Life History of Green Baron v2.0

Life History of the Green Baron (Euthalia adonia pinwilli)

Butterfly Biodata:
Genus: Euthalia Hübner, 1819
Species: adonia Cramer, 1779
Subspecies: pinwilli Pendlebury & Corbet, 1938
Wingspan of Adult Butterfly: 50-60mm
Local Caterpillar Host Plants: Dendropthoe pentandra (Loranthaceae, common name: Malayan Mistletoe), Macrosolen cochinchinensis (Loranthaceae, common name: Chinese Mistletoe).

A male Green Baron.

Another male Green Baron in the company of a smalll ant.

Physical Description of Adult Butterfly:

On the upperside, the male is dark green with a lighter green tornal area in the hindwing. The forewings have white sub-apical and post-discal spots. Distinct red spots can be found in the apical area in the hindwing. The female has a broad white band, with blackened veins, across both wings. The marginal area of its hindwing is prominently marked in green.

A female Green Baron, showing its underside.

A female Green Baron, showing its upperside..

Field Observations of Butterfly Behaviour:

The Green Baron is moderately common in Singapore. They can be found in urban parks and gardens as well as in the nature reserves. The adults are strong and fast flyers and react readily to any intrusion into their territory. Both sexes have the habit of visiting flowers and ripened fruits.

A female Green Baron pudding on wet ground.

A male Green Baron visiting ripened fruits of the Singapore Rhododendron.

Early Stages:

A common parasitic plant, Dendropthoe pentandra, has previously been recorded as Green Baron's host plant. Recently, another parasite plant, Macrosolen cochinchinensis, was found to play the same role. Caterpillars of the Green Baron feed on mature leaves of the host plants, and rest on the leaf upperside between feeds.

Local host plant #1: Dendropthoe pentandra (common name: Malayan Mistletoe).

Local host plant #2: Macrosolen cochinchinensis (common name: Chinese Mistletoe).

The eggs are laid singly on a mature leaf (typically on the upperside) of the host plant. Each pale-brown egg has a low dome-shape with a base diameter of about 1.8-1.9mm. The surface is covered with large hexagonal depressions with yellowish hair-like protuberances emerging from adjoining corners. Each protuberance has a droplet-like terminal end.

An egg of the Green Baron laid on a leaf of the Chinese Mistletoe.

Two views of an egg of the Green Baron.

Two views of a mature egg of the Green Baron.

After about 4-5 days, the 1st instar caterpillar emerges and proceeds to eat the eggshell as its first meal. The caterpillar is yellowish in body colour and has a black head capsule. Its body sports ten pairs of long, yellowish and "fleshy" dorso-lateral protuberances. Black setae emanate from the body below these long protuberances and from a series of short dorsal protuberances. The caterpillar grows from an initial length of about 3.4mm to 6mm in about 2-2.5 days.

A newly hatched caterpillar, resting after devouring part of its egg shell, length: 3.4mm.

Two views of a early 1st instar caterpillar.

Two views of a late 1st instar caterpillar, length: 5.9mm.

The body of the 2nd instar caterpillar is predominantly yellowish green. All ten pairs of short protuberances seen in the 1st instar have lengthened considerably. Each is projected horizontally with numerous branched spines and is almost always pressed to the leaf surface. The protuberance is mainly pale yellowish in color. Some branched spines are black in colour. On the dorsum, pale brown patches appear between all ten pairs of protuberances. As growth progresses in this instar, these patches become darker brown, most prominently in the two patches between the 4th and 5th pairs. The 2nd instar lasts for 2.5-3 days with the body length reaching about 10-11mm before the moult to the 3rd instar.

A 2nd instar caterpillar, newly moulted, length: 6.5mm.

Two views of a 2nd instar caterpillar, length: 8.8mm.

A late 2nd instar caterpillar, dormant prior to its moult, length: 10.2mm.

The 3rd instar caterpillar is yellowish green in body color. The protuberances have all become much longer in proportion. The branched spines appear almost like a bird's feather, with the secondary spines arranged neatly around the main spine. The branched spines are black at the terminal end as well as at the one-third length from the end. Brownish dorsal spots appear on the dorsum, one between each pair of protuberances (except for the 3rd and 6th pairs). The 3rd instar lasts for about 3 days and reaches a length of about 16-18mm before the next moult.

