Saturday, February 15, 2014

Butterfly of the Month - February 2014

Butterfly of the Month - February 2014
The Hieroglyphic Flat (Odina hieroglyphica ortina)



February 2014 heralded the Year of the Horse in the Chinese zodiac calendar. Unlike last year, when it was uncharacteristically wet for February, this year's weather was quite typical of the dry season, as the North East Monsoon winds waned and the rains that we experienced in the last few months of December 2013 suddenly dried up. Despite the cool north-easterly winds bringing temperatures to a low in early 2014, the exceptionally dry weather began to take its toll on the plants and greenery all around the island. Even in the forests, the leaf litter was particularly brittle and dry whilst the trees and shrubbery appeared limp and listless.



The National Environment Agency warned of imminent haze and poor air quality as the number of hotspots in neighbouring Indonesia increased alarmingly. Typical of the way the Indonesian farmers clear their agriculture land, it has been almost a yearly affair that the wanton burning of forests to clear land for farming will send plumes of choking smoke over to Malaysia and Singapore. The Indonesian authorities appear almost powerless to stop this pollution and environmental abuse as fires burn uncontrollably in their country.



I always wonder how much more of this can Mother Nature take, before she unleashes her wrath at those people who insist on destroying nature around them - solely for monetary gain and little else. We share this planet with the flora and fauna around us, and humans, being the most intelligent of all the creatures that inhabit our Earth, is by far also the greatest destroyers and consumers of our natural resources.



Over here in Singapore, the first two months of the year saw a curious number of unprecedented breakdowns in the MRT system. Some were reported to be due to "human error" and is some cause for concern, as the system has been running for so many years with very few breakdowns in the early years of the system, only to see "human errors" creeping into the operations? There appears to be some systemic issues that the SMRT needs to get a handle on these days before things get any worse.



A number of high profile fatal accidents at construction sites also plagued the industry. Usually, upon investigations, the conclusion is often that the accident could have been avoided, or prevented. Are contractors throwing caution to the wind as far as safety is concerned, for the sake of economic returns? Or is the pressure of ever-tighter deadlines and schedules forcing the workers to take short cuts just to speed up the work? Are developers imposing unrealistic deadlines on their projects, so that they can start getting returns on their investments?  Whatever the reasons are, when a worker dies at the site, someone, somewhere else in the world has lost a son, a father or a husband. Let us remind ourselves that it is not just a statistic on a piece of paper.



This month, we feature a Hesperiidae, commonly called Skippers from the subfamily Pyrginae, which are collectively called "Flats".  This subfamily features species that are robust-bodied, fast-flying butterflies that tend to stop with their wings opened flat, even when feeding or sunbathing. February's Butterfly of the Month is the Hieroglyphic Flat (Odina hieroglyphical ortina).  



Skippers are usually drab, brown coloured butterflies with large eyes and fat bodies. To the uninitiated, they are usually mistaken for moths. However, there are exceptions to these often unappreciated butterflies like the Hieroglyphic Flat, which are relatively more colourful and eye-catching. Over in South America, the Hesperiids are even more spectacular - with iridescent blues and long tails!



The male Hieroglyphic Flat has yellow-orange patches framed by thick black lines on both wings. Females are paler yellow and appear more faded in colour than the male. The underside markings are similar to the upperside, but often paler in colour. The abdomen is striped with black. There are obscure arrow-shaped marginal markings on the upperside of the forewings near the apical area.



This skipper is quite distinctive-looking and cannot be mistaken for any other butterfly species in Malaysia or Singapore. The cryptic patterns are reminiscent of the camouflage paintwork of a German Messerschmitt ME Bf 109 fighter plane in Hitler's desert campaign during World War II. I've often been asked what an ME Bf 109 with desert camouflage looks like, so here it is! Can you see the resemblance? But whether the Hieroglyphic Flat's colours provide it with any form of camouflage in our forests is debatable.



The Hieroglyphic Flat is a fast flyer and in some locations, two or more individuals are sometimes observed dog-fighting at the tree tops, vying for the best perch to sunbathe themselves. A common trait with most of the "Flat" species is that they will fly around rapidly, then perch on the undersides of leaves with their wings opened flat to rest or hide from intruders.




