Butterfly Biodata:
Genus: Odontoptilum de Niceville, 1890
Species: angulatum C. Felder, 1862
Sub-species: angulatum C. Felder, 1862
Wingspan of Adult Butterfly: 35-40mm
Caterpillar Local Host Plants: Commersonia bartramia (Malvaceae, Common name: Brown Kurrajong, 山麻树), Talipariti tiliaceum (Malvaceae, Common name: Sea Hibiscus, 黄槿).
Physical Description of Adult Butterfly:
Field Observations of Butterfly Behaviour:
This species is rather rare in Singapore. The adults are usually found near its larval host plants, or when puddling on wet grounds and bird droppings. In Singapore, it may be found in urban wastelands where Commersonia bartramia grows, or in coastal wetlands where Talipariti tiliaceum (Sea Hibiscus) is common. They fly rapidly in bright sunshine in open spaces within forests or wastelands, and visit flowers for nectar. Other sighting locations include various parts of the nature reserves.
Early Stages:
To date only two local host plants (both in Malvaceae family), namely Commersonia bartramia and Talipariti tiliaceum, have been recorded for the Chestnut Angle. The caterpillars of the Chestnut Angle feed on leaves of the host plants. Between feeds, the caterpillars seek safety and concealment in a leaf shelter formed by cutting and folding a leaf fragment along the edge of the leaf.
Local host plant #1: Commersonia bartramia.
Local host plant #2: Talipariti tiliaceum.
The eggs of the Chestnut Angle are laid singly on the upperside of a fully developed leaf of the host plants. The creamy white egg is hemispherical with surface marked with longitudinal ridges running from the pole to the rim of the base. The egg is well concealed in a mass of fine and pale creamy brown setae deposited by the mother butterfly. Each egg has a basal diameter of about 0.9mm.
Two views of an egg of the Chestnut Angle.
Two views of a developing egg of the Chestnut Angle, about 1-2 days prior to hatching.
The egg takes about 5 days to hatch. The young caterpillar emerges by eating away the polar part of the egg shell. The rest of the egg shell is not eaten by the newly hatched which is about 2mm in length. The yellowish orange body is roughly cylindrical in shape and the head capsule is black in color. A prominent, black collar mark is present on the dorsum of the prothorax. Short, white setae are arranged in sub-dorsal and lateral rows on the body surface.
Two views of a newly hatched caterpillar, length: 2mm.
The leaf shelter of a 1st instar caterpillar of the Chestnut Angle.
The newly hatched makes its very first leaf shelter by cutting a near-circular leaf fragment and fold it back on the leaf upper surface. It ventures out of the shelter from time to time to feed on the leaf lamina in the vicinity. As the caterpillar grows, the body assumes a yellowish brown coloration. After reaching about 4mm in about 4 days, the caterpillar moults to the 2nd instar.
Two views of a 1st instar caterpillar, length: 3.1mm.
Two views of a late 1st instar caterpillar, dormant prior to its moult, length: 4mm.
The body of the 2nd instar caterpillar is initially yellowish brown, but turning yellowish with a green undertone as it grows in this stage. The body is covered with numerous tiny and short whitish setae. The head is black with a thin coat of short setae and the prothorax collar mark is still present. The leaf shelter constructed from 2nd instar onwards are typically folded on the underside of a leaf. The caterpillar eat through the floor and ceiling of the leaf shelter at various points, giving the shelter a perforated appearance. This instar lasts about 4 days with the body length reaching about 7mm.
Two views of a 2nd instar caterpillar, newly moulted.
Two views of a 2nd instar caterpillar, length: 5.5mm.
Two views of a late 2nd instar caterpillar, dormant prior to its moult, length: 6.5mm.
The 3rd instar caterpillar closely resembles the 2nd instar caterpillar. The head capsule is still black but bearing a somewhat denser coat of whitish setae. The body colour takes on an increasing whitish tone in this instar which takes about 3-4 days to complete with body length reaching about 11-12mm.
Two views of a 3rd instar caterpillar, newly moulted.
Two views of 3rd instar caterpillar, early in this stage, length: 7.5mm.
Two views of 3rd instar caterpillar, late in this stage, length: 9.9mm.
Two views of a late 3rd instar caterpillar, dormant prior to its moult, length: 10.8mm.
The 4th instar caterpillar has a creamy white body with a yellowish tone. The setae on its black/dark-brown head capsule are now proportionately longer than in the 3rd instar and are white to pale brown in colour. This instar lasts about 7 days with body length reaching about 19-20mm.
Two views of a 4th instar caterpillar, newly moulted.
Two views of a 4th instar caterpillar, length: 16mm.
Two views of a late 4th instar caterpillar, dormant prior to its moult.
Leaf shelter of a 4th instar caterpillar of the Chestnut Angle found in the field.
A close-up view of the upper exterior of the leaf shelter of a 4th instar caterpillar of the Chestnut Angle. Noted the perforated leaf surface.
The 5th instar caterpillar has similar body appearance as in the 4th instar but the colour of the dense coat of setae head has become wholly pale brown. The 5th instar lasts for about 10-11 days, and the body length reaches up to 35-37mm.
Two views of a 5th instar caterpillar, newly moulted.
Two views of a 5th instar
caterpillar, early in this stage, length: 20.5mm.
Two views of a
5th instar caterpillar, later in this stage, length:36mm.
A close-up view of the under exterior of the leaf shelter of a 5th instar caterpillar of the Chestnut Angle. Noted the perforated leaf surface.