A newly moulted 3rd instar caterpillar, length: 10mm.

Two views of a 3rd instar caterpillar, length: 16mm.

A late 3rd instar caterpillar, dormant prior to its moult, length: 17.5mm.

A 3rd instar caterpillar found in the field on a leaf of the Chinese Mistletoe.

The 4th instar caterpillar has similar appearance as in the 3rd instar. Spines on each long greenish protuberance are now mostly green and the two black portions near the terminal end of each portuberance more extensive. Each brown dorsal spot, except for the spots between the first two pairs of protuberances, now features a small white spot along the leading edge. After about 5-6 days in this instar, and its body length reaching 27-28mm, the caterpillar moults to the 5th instar.

A newly moulted 4th instar caterpillar, length: 16mm.

Two views of a 4th instar caterpillar, length: 22.5mm.

Two views of a late 4th instar caterpillar, dormant prior to its moult, length: 27mm.

The 5th instar caterpillar adopt a few changes in its appearance. Lateral spines in the previously black portions and terminal end of each portuberance have changed colour to pink, and the part between these two are now whitish in colour. Another observable change is in the brown dorsal spots which are now broader and more prominent in this final instar.

A newly moulted 5th instar caterpillar, length: 29mmmm.

Two views of a 5th instar caterpillar, length: 36mm.

A 5th instar caterpillar feeding on a leaf of the Chinese Mistletoe, length: 39mm.

This final instar lasts about 6-7 days with the caterpillar reaching a length of about 41-43mm. On the last day, the caterpillar ceases its feeding activity and its body shrinks in length. It then seeks out a spot on the underside of a leaf and stays put. There it spins large quantity of silk threads to make a silk mound, to which its posterior claspers are then attached to. Now the pre-pupa hangs from this anchor point in a head-down posture. A short transverse pale yellowish band appears on the dorsum about mid-body.

Two views of a pre-pupa of the Green Baron, early in this stage.

After about 1 day of the pre-pupal stage, pupation takes place. The yellowish green pupa is suspended with its cremaster firmly attached to the silk mound. It has a smooth body which tapers steeply towards each end from a yellowish transverse dorsal ridge (which ends at the wing case with a brown spot). A short series of brown spots appear along the edge of wing case, with the middle one the largest one and featuring an embedded beige spot. Length of pupae: 19-21mm.

The pupation event of a Green Baron butterfly.

Two views of a pupa of the Green Baron.

Ten days later, the pupa becomes considerably darkened, especially in the wing case area, signaling the end of the development of the adult still encased within. The next day, the adult butterfly emerges.

Three views of a mature male pupa of the Green Baron.

A newly eclosed male Green Baron clinging on its empty pupal case.

A newly eclosed female Green Baron clinging on 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, 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 Koh Cher Hern, Frederick Ho, Sunny Chir and Horace Tan

Butterfly of the Month - October 2016

Butterfly of the Month - October 2016
The Plain Tiger (Danaus chrysippus chrysippus)

It's the eighth month of 2016 already! Celebrated across the world wherever there are Chinese communities, the Mid-Autumn Festival (Zhong Qiu Jie) falls on the 15th day of the eighth lunar month of the Chinese calendar (although this actually fell in Sep according to the Gregorian calendar). This coincides with the autumn equinox when the moon is at its roundest and brightest. It is a time for family and friends to gather with their colourful lanterns and to admire this beautiful sight and give thanks for harmony, happiness and the fullness of life.





It was also a time where offerings of mooncakes and pomelos are made to the moon. In modern times, however, mooncakes come in more creative (but fattening!) forms from durian and chocolate fillings to multi-coloured snowskin and quadruple preserved eggyolk varieties. There were even recent comparisons of how many calories one would consume in a mooncake, compared to Singapore's local gastronomic delights (of the 'sinful' types like char koay teow, chicken rice and roti prata). No matter, this once-in-a-year indulgence is probably worth it!



The previous month also saw an unprecedented weather phenomenon in the most powerful typhoon recorded in 2016, called Meranti. With estimated wind speeds of up to 285 km/h, the super-typhoon struck the Philippines, Taiwan and China, causing widespread damage and fatalities. Hot on the heels of Meranti, another typhoon, Megi, albeit less powerful, made landfall in Taiwan, smashing into the island and causing at least four deaths and numerous injuries.




