stop with her wings opened, and adopt her "rejection posture".

This is usually done with her wings opened either fully flat or half-opened, but with her abdomen thrust upwards and elevated such that it would be all but impossible for the male to clasp the end of her abdomen.  A persistent male may still flap violently above the female and try to push her abdomen down, but he will usually fail, and fly off after a few attempts.

Success at Last!

If the female responds positively and decides to accept her suitor's advances, she will close her wings and remain still.  This signals the male to now approach her.  He will land beside her, flick his wings a few times, moves beside her facing the same direction, and curls his abdomen towards hers and grasps hers using his claspers.  The receptive female will extend and offer her abdomen for coupling. 

Once engaged, the coupled butterflies will face away from each other in the usual mating pose,  Usually, if disturbed, the larger wingspan of the two (usually the female) will do the flying, whilst the other partner remains still.  It would be unimaginable for both to fly at the same time, and in opposite directions!

In the field, we have seen impatient male butterflies hovering around pupae from which females are about to eclose, and immediately mate with them when the female breaks out of her pupa.  Copulation occurs even before the female is able to dry her wings properly.  In one case, the male was so insistent on 'doing it' that he damaged the wings of the female, leaving her crippled and unable to fly!

In other cases, we have also observed males of various species coupling in flight in an instant, dispensing with the long courtship rituals and avoid suffering the fate of rejection.  One example that I have personally witnessed, was when a male, perched on a high vantage position, swooped down on a passing female, engaged her in mid-air, and both fell downwards, coupled into the bushes and stayed mated for quite some time!  Now that, I would call precision engagement!

And so we see how in the world of butterflies, males have to woo their mates and work hard before they can successfully mate with a female of their choice.  Males will often have to suffer the 'indignity' of rejection as there are no guarantees that the female that they have targeted, would accept them, no matter how hard they try.  But like all things in life, success always comes to those who are persistent in the face of failure and work hard for it. 

Text by Khew SK : Photos by Sunny Chir, Federick Ho, Khew SK, Terry Ong & Anthony Wong

References :

• Handbook for Butterfly Watchers : Robert M Pyle, 1984, 1992; Houghton Mifflin Company, New York
• A World for Butterflies - Their Lives, Behavior and Future : Dr Phil Schappert, 2000; Firefly Books
• Butterflies : Dick Vane-Wright, 2003; The Natural History Museum, London