In the forests, the species is often observed puddling on bird droppings. It will repeatedly return to the bird dropping even when disturbed, and then feed greedily, giving a good opportunity to photograph it. It has occasionally been seen puddling at sandy streambanks and footpaths in the forests as well. The Hieroglyphic Flat has a wide distribution and can be seen at urban parks and gardens as well as in the forested nature reserves.



The early stages of this skipper has been recorded and documented here. The caterpillar host plant is Erycibe tomentosa, which is a woody climber and can locally be found on hedges, edges of forests and sides of forest trails, in areas such as the Central Catchment Area and Southern Ridges.



Text by Khew SK : Photos by Sunny Chir, Chng CK, Khew SK, Koh CH, Loke PF, Nelson Ong & Horace Tan


Thursday, February 13, 2014

Butterflies Galore! : Common Birdwing

Butterflies Galore!
The Common Birdwing (Troides helena cerberus)



The Common Birdwing is one of the Troides spp that is a CITES-protected species (the genus Troides is listed in Appendix II of protected species). Although it is not rare in South East Asia, and in locations where its caterpillar host plants are cultivated, the species can actually be common, the CITES protection is probably to protect this large and showy butterfly from being traded to extinction.

The Common Birdwing is a large and beautiful butterfly with its black and yellow wings. It is believed that the aposematic colouration is a display to predators that it is distasteful and should be avoided. Its caterpillar host plant is Aristolochia acuminata which this species shares with the Common Rose (Pachliopta aristolochiae asteris). Here, a male Common Birdwing is feeding on the nectar of the Hibiscus flower.

Wednesday, February 12, 2014

Butterflies Galore! : Common Tiger

Butterflies Galore!
The Common Tiger (Danaus genutia genutia)



The flowers, stems and pods of the Rattlebox Pea (Crotalaria retusa) often attract species of the Danainae sub-family to feed on them. Whilst there are no apparent "food source" for the butterflies to feed on, these Danainae actually use their sharp tarsal "claws" on their legs to scratch the surface of the plant, flower or pod which then exudes a fluid that the butterflies feed upon. There must be some chemical compound that the butterflies are attracted to. At times, several butterflies can be found feeding on the same plant.

This male Common Tiger is feeding on the secretions of the Rattlebox Pea flower bud after scratching the surface of the bud. This shot was taken by ButterflyCircle member Simon Sng at Pulau Ubin's Butterfly Hill, where the Rattlebox Pea plants are cultivated along the roadside.

Monday, February 10, 2014

Butterflies Galore! : Branded Imperial

Butterflies Galore! 
The Branded Imperial (Eooxylides tharis distanti)



This pretty long-tailed Lycaenid is relatively common in Singapore's forested areas, usually in the vicinity of its caterpillar host plant, Smilax bracteata, an invasive forest weed. The butterfly is bright orange on the underside, with a black-and-white tornal area on the hindwing, and a long white tail at vein 2. It flies with a short, hopping flight, and prefers the shady forest understorey. Quite often, several individuals are observed together.

This Branded Imperial was shot by ButterflyCircle member Mark Wong last weekend. It shows the butterfly perched on the top of a leaf, resting in the shade.

Saturday, February 8, 2014

Life History of the Malayan Five Ring

Life History of Malayan Five Ring (Ypthima horsfieldi humei )


Butterfly Biodata:
Genus: Ypthima Hübner, 1818
Species: horsfieldi Moore, 1884
Subspecies: humei Elwes & Edwards, 1893
Wingspan of Adult Butterfly: 30-40mm
Caterpillar Local Host Plant: Axonopus compressus (Poaceae, common names: Wide-leaved Carpet Grass, Cow Grass), Ottochloa nodosa (Poaceae), Kyllinga nemoralis (Cyperaceae, common name: White Kyllinga).




