Life History of the Dark Posy

Life History of the Dark Posy (Drupadia theda thesmia)

Following the earlier blog article on the Three Posies, Horace Tan shares his latest discovery on the life history of one of the Posies - the Dark Posy.

Butterfly Biodata:
Genus: Drupadia Moore, 1884
Species: theda C. & R. Felder, 1862
Subspecies: thesmia Hewitson, 1863
Wingspan of Adult Butterfly: 35mm
Caterpillar Host Plants: Combretum sundaicum

Physical Description of Adult Butterfly:
The typical form of the male is dull purple above, whereas the -f minara form has an orange discal patch on the forewing. The female is brown, with a bluish grey tornal patch on the hindwing which has a few black submarginal spots. On the underside, the forewing is orange brown in the male and orange in the female, and the hindwing is mainly white; the forewing is marked with darker transverse stripes, and the hindwing markings consist of black spots and lines, with metallic green scalings and black spots at the tornus. There are three pairs of tails at the end of veins 1b, 2 and 3 on the hindwing. The species can be distinguished from the rather similar D. ravindra (Common Posy) in that the space between the two black stripes forming the cell-end bar on the underside hindwing is white, and not filled in with black as with D. ravindra.

Field Observations of Butterfly Behaviour:
This species is relatively rare in Singapore and it is mainly found at localised areas within the Central Catchment Area where the host plant Combretum sundaicum is common. In the early afternoon, the adult butterflies can be spotted flying from one perch to another perch in quick zig-zag flights. In sunny weather, they have the habit of fully opening their wings to sunbathe.

Early Stages:

Host plant : Combretum sundaicum


Host plant : Combretum sundaicum, young shoot

Eggs are laid singly on the young stem or the petiole of the liana (woody climber) Combretum sundaicum. Each egg is white with a beige tinge; circular with a depressed micropylar area and has many tiny pits dotting the surface. With a diameter of 0.9mm, the egg is rather large for a lycaenid species.


Egg of Dark Posy


Mature egg (top), empty egg shell (bottom)

It takes 2 days for the collected egg to hatch. The young caterpillar eats away the upper portion of the egg shell to emerge. With a length of about 2mm, it is cylindrical with long setae (hairs) and pale green in color. As it grows, it will assume the more typical onisciform (woodlouse) shape.


1st instar caterpillar, newly hatched, length: 2mm


1st instar caterpillar, 2.5mm

The 1st instar caterpillar feeds by skimming the surface of a young leaf. After 2 days of growth, and reaching a length of about 4mm, its moults to the next instar. The second instar caterpillar has short fine hairs covering its body and two stripes of faint white markings flanking the green dorsal ridge. The prothoracic shield is diamond in shape but rather inconspicuous. The feeding is still done via eating away the upper layer of the leaf surface.


2nd instar caterpillar, early in this stage, length: 5mm

The 2nd instar caterpillar reaches a length of about 7mm, and after 2 days in this stage, it moults again. In the 3rd instar, the dorsal markings are more prominent and the anal plate also features a fine red line. The caterpillar now feeds by eating along the leaf edge and devours the whole leaf. The typical lycaenid nectary organs (both dorsal organ and lateral tentacular organ) are now discernible. Even in the absence of ants, the dorsal organ excretes plentiful amount of clear fluid, suggesting a strong caterpillar-ant association in the wild. The 3rd instar takes 3 days to complete with the body length reaching about 10-11mm.


3rd instar caterpillar, length: 9.5mm


3rd instar caterpillar, length: 9mm, resting for the moult to next instar

The 4th (and final) instar caterpillar still has the same dorsal markings as in earlier instars, but the prothoracic shield has taken on two vertical rows of black, saw-toothed markings. New to the anal plate is a small oval-shaped area marked with a short black bar. The 4th instar takes about 4 days to complete with the body length reaching 20-21mm. Nearing the end of this instar, the caterpillar ceases feeding, and its body shrinks in length. Soon it comes to rest on the leaf surface and becomes an immobile pre-pupa.



4th instar caterpillar, early in this stage, length: 14mm


Pre-pupa of Dark Posy

The pre-pupa caterpillar prepares for pupation by spinning a silk girdle and a silk pad to which it attaches itself via cremastral hooks. Finally after 12 days of larval growth, pupation takes place. The pupa has a shape typical of any lycaenid species, and a length of about 14mm. It is light yellowish brown and dotted with small black specks.