A pre-pupa of the Chestnut Angle.
Two views of a pupa of the Chestnut Angle.
Two views of another pupa of the Chestnut Angle with less spots on the thorax.
Two views of a mature pupa of the Chestnut Angle.
A newly eclosed Chestnut Angle resting next to its pupal case.
References:
Genus: Odontoptilum de Niceville, 1890
Species: angulatum C. Felder, 1862
Sub-species: angulatum C. Felder, 1862
Wingspan of Adult Butterfly: 35-40mm
Caterpillar Local Host Plants: Commersonia bartramia (Malvaceae, Common name: Brown Kurrajong, 山麻树), Talipariti tiliaceum (Malvaceae, Common name: Sea Hibiscus, 黄槿).
Physical Description of Adult Butterfly:
The forewing termen is sinuous, and the hindwing prominently stepped at vein 7. The upperside is chestnut-brown with a complex, cryptic pattern of white striae in the hindwing. The forewing has a dark sub-discal band, a crescentic hyaline spot in space 2, and a smaller spot above it near the base of space 3. In addition, two apical spots can be found in spaces 7 and 8. Hindwing has elongated tornal cilia. The male possesses a tuft of white hairs on the fore coxae, and the female has a thick anal tuft on the abdomen. The underside is predominantly whitish in the hindwing.
Field Observations of Butterfly Behaviour:
This species is rather rare in Singapore. The adults are usually found near its larval host plants, or when puddling on wet grounds and bird droppings. In Singapore, it may be found in urban wastelands where Commersonia bartramia grows, or in coastal wetlands where Talipariti tiliaceum (Sea Hibiscus) is common. They fly rapidly in bright sunshine in open spaces within forests or wastelands, and visit flowers for nectar. Other sighting locations include various parts of the nature reserves.
Early Stages:
To date only two local host plants (both in Malvaceae family), namely Commersonia bartramia and Talipariti tiliaceum, have been recorded for the Chestnut Angle. The caterpillars of the Chestnut Angle feed on leaves of the host plants. Between feeds, the caterpillars seek safety and concealment in a leaf shelter formed by cutting and folding a leaf fragment along the edge of the leaf.
The eggs of the Chestnut Angle are laid singly on the upperside of a fully developed leaf of the host plants. The creamy white egg is hemispherical with surface marked with longitudinal ridges running from the pole to the rim of the base. The egg is well concealed in a mass of fine and pale creamy brown setae deposited by the mother butterfly. Each egg has a basal diameter of about 0.9mm.
The egg takes about 5 days to hatch. The young caterpillar emerges by eating away the polar part of the egg shell. The rest of the egg shell is not eaten by the newly hatched which is about 2mm in length. The yellowish orange body is roughly cylindrical in shape and the head capsule is black in color. A prominent, black collar mark is present on the dorsum of the prothorax. Short, white setae are arranged in sub-dorsal and lateral rows on the body surface.
The newly hatched makes its very first leaf shelter by cutting a near-circular leaf fragment and fold it back on the leaf upper surface. It ventures out of the shelter from time to time to feed on the leaf lamina in the vicinity. As the caterpillar grows, the body assumes a yellowish brown coloration. After reaching about 4mm in about 4 days, the caterpillar moults to the 2nd instar.
The body of the 2nd instar caterpillar is initially yellowish brown, but turning yellowish with a green undertone as it grows in this stage. The body is covered with numerous tiny and short whitish setae. The head is black with a thin coat of short setae and the prothorax collar mark is still present. The leaf shelter constructed from 2nd instar onwards are typically folded on the underside of a leaf. The caterpillar eat through the floor and ceiling of the leaf shelter at various points, giving the shelter a perforated appearance. This instar lasts about 4 days with the body length reaching about 7mm.
The 3rd instar caterpillar closely resembles the 2nd instar caterpillar. The head capsule is still black but bearing a somewhat denser coat of whitish setae. The body colour takes on an increasing whitish tone in this instar which takes about 3-4 days to complete with body length reaching about 11-12mm.
The 4th instar caterpillar has a creamy white body with a yellowish tone. The setae on its black/dark-brown head capsule are now proportionately longer than in the 3rd instar and are white to pale brown in colour. This instar lasts about 7 days with body length reaching about 19-20mm.
The 5th instar caterpillar has similar body appearance as in the 4th instar but the colour of the dense coat of setae head has become wholly pale brown. The 5th instar lasts for about 10-11 days, and the body length reaches up to 35-37mm.
On the last day of the 5th instar, the body decolorises to a pale shade of creamy white. The
caterpillar ceases feeding and confines itself to the leaf shelter. The pre-pupatory larva prepares for the pupal phase with a series of silk construction work with the main pieces being
a silk girdle across the
dorsum of its early abdominal segments, and a silk pad on the substrate at its posterior end. Soon the pre-pupatory larva becomes
dormant in its leaf shelter. Pupation takes place about 1 day later.
The girdled pupa is secured with its cremaster attached to the silk pad on the substrate. It has a knobbed rostrum and two small, orange-coloured, ear-like appendages at the leading edge of the mesothorax. The body is creamy white with a pale green undertone. There
are black spots arranged in neat symmetrical layout on the body segments. Thin, black striae adorn the wing pad. Length of pupae: 17-19.5mm.
After about 7 days of pupal
development, the pupa turns dark, especially so in the wing pad and thorax areas. The following day, the adult butterfly emerges from the pupal case.
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, 2nd Edition, 2015.
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