23 June 2024

Life History of the Malayan Jester

Life History of the Malayan Jester (Symbrenthia hippoclus selangorana)


Butterfly Biodata:
Genus: Symbrenthia Hübner, 1819
Species: hippoclus Cramer, 1779
Sub-species: selangorana Corbet, 1948
Wingspan of Adult Butterfly: 21-22mm
Caterpillar Local Host Plant: Pipturus argenteus (Urticaceae, common name: Australian Mulberry)


A male Malayan Jester puddling on a wet ground.



Physical Description of Adult Butterfly:
On the upperside, the wings are black with orange bands. The forewing has a broad sub-apical band and a shorter outer sub-apical band. On the underside, the wings are pale orange with numerous reddish brown lines and spots. A narrow reddish brown band runs from mid-termen of the forewing to the mid-dorsum of the hindwing. On the forewing, the post-discal spot in space 3 is prominent and pale pinkish in colour. On the hindwing, there is a series of pale pinkish post-discal spots, and a prominent blue crescent-shaped sub-marginal spot in space 3. The hindwing also features a short pointed tail at vein 4.

The upperside view of a female Malayan Jester.

The upperside view of a male Malayan Jester.

A male Malayan Jester puddling on a wet ground.

Field Observations of Butterfly Behaviour:
Malayan Jester was first discovered in 2012 in the western part in Singapore. It has since established a foothold in Singapore with increasingly regular appearances in recent years in places such as the Southern Ridges, Dairy Farm Nature Park, Rifle Range Nature Park, Lornie Park Connector, Bukit Brown and Windsor Nature Park. The adults are skittish. They have been observed to take nectar from flowers of plants such as Leea indica, Leea rubra and Singapore Rhododendron. Males have also been seen puddling on damp forest paths.




Early Stages:


A video clip showing various stages of the life cycle of the Malayan Jester.

Pipturus argenteus (Australian Mulberry) is the only local host plant recorded so far for the Malayan Jester. The same plant is also the larval host plant for Hypolimnas anomala anomala (Malayan Eggfly) and Megisba malaya sikkima (Malayan).

Local host plant: Pipturus argenteus (Australian Mulberry).

Eggs of the Malayan Jester are laid in a large cluster on the underside of a leaf of the host plant. Each egg is globular in shape and pale yellowish in colour. Ten ridges run from the micropylar at the top to the base where the egg is adhered to the leaf surface. Numerous inconspicuous striations runs horizontally between these vertical ridges. Each egg has a diameter of about 0.6-0.7mm, and a height of about 0.7mm.

A cluster of 85 eggs of the Malayan Jester.

Close-up views of eggs of the Malayan Jester. Left: top view; Right: lateral view.

Maturing eggs of the Malayan Jester.

High rates of parasitism are typically observed for egg clusters recorded in the field, with tiny parasitoid wasps being the culprit. If not infected, an egg of the Malayan Jester takes about 5-6 days to hatch. The young caterpillar emerges by eating a sufficiently large part of the egg shell. The newly hatched is about 1.9-2.0mm in length and it has a black head capsule and a cylindrical and pale yellowish body covered with rows of long black setae (hair) dorsally and dorso-laterally. The caterpillars of the Malayan Jester are gregarious in all five instars of the life cycle.

Lateral view of a cluster of fully developed eggs, with a newly hatched already made the exit earlier.

A group of newly hatched Malayan Jester caterpillars, already consumed some leaf lamina nearby.

Two views of an early 1st instar caterpillar of the Malayan Jester, length: 2mm.

The caterpillars feed on the mature leaves of the host plant. In the first instar, as growth progresses, the body of the caterpillars quickly turns yellowish brown with a strong dark greenish undertone. After reaching about 4mm in about 3 days, the caterpillars moult to the 2nd instar.

Two views of a 1st instar caterpillar of the Malayan Jester, length: 2.9mm.

A group of 1st instar caterpillars of the Malayan Jester, length: 2.9-3mm.

Two views of a late 1st instar caterpillar of the Malayan Jester, dormant prior to its moult.

The body of the 2nd instar caterpillar is yellowish brown to dark brown with a greenish undertone. The head capsule is black with no cephalic horns. Moderately long tubercles, each of which is endowed with dendritic spines and setae, run along the length of the body. On each side of the body, there are three series of such tubercles: one occurs dorso-laterally, another laterally and the last sub-spiracularly. This instar lasts about 3 days with the body length reaching about 5.5mm.

Two views of a 2nd instar caterpillar of the Malayan Jester, early in this stage, length: 3.6mm.

Two views of a 2nd instar caterpillar of the Malayan Jester, length: 5.2mm.