Fresh pupa of Dark Posy

Seven days later, the pupa becomes darkened in color signaling the imminent emergence of the adult. The uppersides of the forewings become visible through the now transparent pupal skin, allowing one to tell the gender of the soon-to-appear adult. The next day the adult butterfly emerges from the mature pupa.


Mature pupa of Dark Posy (male)



A newly eclosed Dark Posy resting on young leaf of its host plant


Another Dark Posy in the field

References:

• The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
• The Butterflies of Hong Kong, M. Bascombe, G. Johnston, F. Bascombe, Princeton University Pres 1999

Text and Photos by Horace Tan

Butterfly of the Month - April 2008

BUTTERFLY OF THE MONTH - APRIL 2008
The Plane (Bindahara phocides phocides)

The Plane belongs to the genus Bindahara of which this species is the only representative in Singapore. It is very rare and local in distribution, found mainly in a small area at the forest edge of the Central Catchment Nature Reserves. Some prominent physical features of the Plane are the long hindwing tails (2 cm or longer) and pendulous tornal lobe on the hindwing.

The male of this species is a deep blackish brown above with the apical area of the forewing dusted brownish red. There is a narrow blue marginal line above vein 4 on the hindwing in some individuals. The female is reddish brown with a large black spot in space 2 of the whitened tornal area of the hindwing.

The undersides of the males are ochreous buff, with darker brown bands on the forewings, and spots on the hindwings. There are black tornal spots on the lobes and spaces 1b and 2 on the hindwing are overlaid with metallic green scaling. The long tails of the males are yellow.

Females feature whitish ground colour on the undersides, with similar marking as in the males, with the apical areas of the forewings a light orange-brown. The tails of the females are white. Both sexes have orange tipped antennae, and large jet black eyes. The adult butterfly has a wingspan of about 40mm.

The Plane can be observed in the late morning on sunny days, either feeding on the flowers of flowering trees like the Syzygium spp., and the forest bush Leea indica of which many of these photos feature, or just flitting amongst the tall leaves of bushes and trees in the nature reserves. In Singapore, males are more often encountered than females.

The Caterpillars of this species are basically white with areas of yellow and pink, but they have dark brown tubercles on each segment each bearing a black hair. The Caterpillars grow to a length of about 2 cms. They feed on the seeds within the fruit of Salacia chinensis and Salacia disepala. The Caterpillars bore into the bark of the tree to pupate. The pupa is brown and rough, with patches of white and dark brown. Its length is about 1 cm. When disturbed, the pupa emits clicking noises.

Text by Khew SK ; Photos by Khew SK & Federick Ho

References :

• Don Herbison-Evans & Stella Crossley : "Caterpillars of Australia" - Life History of Bindahara phocides yurgama

Life History of the Lime Butterfly

Life History of the Lime Butterfly (Papilio demoleus malayanus)

An updated version of the life history of the Lime Butterfly is available by clicking on this link.

Butterfly Biodata :

Genus : Papilio (Linnaeus, 1758)

Species : demoleus (Linnaeus, 1758)
Subspecies : malayanus (Wallace,1865)
Common name : Lime Butterfly
Wingspan of Adult Butterfly : 60 – 80mm
Caterpillar Host Plant : Citrus microcarpa

Physical Description of Adult Butterfly :

On the upperside, the wings of the Lime Butterfly are black with large yellow markings. These form an irregular macular fascia running from the apex of the forewing to the mid-dorsum on the hindwing, and there is a series of yellow submarginal spots on both wings. At the bottom of the hindwing (space 1b) is a red spot with an anterior narrow blue lunule. As for the female, this blue lunule forms the anterior portion of a large black circular spot above the red spot. The underside is predominantly yellow with a series of reddish post-discal bars on the hindwing.

Field Observations of Butterfly Behaviour :

This butterfly is common in gardens wherever the host plants of the species, Citrus spp. are cultivated. It is a strong flyer with a rapid erratic flight. It flies from flower to flower in search of nectar. Like many Papilionidae it has a characteristic flight when feeding, in that whilst the forewings are flapping rapidly, the hindwings are held almost stationary as if to balance the butterfly perched on a flower as it sucks nectar from the flower with its long proboscis.

