Butterfly Biodata:
Genus: Junonia Hübner, 1819
Species: hedonia Linnaeus, 1764
Subspecies: ida Cramer, 1775
Wingspan of Adult Butterfly: 55-60mm
Caterpillar Local Host Plants: Ruellia repens (Acanthaceae), Hemigraphis reptans (Acanthaceae)
A Chocolate Pansy displaying its upperside.
A Chocolate Pansy giving us a view of its underside.
Physical Description of Adult Butterfly:
Above, the wings are orangy brown with several indistinct but darker brown bands traversing from the costa towards the dorsum. There are two cell spots on the forewing and a prominent series of reddish brown post-discal ocelli on the hindwing. A much less prominent series of post-discal ocelli is also present on the forewing. Underneath, both fore- and hindwings are in duller brown but each has a dark stripe traversing from the costa to the dorsum. The stripes appear to be continuous across the two wings. A large white spot is present next to the stripe in space 7 of the hindwing. A post-discal series of ocelli is present on both wings, and these ocelli are yellowish brown on pristine specimens.
A Chocolate Pansy visiting flowers.
An adult Chocolate Pansy taking up its position on a leaf.
Field Observations of Butterfly Behaviour:
This species is rather common across multiple habitats in Singapore, with ubiquitous presence in nature reserves as well as urban and suburban areas. It flies in the usual gliding manner of the Junonia spp. and typically several individuals can be seen together in one location. Under sunny conditions, they have a habit of opening their wings wide to sunbathe while resting on a perch.
Early Stages:
The caterpillars of the Chocolate Pansy feed mainly on leaves of the two recorded local host plants, Ruellia repens and Hemigraphis reptans. Both plants belong to the Acanthaceae family, and occur as widespread weeds in Singapore. It is likely that more members of this family serve as the larval food plants for Chocolate Pansy.
Local host plant #1: Hemigraphis reptans.
Local host plant #2: Ruellia repens.
A mating pair of the Chocolate Pansy.
A mother Chocolate Pansy laying an egg on the underside of a leaf of Hemigraphis reptans.
The eggs of the Chocolate Pansy are laid singly on the young leaves or shoots of the host plants. The greenish egg is somewhat globular in shape but with a blunt top. Twelve raised ridges run from this top end to the base of the egg. Each egg has a diameter of about 0.75mm.
Two views of an egg of the Chocolate Pansy. Diameter: 0.75mm.
Two views of a mature egg of the Chocolate Pansy.
The egg takes about 3 days to hatch. The young caterpillar emerges by eating away part of the egg shell, and then proceeds to eat the rest of the egg shell from the outside. The initial length of the newly hatched is about 1.5mm. The cylindrical and pale yellowish body is covered with many small tubercles. Long dark setae emanate from those tubercles occurring dorso-laterally, and long whitish setae occur sub-spiracularly. The head capsule is pale yellowish with two large lateral dark patches.
Two views of a newly hatched caterpillar, length: 1.5mm.
The 1st instar caterpillar feeds on the lamina of young leaves and grows rapidly. After reaching about 3mm in 1.5 days, the caterpillar moults to the 2nd instar.
Two views of a 1st instar caterpillar, length: 2.8mm.
Two views of a 1st instar caterpillar, late in this stage, length: 3mm.
The body of the 2nd instar caterpillar is yellowish brown mainly and is darker brown on the dorsum. Moderately long and branched brownish processes run along the length of the body. Fine setae emanate from these processes and from other small tubercles on the body surface. The head capsule is yellowish to orangy brown and featuring two small dark brown lateral patches. This instar lasts about 2 days with the body length reaching about 5mm.
Two views of a 2nd instar caterpillar, newly moulted, length: 2.5mm
Two views of a 2nd instar caterpillar, late in this stage, length: 4.5mm
The 3rd instar caterpillar has proportionately longer dorso-lateral and lateral processes. The body is mostly dark brown to black, except for the posterior end which is yellowish to orangy brown. This instar takes about 2 days to complete with body length reaching about 8.5mm.
Two views of a 3rd instar caterpillar, newly moulted, length: 4.5mm.
Two views of a 3rd instar caterpillar, late in this stage, length: 8mm.
Two views of a 3rd instar caterpillar, about to moult. Inset: head capsule.
The 4th instar caterpillar closely resembles the 3rd instar caterpillar, except for the proportionately longer processes and the change to an orange base color for the head capsule. The body color is almost entirely black except for a short section of yellowish brown at the posterior end. A fair number of small white specks appear on the body surface. The 4th instar lasts 2-2.5 days with the body length reaching about 12mm.
Two views of a 4th instar caterpillar, early in this stage, length: 9mm.
Two views of a 4th instar caterpillar, late in this stage, length: 11mm.
Two views of a 4th instar caterpillar, about to moult, length: 11.5mm.
The 5th (and penultimate) instar caterpillar is similar to the 4th instar caterpillar.One discernible difference is the presence of a dense set of moderately long fine setae covering the entire body surface. This instar lasts for 2.5-3 days, and the body length increases rather dramatically and reaches up to 23.5mm.
A 5th instar caterpillar, newly moulted, length: 11mm.
Two views of a 5th instar caterpillar, early in this stage, length: 12.5mm. Inset: head capsule.
Two views of a 5th instar caterpillar, about to moult, length: 22mm.
The 6th (and final) instar caterpillar is similar to the 5th instar caterpillar but has an even denser carpet of whitish fine setae on the body surface. Upon closer examination, pitch black triangular patches, one to each body segment, can be discerned against a lighter shade of black for the body base colour. The head capsule is bright orange and has two black patches on both sides of the "face".
Two views of a 6th instar caterpillar, early in this stage, length: 23mm.
Two views of a 6th instar caterpillar, length: 36mm.
The 6th instar lasts for 4-4.5 days, and the body length reaches up to 40mm. The caterpillar ceases feeding and wanders around. Eventually it stops at a spot on the underside of a leaf, young shoot/stem and spins a silk pad from which it hangs vertically to take on the pre-pupatory pose.
A pre-pupa of the Chocolate Pansy.
The pupation event of a Chocolate Pansy caterpillar.
Pupation takes place about 0.5 days later. The pupa suspends itself from the silk pad with no supporting silk girdle. It is entirely greyish brown with a series of dorso-lateral pairs of short and pointed processes, one pair to each segment. The dorsum is sharply raised at the mesothorax. Black markings are also featured in the wing pads. Length of pupae: 18-19mm.
Three views of a pupa of the Chocolate Pansy.
Three views of a mature pupa of the Chocolate Pansy.
After about 5 days of development, the pupal skin of the mature pupa turns translucent and the pupa turns dark brown as a result. Patches of orangy brown can also be noticed in the wing pad. The adult butterfly emerges from the pupa the next day.
The eclosion event of a Chocolate Pansy caterpillar.
A newly eclosed Chocolate Pansy resting on its pupal case.
References:
- [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
- A Field Guide to the Butterflies of Singapore, Khew S.K., Ink On Paper Communications, 2010.
Text by Horace Tan, Photos by Simon Sng, Federick Ho, Sunny Chir and Horace Tan
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