In Singapore, we saw the ninth edition of the Formula 1 Singapore Grand Prix. Reputed to be the only night F1 race in the world, the 2016 Singapore GP saw German Nico Rosberg on the winner's podium. One wonders if the interest in F1 waning in Singapore, as it was reported that ticket sales for 2016 was possibly the lowest ever, since the F1 came to Singapore in 2007. Nature buffs were treated to a sight where a Water Monitor ran across the F1 track and caused some ruckus amongst the race officials.



Back to nature, and we feature October's Butterfly of the Month 2016, the Plain Tiger (Danaus chrysippus chrysippus).  This common but pretty butterfly has become a dominant species in our urban butterfly gardens where its caterpillar host plants, the Blood Flower (Asclepias currasavica) and the Crown Flower (Calotropis gigantea) are cultivated. At times, it can almost be considered abundant, as many Plain Tigers flutter freely amongst the nectaring plants.




Back in the mid-90's when I was participating in butterfly biodiversity surveys with the National Parks Board, the Plain Tiger was not as common as it is today. One might even consider the species a relatively rare species, as few individuals were sighted. Today, with the widespread cultivation of its caterpillar host plants in urban gardens, the Plain Tiger is now a regular feature species in many of these butterfly gardens.




The Plain Tiger has rich fulvous orange forewings with a broad black apical border bearing a series of white spots. Two forms occur in Singapore - form-chrysippus, where hindwings are unicolourous with the orange forewings; and form-alcippoides, which has white hindwings. The white-hindwinged form is by far the commoner of the two forms in Singapore.






Whilst it is considered common, the Plain Tiger tends to be quite local in that it is always found not far from where its caterpillar host plants are cultivated. It is seldom seen in the forested nature reserves and is more of an urban butterfly species.




Like many other species of the Danainae sub-family, the Plain Tiger displays aposematic colouration which advertises its impalatability to would-be predators. It serves as a model to the female of the Danaid Eggfly (Hypolimnas missippus missippus). The latter species has been found in Singapore, but extremely rare. However, thus far, there is no sighting of the female of the Danaid Eggfly in Singapore.



The Plain Tiger flies with a slow and unhurried flight, fluttering from flower to flower and frolicking amongst other individuals of the same species. It is partial to the semi-dried plant of the Indian Heliotrope (Heliotropium indicum). The male Plain Tiger is also attracted to the Rattlebox Pea (Crotalaria retusa), where it claws the pea pod and then feeds on the fluids that the damaged pea pod exudes.





The male Plain Tiger can be distinguished from the female by an extra 'sex brand' on the hindwing. The white spot which is surrounded by black ring, is quite distinct and obvious and easily tells apart the males from the females. This spot, which bulges slightly, consists of a cluster of specialised scent scales used to attract females.




The colourful caterpillar feeds quite openly and can defoliate the host plant quite quickly. As the caterpillars sequester the poisonous sap from the host plant, they are distasteful to predators and birds tend to leave them alone.

Text by Khew SK : Photos by Bob Cheong, Sunny Chir, Chng CK, Brian Goh, Khew SK, Loke PF, Bobby Mun, Anthony Wong, Mark Wong and Benjamin Yam

Eye In the Sky

Eye In the Sky
Butterfly Gardens : A View from the Top


An aerial view of the Butterfly Garden at Fusionopolis North

Singapore's urban butterfly gardens have been featured on this blog regularly. Our winged jewels thrive in these specially-planted gardens that attract them to visit the flowering plants to feed and their host plants to lay their eggs. With judicious planting of appropriate butterfly nectaring and host plants, these butterfly gardens can attract many species of butterflies.

I have always wondered what these urban gardens would look like from the viewpoint of a butterfly, soaring high in the sky and scanning the landscape below for their favourite flowers. Imagine a Common Birdwing (Troides helena cerberus), flying majestically 20-30 metres or even higher, above the lush greenery, and looking down and searching for its host plants or some of its favourite nectaring plants when it is hungry.

Human eye view of the Butterfly Garden at Fusionopolis North

Thus far, we have been featuring photographs of our butterfly gardens from a human's perspective - walking on the ground and looking around at the butterflies fluttering from flower to flower. Our photos of the butterflies feeding, sunbathing or frolicking around is limited to what we can encounter at our eye-level. Our views of the greenery that surrounds us, is what we can see, with our feet planted firmly on the ground.

