Wednesday, May 15, 2013

Random Gallery - Common Palmfly

Random Butterfly Gallery
The Common Palmfly (Elymnias hypermnestra agina)



The Common Palmfly is one of three representatives of the genus Elymnias here in Singapore. The rarest one, Elymnias penanga (Pointed Palmfly) was last seen on Pulau Ubin in the early 90's and remains elusive to this day. The Common Palmfly is by far the most common of the three species and is found in urban Singapore, as well as in the forested areas. It has a good range of caterpillar host plants, usually species of Palmae, and many of the host plants are ornamental palms found in urban gardens.

The butterfly very rarely opens its wings to show its more attractive uppersides. The shot here, taken by ButterflyCircle member Loke PF, features the Common Palmfly on the ripened fruit of the Singapore Rhododendron. It is interesting that whilst food is available, even the ants leave the butterfly alone whilst they share the spoils together.


Tuesday, May 14, 2013

Random Gallery - Colonel

Random Butterfly Gallery
The Colonel (Pandita sinope sinope)



This predominantly orange coloured butterfly is considered moderately rare and is a forest-dependent species. It belongs to the subfamily Limenitidinae which features many species with common names that are associated with military ranks and aristocratic peerage. (See earlier blog article on Origin of Some Common Names of Butterflies) The Colonel's wings are dark orange above with dark brown shading in the basal halves of the wings. The underside is a paler orange but with the basal area of both wings a greenish-grey.

This perching Colonel was photographed by ButterflyCircle member Sunny Chir as it was taking a rest from feeding and flying around in a forested patch in the nature reserves. The butterfly is skittish and very alert to potential threats and hence is a challenge to get a good shot of, except perhaps when it is distracted whilst feeding.

Monday, May 13, 2013

Random Gallery - Knight

Random Butterfly Gallery
The Knight (Lebadea martha parkeri)



Last week, we featured the underside of a male Knight on the gallery. Today, we show the upperside of a female Knight. Males have a distinct white apical area on the forewings, whereas the females do not have this characteristic. Featuring a more subdued colour, the female Knight also has the upperside of the hindwing marginal area pale violet-blue. The female Knight has a slightly weaker flight than the male, and prefers to glide gracefully amongst the shrubbery, looking for its caterpillar host plant to lay its eggs on. ButterflyCircle member Koh Cher Hern shot this pristine female Knight perched on a leaf last weekend.

Random Gallery - Purple Duke

Random Butterfly Gallery
The Purple Duke (Eulaceura osteria kumana)



The Purple Duke is a sexually-dimorphic species with the male and female appearing different from each other. Both sexes are skittish and fast-flying and have the habit of flying quickly to the underside of a leaf to hide when alarmed. The brown upperside of the female is reminiscent of the Tanaecia and Euthalia species which share the forested nature reserves with the Purple Duke.

In this shot, taken by ButterflyCircle member Chng CK last weekend, the female Purple Duke adopts a rather interesting pose with her proboscis extended almost horizontally to reach the juices of the ripened fruit of the Singapore Rhododendron.


Saturday, May 11, 2013

Life History of the Painted Jezebel

Life History of the Painted Jezebel (Delias hyparete metarete)


Butterfly Biodata:
Genus: Delias
Hübner, 1819
Species: hyparete Linnaeus, 1758
Subspecies: metarete Butler, 1879
Wingspan of Adult Butterfly: 60-75mm
Caterpillar Local Host Plant: Dendropthoe pentandra (Loranthaceae).




Physical Description of Adult Butterfly:
Above, the wings are white with veins black-dusted towards the outer margins. The female has its veins more heavily black-dusted than the male. Underneath, the wings are white with black-dusted veins. In the hindwing, the basal half is bright yellow and the marginal border is bright orange-red.

A female Painted Jezebel showing us its upperside.