In the cool morning hours, the Lime Butterfly may be found resting amongst shrubbery, sunbathing with its wings opened flat, as if to warm up before taking flight and going about the day's business.

An interesting phenomenon, particularly in the more affluent Asian countries, is that during the Lunar New Year celebrations, the Lime Butterfly appears to be more common than usual, due to the discarded Citrus plants which are traditionally purchased with the orange fruits ripened, to signify wealth during this Chinese festival. With the abundance of its host plant during this season, the female Lime Butterfly will waste no time ovipositing on the available host plants.

Early Stages :

The eggs are oviposited singly on the young leaves of the Citrus host plant. The egg is smooth, round and yellowish in colour, measuring around 1mm in diameter.

The egg of Lime Butterfly

After about 3-4 days, the caterpillar hatches from the egg, and immediately starts to consume the eggshell completely. The caterpillar then starts to eat the young leaf that the egg was laid upon.

The 1st instar caterpillar has a spiky appearance. The colour of its body is brown with yellowish-white markings with white hairs. As it feeds, the caterpillar usually stays in the middle of the upper side of the leaf. The first few instars of the caterpillar resemble bird droppings where it escapes predation by camouflaging itself in this manner.

1st instar Lime Butterfly caterpillar (3mm) consuming its eggshell upon hatching

As it moults into the 2nd instar, the dirty greenish-brown colour of its body remains similar as the 1st instar except that the saddle white band has widened somewhat. The hairy spikes of the 1st instar now take a more solid rubbery appearance.

2nd instar Lime Butterfly caterpillar (8mm)

In the 3rd instar is essentially similarly patterned as the 2nd instar. The colour of its body becomes richer, with white patches appearing near its head and last abdominal segments. It has an oily glossy appearance.

3rd instar Lime butterfly caterpillar (14mm)

In the 4th instar caterpillar, more whites patches appear throughout its body, dominating the earlier brown colour. The head also appears lighter in colour.

4th instar Lime butterfly caterpillar (25mm)

In the 5th or final instar, the caterpillar becomes a plain uniform green with a few dark brown markings. It has a pair of false "eyes" near its actual head, appearing much larger and fiercer to ward off predators. Also, when disturbed the caterpillar extrudes a pair of orange-yellow processes from the segment just behind the head, known as osmeterium, to alarm would-be predators.

Final instar Lime butterfly caterpillar (40mm)

After a total of 11 days upon hatching from the egg, the caterpillar then goes into a day of dormant pre-pupation pose after carefully selecting a perch onto which it can pupate upright.

Pre-pupa of the Lime butterfly

The pupa is light green with two projections to the front on its head and also one on its thorax. The abdominal segments are a bright lime green as opposed to the toned down green of the rest of the pupa. A silken girdle helps the pupa stay in an upward position.

Pupa of the Lime Butterfly (10x30mm)

After about 10 days, the pupa shell turns transparent and the wings of the butterfly can be seen through the semi-transparent pupa shell.

Upon eclosion, the adult butterfly emerges and hangs its wings out to dry, as it pumps fluids into the wings to expand them. When its wings are sufficiently dry and hardened, usually after about an hour or more, it takes its maiden flight.

Adult Lime Butterfly (underside view)

Adult Lime Butterfly (upperside view)

Text by LC Goh ; Edited by Khew SK ; Photos by LC Goh, Tan BJ and Neo CB.

Three Posies

Featuring the Common Posy, Dark Posy and Pygmy Posy

One of the definitions of the word Posy is a bouquet. Indeed, the three species of Posy found here in Singapore resemble colourful flowers with attractive black markings. Each species is endowed with three pairs of tails on the hindwings with the tail at vein 2 being the longest of the three.

The Posies belong to the genus Drupadia, of which three species are known to exist in Singapore. All three are forest species and are usually encountered in the nature reserves in the shaded understorey. At times they are found sunbathing with wings opened flat, displaying their blue or purple uppersides. They have a habit of fluttering with a skipping flight, and in some individuals, returning to the same favourite perch time and again. Males generally have a stronger flight than females.