Physical Description of Adult Butterfly:
On the upperside, the wings are dull brown in the female and greyish brown in the male. Both sexes have a large yellow-ringed ocellus in space 2 of the forewing, and two smaller yellow-ringed ocelli in spaces 2 and 3 of the hindwing. The male has a broad strip of greyish black brand in the forewing. On the underside, both wings are pale greyish to bluff brown against a whitish background, and are traversed by numerous fine dark brown striae. The forewing has a large, bi-pupilled, yellow-ringed subapical ocellus. The hindwing has five yellow-ringed ocelli in spaces 1b, 2, 3, 5 and 6. The pair of ocelli in spaces 2 and 3 are well separated, and the one in space 1b consists of two conjoined spots.

Upperside view of a female Malayan Five Ring.

Upperside view of a male Malayan Five Ring.


Field Observations of Butterfly Behaviour:
The Malayan Five Ring is common in the nature reserves and surrounding vegetated areas. Adults are typically sighted flying low among vegetation in and around grassy patches. As with other Satyrinae members, the adults fly in an erratic and jerky manner. The adults visits flowers for nectar and sun-bathe with fully opened wings in sunny conditions.

Early Stages:
Thus far, three common grass species have been recorded as larval hosts for the Malayan Five Ring. The caterpillars feed on leaves of the host plant, and have been observed to forcefully ejecting their frass pellets, a larval habit rarely seen outside the skipper/flat families. They tend to rest lengthwise on the underside of a leaf during pauses between feeds.

Host plant #1: Axonopus compressus.

Local host plant #2: Ottochloa nodosa.

Host plant #3: Kyllinga nemoralis.

A mating pair of Malayan Five Ring.

The eggs are laid singly on the underside of a grass blade of the host plant or on other small plants or objects in the vicinity of the host plants. Each egg is nearly globular (about 0.9mm in height, 0.8-0.85mm in diameter) and pale translucent with a light bluish tinge. It appears to be smooth to the naked eyes, but faintly sculptured with a very fine polygonal grid when viewed with a macro lens.

A mother Malayan Five Ring laying an egg on a dry plant part among leaf litter.

Two views of an egg of the Malayan Five Ring.

Two views of a mature egg with the head faintly visible through the egg shell.

The egg takes about 4.5 days to mature. The young caterpillar nibbles away a portion of the egg shell to exit and then proceeds to devour the rest of the egg shell. It has a whitish, cylindrical body with small pink patches occurring dorsally and laterally. The initial body length is about 2mm. The body is covered with dorso-lateral and lateral rows of long setae. At the posterior end, there is a short pair of backward-pointing processes. Its pale brownish head features a few setae, a pair of short and rounded "horns" and a few lateral protuberances.

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

As a result of its leaf diet, the 1st instar caterpillar soon takes on a strong greenish undertone. The first instar lasts about 4 days with the body length increases to about 4-4.5mm.

Two views of a 1st instar caterpillar, length: 2.8mm.

Two views of a 1st instar caterpillar, length: 4mm.

Two views of a late 1st instar caterpillar, dormant prior to its moult, length: 4.3mm.

In the 2nd instar, the cephalic "horns" are less distinct and the two anal processes proportionately longer and pointed. The head is now pale translucent green and featuring a number of small, whitish tubercles. The body color is pale yellowish green and adorned with rows of numerous, whitish, minute tubercles, each with a single seta emanating from it. The 2nd instar lasts about 4-4.5 days with the body length reaches about 6.5mm.

Two views of a 2nd instar caterpillar, early in this stage, 4.3mm.

Two views of a 2nd instar caterpillar, length: 6mm.

Two views of a late 2nd instar caterpillar, dormant prior to its moult, length: 6.5mm.

The 3rd instar caterpillar mostly resembles its former self in the 2nd instar. This stage takes 4.5-5 days to complete with body length reaching about 10mm.

Two views of a newly moulted 3nd instar caterpillar.

Two views of a 3nd instar caterpillar, length: 9.5mm.

Two views of a late 3nd instar caterpillar, dormant prior to its moult, length: 9mm.

Again, there is no obvious change in the appearance of the caterpillar from the 3rd to the 4th instar. This penultimate instar lasts about 6-7 days with body length reaching 15-16mm.