Recently, a colleague loaned me his quad-copter drone and I thought that it would be a good opportunity for me to visit some of the butterfly gardens that I had featured before, and how they would look like from the air. These days, there are so many types of flying drones available online and in technology shops locally and abroad. As can be expected, quite a large percentage of these drones are made in China - even the "high end" DJI Phantoms that are very popular amongst drone enthusiasts.

The Blade Chroma quadcopter drone with CGO3 4K camera

So I got my hands on a Yuneec Blade Chroma that comes with a CGO3 4K camera that can shoot 30fps videos or 12 Mp stills. The integrated 3-axis gimbal holds the camera still and video footages appear very stable. After logging a few hours' flight time as a novice drone pilot, I set out to some of our local butterfly gardens to take a look at how they look like "from up there".

Butterfly Sanctuary @ the Meadows, Gardens by the Bay

Butterfly Sanctuary @ the Meadows, Gardens by the Bay

The first butterfly garden was the Butterfly Sanctuary at the Meadows, Gardens by the Bay. Taking the drone up to a cruising height of about 50m, the landscaping at the Butterfly Sanctuary appeared rather thin and arranged along a linear path. The nectaring plants flanked the path, visible from the air, where most of the butterfly activity can be expected. The surrounding greenery and taller trees provided shade and expanded the area where the butterflies flew around.

Hort Park Butterfly Garden

The next butterfly garden that I visited was the one at Hort Park. Originally in an enclosure, the butterfly garden is now an open garden with free-flying butterflies like most of our environmentally-friendly butterfly gardens. The layout of the butterfly garden, complete with host and nectaring plants, is designed on the standard plot sizes at Hort Park, and strung in a linear fashion. Over the years, the tall trees along the trail have grown to a significant height, and provides shade for parts of the butterfly garden.

Butterfly Garden @ Hort Park

From the top, the clusters of host and nectaring plants like the Snakeweeds, Lantanas, Stringbush, Golden Dewdrops and Dutchman's Pipevine appear like a mass of green and the colours of the flowers were indistinguishable from 30-40m up.

Fusionopolis Butterfly Garden

Moving to the next urban garden nearby, I visited the Fusionopolis North Butterfly Garden. This recently-completed butterfly garden was still rather open and unshaded as the larger trees have yet to mature and extend their green canopies. From the air, the network of concrete footpaths was quite distinct as were some of the hardscape features.

Butterfly Garden at Fusionopolis North

Up at 35m above, this butterfly garden appears more squarish in plan, with all the butterfly-attracting plants visible in a patchwork of greenery with the sinuous footpaths winding through the garden. The large trees flanking the butterfly garden provided a boundary and much-needed shade from the hot environment where the newly-landscaped gardens were planted.

Jurong Eco-Gardens Butterfly Garden

Butterfly Garden at Jurong Eco Garden

The last butterfly garden that I visited with the Blade Chroma, was the one at Jurong Eco-Gardens. Located in a more sub-urban environment with slightly more undeveloped greenery (for the moment), the butterfly garden is also laid out along a linear trail, with the butterfly-attracting plants flanking the trail.

A closer butterfly-eye's view of the Butterfly Garden at Jurong Eco Garden

From the air at about 40m up, the large red clumps of the Pagoda Flower (Cleredendron paniculatum) were visible. The wide boardwalk can be clearly seen, and the surrounding waterbody and larger adjacent trees formed a lush boundary to the butterfly garden.

Take a flight around the butterfly garden at Fusionopolis North! (You may have to run the video a couple of times to get a better resolution)

And so you now know how these butterfly gardens look like from a high-flying butterfly's viewpoint. At this point in time, it is unlikely that a drone can successfully take close-up butterfly shots at the treetop canopies. But at the rate technology is advancing these days, someone may just invent a zoom lens that can do just that in the future!

Three Common Tree Nymphs (Idea stolli logani) soaring high in the air

Text and Photos by Khew SK & Loke PF

Special thanks to my colleague and good friend, Vincent, who loaned me his Blade Chroma quadcopter (and is in the process of 'poisoning' me to get the awesome DJI Phantom 4 drone)

For those who are curious, there are currently no permits required to purchase a drone in Singapore. However, there are regulations and limits on flying a drone and you should familiarise yourself with the prevailing regulations under the Civil Aviation Authority of Singapore (CAAS).