The Common Posy (Drupadia ravindra moorei)

The most frequently encountered species is the Common Posy (Drupadia ravindra moorei). In the male, the forewing is dark brown and the hindwing a very attractive azure blue. The female is mainly brown, with a faint orange discal patch in some individuals. The underside is orange on the forewing with orange and black markings, and mainly white on the hindwing, with black solid bands and spots. Along the tornal edge are iridescent blue scales and the black-centred white tails emerge from veins 1b, 2 and 3, with the tail at vein 2 being the longest.

Upperside of a male Common Posy


Upperside of a female Common Posy

The Dark Posy (Drupadia theda thesmia)

The next species, the Dark Posy (Drupadia theda thesmia) is less often seen but occasionally several are seen together, frolicking at tree-top level in the late hours of the afternoon basking on the tops of leaves when the sun shines through the forest canopy. The male is dark purple above with an orange discal patch on the forewing. This form, f-minara is the typical male form found in Singapore. The female is brown with a bluish grey tornal patch on the hindwing which has a few black submarginal spots.

Upperside of a male Dark Posy


Upperside of a female Dark Posy

On the underside, the forewing is dark orange marked with darker transverse stripes, whilst the hindwing is white with black spots and lines. This species can be separated from the lookalike Common Posy in that the space between the two black stripes forming the cell-end bar on the hindwing beneath is white, and not solid black as in the Common Posy.

The Pygmy Posy (Drupadia rufotaenia rufotaenia)

The final and rarest of the three Posy species in Singapore is the Pygmy Posy (Drupadia rufotaenia rufotaenia). This species, which suggest a small female of the Common Posy, which it resembles. The Pygmy Posy has a wingspan of 20mm, which is about half the size of its other two cousins. In Singapore, it is often seen feeding on the sugary sap of the young shoots of the forest bush, Leea indica, where it stays still for long periods of time unless disturbed.

It can be reliably separated from the other two Posies in that the narrow submarginal orange band on the hindwing beneath is continuous from 1a and extends to vein 3.

Text by Khew SK ; Photos by Khew SK, Sunny Chir, Horace Tan, Federick Ho.

Butterfly of the Month - March 2008

BUTTERFLY OF THE MONTH - MARCH 2008
The Fivebar Swordtail (Pathysa antiphates itamputi)

During certain times of the year, the Fivebar Swordtail can be observed puddling at damp spots along streams and footpaths in the nature reserves of Singapore. It is essentially a forest butterfly and is rarely seen in urban parks and gardens, preferring the sanctuary of the forested reserves .

In Singapore, after a prolonged rainy season towards the end of 2007, the species was rarely seen during the last few months of the year. As the weather turned hotter and drier after the Lunar New Year, a number of Fivebar Swordtails were seen puddling in the nature reserves. During the drier weeks towards the end of February and March 2008, the species became relatively more common and was spotted in various areas around the nature reserves. The species is a favourite amongst butterfly photographers, where it is easily photographed when puddling at damp sandy spots.

When in flight, it can often be mistaken as a Pierid species, as the long tails are not visble when it is encountered flying rapidly along the edges of the forested areas on sunny days. It is swift and erratic on the wing, and when in full flight, seldom stops to rest.

Males of the Fivebar Swordtail are frequently encountered puddling at moist spots. At times, more than one individual is seen, and also in the company of other Papilionidae like the Common Bluebottle (Graphium sarpedon luctatius) and the Blue Jay (Graphium evemon eventus).

The Fivebar Swordtail has the characteristic long, slender and tapering tail at vein 4 of the hindwing, which is consistent in all the species of the genus Pathysa. The Fivebar Swordtail is the only representative of the genus in Singapore. The long sword-like tails are probably the source of inspiration for the common name of the species.

The species is creamy white above with a series of black transverse stripes in the costal area of the forewing and in which the basal and distal interspaces are filled with green. On the underside, the basal half of the hindwing is green, with black stripes and spots, with a distal half of the hindwing orange yellow.

The long tapering white-tipped tails measure about 4-5cm and project elegantly behind the butterfly as it stops to rest or feed. The body of the butterfly is white, with a lateral black stripe along the thorax, and breaking up into dashes along the abdomen. The eyes are an opaque jet black.

The Malaysian & Singaporean subspecies of the Fivebar Swordtail has the distinction of being one of the few butterflies in the region to bear a local name itamputi from the Malay words hitam meaning black, and putih meaning white.

Text by Khew SK : Photos by Khew SK, Wong CM, James Chia, Horace Tan, Simon Sng and Sunny Chir