Two views of a newly moulted 4th instar caterpillar, length: 8.5mm.

Two views of a 4th instar caterpillar, length: 13mm.

Two views of a late 4th instar caterpillar, dormant prior to its moult, length: 14.5mm.

Malayan Five Ring caterpillars in the act of catapulting frass pellets.

The next moult brings the caterpillar to its 5th and final instar. Now the caterpillar has a strongly banded appearance with a number of narrow whitish bands running lengthwise. There is a distinct whitish sub-spiracular band and the spiracles are black. Pairs of small black patches appear on the dorsum of several mid-body segments. The head capsule has additional small brown to black patches occurring on the front and laterally. As growth progresses, some specimens change from a greenish appearance (green form) to a pinky brown appearance (brown form). In a period of 8-9 days, the body grows to a maximum length of about 32-35mm.

Two views of a newly moulted 5th instar caterpillar, length: 13.5mm.

Two views of a 5th instar caterpillar, green form, length: 17mm.

Two views of a 5th instar caterpillar, brown form, length: 22.5mm.

Two views of a 5th instar caterpillar, green form, length: 24mm.

Toward the end of the 5th instar, the body gradually shrinks in length. Finally the caterpillar finds a spot on the underside of a leaf blade or a stem to spin a silk pad. It then secures itself there via its anal end, and assumes its upside-down pre-pupatory pose.

Two prep-pupae of Malayan Five Ring. Left: green form; Right: brown form.

After one day as a pre-pupa, pupation takes place. The slender pupa has a beige brown ground colour with numerous small brown/black patches. There are two low transverse dorsal ridge on abdominal segments 3 and 4, and a longitudinal dorsal ridge on the thorax. Length of pupae: 11.5-12mm.

A Malayan Five Ring caterpillar moults to its pupal stage.

Three views of a pupa of Malayan Five Ring.

After 7 days of development, the pupa becomes darkened in color, and the ringed-spot on the forewings can now be seen through the pupal skin in the wing pads. The next day the eclosion event takes place with the adult butterfly emerges to start the next phase of its life cycle.

Three views of a mature pupa of Malayan Five Ring.

A Malayan Five Ring butterfly emerges from its pupal case.

A newly eclosed Malayan Five Ring.

References:
  • [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society, 1992.
  • 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 Benedict Tay, Jayne Kok, Simon Sng, Federick Ho, Khew SK and Horace Tan

Wednesday, February 5, 2014

Butterflies Galore! : Cruiser

Butterflies Galore!
The Cruiser (Vindula dejone erotella)



The Cruiser is a good example of sexual dimorphism in butterflies. This is phenomenon where the male and female of a species appear distinctly different from each other. Males of the Cruiser are more common, and often encountered puddling at sandy streambanks and forest footpaths. Their bright orange colour and large size make them conspicuous in the forested areas of the nature reserves. More pictures of the Cruiser can be found here.

The female, however, is a pale greenish-grey with a prominent white post-discal band edged with a dark zig-zag pattern, running across both wings. The orange ocelli on the hindwings are large and prominent. The females rarely puddle, and prefer feeding on flowers, like in this shot by ButterflyCircle member Nelson Ong, where the butterfly is feeding on the flowers of the Mile-A-Minute creeper.

Tuesday, February 4, 2014

Butterflies Galore! : Tailed Jay

Butterflies Galore!
The Tailed Jay (Graphium agamemnon agamemnon)



This "Swallowtail" of the genus Graphium is relatively common in urban areas where its host plants are cultivated. Its polyphagous caterpillars feed on a variety of road side trees like the Chempaca and Ashoka trees, as well as the Soursop which is sometimes cultivated in urban gardens. The upperside of the butterfly is an attractive black with emerald green spots on both wings. See more photos of this species here.

The Tailed Jay is a fast flyer with an erratic flight. But occasionally, it can be encountered when resting in the shade with its wings folded upright, as was shot here by young ButterflyCircle member Jonathan Soong, or sunbathing with its wings opened flat to show its impressive upperside. Females have longer tails than the males.