A group of 2nd instar caterpillars of the Malayan Jester, length: 5-5.2mm.

Two views of a late 2nd instar caterpillar of the Malayan Jester, dormant prior to its moult.

The 3rd instar caterpillar resembles the 2nd instar caterpillar closely, with the same three series of tubercles. These tubercles and associated dendritic spines are proportionately longer (than those in the 2nd instar) and dark brown in coloration, except for some of the sub-spiracular tubercles and spines which are whitish. This instar takes about 3 days to complete with body length reaching about 10-11mm.

A 3rd instar caterpillar of the Malayan Jester, length: 7mm.

Two views of a 3rd instar caterpillar of the Malayan Jester, length: 8mm.

A group of 3rd instar caterpillars of the Malayan Jester, feeding together along the leaf edge, length: 9-9.5mm.

Two views of a late 3rd instar caterpillar of the Malayan Jester, dormant prior to its moult, length: 8mm.

The 4th instar caterpillar closely resembles the 3rd instar caterpillar, but with much darker brown coloration on the body segments. Almost all of the sub-spiracular tubercles and spines appear whitish to pale yellowish. In this instar, the caterpillars have the habit of cutting the mid-rib and major side-ribs of the leaf. The 4th instar lasts about 2.5-3 days with the body length reaching about 17-18mm.

Two views of a 4th instar caterpillar, early in this stage, length: 10mm.

Two views of a 4th instar caterpillar of the Malayan Jester, length: 14.8mm.

A group of 4th instar caterpillars of the Malayan Jester. Note the cut mid-rib and side ribs to the right of the picture.

Two views of a late 4th instar caterpillar of the Malayan Jester, dormant before its moult.

The 5th (and final) instar caterpillar is similar to the 4th instar caterpillar but there are some noticeable changes. The colour of the three series of tubercles and spines is now variable with some specimens featuring all black coloration and others with a mix of pale yellowish and black coloration. Small white spots now adorn the space between the sub-spiracular tubercles. Numerous smaller, obscure whitish specks and short setae occur on the body surface. A few white streaks also appear in the space between the thoracic segments.

A 5th instar caterpillar of the Malayan Jester, early in this instar, length: 18mm.

Two views of a 5th instar caterpillar of the Malayan Jester, with pale yellowish tubercles and spines, length: 27.5mm.

Two views of a 5th instar caterpillar of the Malayan Jester, with black tubercles and spines, length: 31.5mm.

A group of 5th instar caterpillars of the Malayan Jester on the underside of a partly-eaten leaf.

The 5th instar caterpillars have the habit of biting the petiole of a leaf and folding the leaf to make a simple leaf shelter. They rest in the shelter between feeding sessions on nearby leaves.

Three leaf shelters of the Malayan Jester observed in the field.

A look into a leaf shelter of 5th instar caterpillars of Malayan Jester.

The 5th instar lasts for about 4 days, and the body length reaches up to 27-28mm. On the last day, the body becomes shortened and the caterpillar ceases feeding and wanders around. Eventually it stops at a spot on the underside of a stem or twig and spins a silk pad from which it hangs vertically to take on the pre-pupatory pose.

A pre-pupa of the Malayan Jester.

Pupation takes place about 0.5 day after the caterpillar assumes the J-shaped hanging posture. The pupa suspends itself from the silk pad with no supporting silk girdle. The pupa is either pale brown to dark brown in coloration. The dorsum of the thoracic segments is raised to form a tall ridge at the mesothorax. There are two black streaks and two black spots on the ventral side of the thorax. At the anterior end, there are two short cephalic horns. Length of the pupa: 17-18.5mm.


Video: A Malayan Jester caterpillar turning into a pupa.

A group of pupae of the Malayan Jester.

Three views of a pupa of the Malayan Jester.

Three views of a fully developed pupa of the Malayan Jester.

After about 4-6 days of development, the pupal skin of the mature pupa turns translucent and the whole pupa becomes mostly darker brown. The orange bands on the forewings can also be seen in the wing pads at this stage. The eclosion event takes place the next day.


Video: A female Malayan Jester emerges from its pupal case.

Newly eclosed Malayan Jester resting on its pupal case. Left: female; Right: male.

References:
  • [C&P5] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury;  G. and N.  van der Poorten (Eds.),  5th Edition, Malayan Nature Society (2020).
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 2nd Edition, 2012.
  • A Field Guide to the Butterflies of Singapore, Khew S.K., Ink On Paper Communications, 2nd Edition, 2015.
Text by Horace Tan, Photos by Frederick Ho, Loh Mei Yee, Khew S K, Jonathan Soong and Horace Tan, Videos by Loh Mei Yee and Horace Tan.

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