Field Observations of Butterfly Behaviour:
Painted Jezebel is common throughout Singapore with occurrence in multiple habitats in both nature reserves and urbanised areas. This is likely due to its host plant, Dendrophthoe pentandra, being a common mistletoe on many trees in these areas. The adults can be readily seen fluttering tirelessly at tree-top levels during most of the daylight hours. They only descend to take nectar from flowers or to rest in the shaded understorey towards the later part of the day.



Early Stages:
The Painted Jezebel has only one local host plant recorded to date, a common mistletoe (Dendrophthoe pentandra) which can be found on many trees, large and small, in many locations across Singapore. The gregarious caterpillars feed on young leaves of the mistletoe.

Local host plant: Dendropthoe pentandra.

A male in pursuit of a female at a flowering Syzygium plant.

A mating pair of the Painted Jezebel.

Another mating pair of the Painted Jezebel.

The eggs of the Painted Jezebel are laid in a loose cluster on the underside of a leaf of the host plant. Each vase-shaped egg is laid standing at one end or listing to one side with a height of about 1.2-1.3mm. It is pale yellowish with a slightly raised rim surrounding the micropylar sitting atop. The egg turns whitish as it matures.

A female Painted Jezebel ovipositing on a leaf of its local host plant.

A cluster of eggs of the Painted Jezebel.

A close up view of a few eggs of the Painted Jezebel.

The egg takes about 4-5 days to hatch. The caterpillar nibbles away sufficiently large portion of the egg shell to emerge. Each newly hatched has a length of about 2.2mm and has a black head capsule. It has a cylindrical and pale yellow-toned body covered with dorsal, dorso-lateral and lateral rows of fine setae. Each dorsal seta appears to bear a tiny droplet at its distal end.

Newly hatched caterpillars of the Painted Jezebel.

After hatching, the young caterpillars do not bother to devour the rest of the egg shells. They feed on leaf lamina in the vicinity of the oviposition site, resulting in a number of holes on the resident leaf. The body colour turns yellowish green as growth progresses. The growth in this first instar is moderately paced and the body length reaches about 4mm in about 2.5-3 days before the moult to the 2nd instar.

Two view of a 1st instar caterpillar, length 3mm.

A group of 1st instar caterpillars, length 4mm.

Two views of late 1st instar caterpillar, dormant before its moult, length: 3.5mm.

The 2nd instar caterpillar is yellowish brown in body colour. The head capsule is still black as in the 1st instar. There are dorso-lateral and lateral rows of pale yellowish tubercles each of which has a long, fine and whitish seta emanating from it. The dorsal droplet-bearing black setae are still present, but they are now indistinct and dwarfed by the long yellowish dorso-lateral and lateral setae. There is also a small indistinct black anal plate at the posterior end. This instar lasts about 3-4 days with the body length reaching up to 7mm.

A small group of newly moulted 2nd instar caterpillars observed in the field.

Two view of a 2nd instar caterpillar, length: 5mm

The 3rd instar caterpillar resembles the 2nd instar mostly. The seta-bearing tubercles are now in an intense shade of yellow with the setae similarly coloured. The anal plate is larger proportionately and darker in this colour. This instar takes about 3-4 days to complete with body length reaching about 14mm.

Two views of a 3rd instar caterpillar, early in this instar, length: 7mm.

Close-up views showing the droplet-bearing setae on a 3rd instar caterpillar .

A field shot of a group of 3rd instar caterpillars feeding together on the underside of a leaf.

Two views of 3rd instar caterpillar, dormant prior to its moult, length: 12mm.

The appearance of the 4th instar caterpillar is little changed from the 3rd instar. This instar lasts about 3.5-4 days with body length reaching about 22-24mm.

Two views of a 4th instar caterpillar, early in this instar, length: 13.5mm.

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

The 5th and final instar caterpillar resembles the 4th instar caterpillar closely. The black anal plate is larger in proportion compared to those in the early instars. With the head capsule also black in colour, at times it is hard to "make head or tail" of the caterpillar. The 5th instar lasts for 5-7 days, and the body length reaches up to 36-40mm.

Two views of a 5th instar caterpillar, early in this instar, length: 24mm.

Two views of a 5th instar caterpillar, length: 33mm.

A group of final instar caterpillars foundin the field.

Two views of a 5th instar caterpillar, late in this instar, length: 37mm.

On the last day of the 5th instar, the body of the caterpillar shortens with colour decolorised to golden yellow. The fully grown caterpillar ceases feeding and comes to a halt on the underside of a leaf or a stem/stalk on the host plant. Here the caterpillar spins a silk pad and a silk girdle. With its posterior end secured to the silk pad via anal claspers, and the body suspended at the mid-section with the girdle, the caterpillar soon becomes immobile in this pre-pupatory pose.

A pre-pupatory larva of the Painted Jezebel.

Pupation takes place about 0.5-1 day later. The golden yellow pupa secures itself with the same silk girdle as in the pre-pupal stage, but with the cremaster replacing claspers in attaching the posterior end to the silk pad, The pupa has a short black rostrum at the anterior end, short fin-like to spike-like dorsal processes across most body segments and spike-like lateral black processes in the early abdominal segments. A variable number of black streaks can be found in the wing pad. Length of pupae: 24-25mm..

Two views of a pupa of the Painted Jezebel.

Two views of the mature pupa of a female Painted Jezebel.

The mature pupa of a male Painted Jezebel.

After about 6-7 days of development, the pupal skin turns translucent as the development within the pupal case comes to an end. The following day, the adult butterfly emerges from the pupal case.

A female Painted Jezebel emerges from its pupal case.

A newly eclosed male Painted Jezebel clinging onto its empty pupal case.

References:
  • [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 2nd Edition, 2012
  • A Field Guide to the Butterflies of Singapore, Khew S.K., Ink On Paper Communications, 2010.

Text by Horace Tan, Photos by Tan Choon Peng, Benedict Tay, Eng Chuan Goh, Simon Sng, Bobby Mun, Nelson Ong, Federick Ho, Sunny Chir, Khew S K and Horace Tan.

Thursday, May 9, 2013

Random Gallery - Knight

Random Butterfly Gallery
The Knight (Lebadea martha parkeri)



The subspecies parkeri of the Knight that was originally discovered by Norman Parker in Singapore has its submarginal area on the upperside of the hindwing a pale violet-blue. This subspecies is believed to be endemic to Singapore. The south Malaysian subspecies, malayana has the submarginal area of the hindwing a reddish brown. In recent years, this subspecies has been observed in Singapore, and hybrids with the hindwing showing intermediate characteristics between subspecies parkeri and malayana have been observed.

This pristine male Knight (identified by its white wingtips) was feeding on the ripened fruits of the Singapore Rhododendron when I managed to take a number of shots of it with its wings folded upright. Although skittish, it has a weaker flight than the more alert Commander but has the same habit of perching on the top surface of a leaf, just out of reach of the photographer's lens.


Wednesday, May 8, 2013

Random Gallery - Plain Palm Dart

Random Butterfly Gallery
The Plain Palm Dart (Cephrene acalle niasicus)



The Plain Palm Dart is one of two species of the genus Cephrenes found in Singapore. The other one, the Yellow Palm Dart, is an immigrant from the Indo-Australian region. The existence of the Plain Palm Dart was probably overlooked as the male of the species appear very similar to the lookalike Telicota spp. The Plain Palm Dart was added to the checklist as as re-discovery only when the very distinctive female was reliably seen and photographed in Singapore. (See life history article)

The male Plain Palm Dart, with is sharper arrow-like markings on the undersides of its wings, sets is apart from the closely allied Telicota. This individual, shot by ButterflyCircle member Federick Ho, perches in the usual skipper fashion, with its forelegs drawn tightly against its body, and resting only on its mid- and hind legs. Only moderately rare, the Plain Palm Dart is widespread in distribution in Singapore and can be found in urban parks and gardens, mangrove areas and also on the offshore island of Pulau Ubin.