Butterfly of the Month - February 2018

Butterfly of the Month - February 2018
The Green Baron (Euthalia adonia pinwilli)


A male Green Baron feeding on the ripened fruit of the Singapore Rhododendron

We cross into the Chinese Zodiac sign of the Year of the (Earth) Dog as Chinese communities all around the world celebrate the Lunar New Year on 16 February. The dog is the 11th animal out of the 12 selected animals that made it to the Jade Emperor's Great Race. The most defining characteristic of someone born in the year of the dog is their loyalty. They will never abandon their friends, family or work. Honest and just, they are popular in social circles. They are also good at helping others find and fix their bad habits.




Some geomancers predict that 2018 is going to be a tumultuous year for global events. A few predictions even pointed to some serious natural disasters in parts of the world. Then again, soothsayer predictions have always been here to stay, and to each his own whether to believe and take action to avoid 'bad luck' or to just ignore any form of fortune-telling, and live life to the fullest.




In the US, another senseless shooting took the lives of 17 innocent people at the Stoneman Douglas High School in Florida. The shooter, a former student who had been expelled for bad behaviour carried an AR-15 semiautomatic rifle with multiple magazines and was probably intent on taking lives when he went on his shooting spree that morning. As long as the US lawmakers remain adamant about "doing the right thing" as far as guns are concerned, such incidents will happen over and over again.



Over here in Singapore, we can only be thankful that the government has made the possession of firearms illegal and that such shooting incidents are highly unlikely to be caused by a civilian who has relatively easy access to assault rifles. It is hoped that governments of countries with strict gun control laws will continue to impose such laws so that what happened (and will continue to happen in the US), can be avoided in our respective homelands.



As the Chinese New Year celebrations continue for the next 15 days, Singaporeans wait with bated breaths for the announcement of the 2018 Budget. Rumours are rife that taxes, particularly the goods and services tax, will be raised. This usually translates into a higher cost of living as the GST affects practically every aspect of our daily life. Coincidentally, someone once said 'nothing is certain but death and taxes'.


A female Green Baron feeding on the flowers of the Javanese Ixora

Whilst looking for a species that features some auspicious red colour befitting of the Chinese New Year season, I selected one with some attractive red accents in its wings. Hence we feature the Green Baron (Euthalia adonia pinwilli) as February 2018's Butterfly of the Month. The attractive red spots, particularly on the underside of the wings of the male, gives the Green Baron a distinctive look.


A newly-eclosed male Green Baron clinging onto its pupal case

The Green Baron is a medium sized butterfly with an average wingspan of 55-65 mm. It is moderately common and regularly observed in urban parks and gardens, although it frequents the forested nature reserves as well. The main reason why the Green Baron is widely distributed, is because it caterpillar host plant, the parasitic plant, Malayan Mistletoe (Dendrophthoe pentandra),  can be found growing quite commonly on many other plants in urban parks and gardens.

The butterfly has a robust body like other species of the Euthalia genus (or collectively known by their common English name of "Barons").  Both the male and female of this species are strong flyers and skittish. They will fly rapidly away from any intrusion into their territory and head high up to the treetops, out of reach of any predators.

Male Green Barons feeding on Singapore Rhododendron fruit and Javanese Ixora flower

The male Green Baron is dark green on the upperside with a lighter green tornal area of the hindwing. The forewing has prominent white subapical spots and post-discal spots. The underside features the same subapical and post-discal spots but has a number of crimson spots at the cell area of the forewing and across the hindwing.

Female Green Barons feeding on Singapore Rhododendron fruit and Javanese Ixora flower

The female Green Baron has a broad white band across both wings with the veins blackened prominently. The tornal area of the hindwing on the upperside is an iridescent green with large black marginal spots and crimson spots on the tornal and apical area. The underside features large red cell spots on the forewing but fewer spots compared to the male.

Both the male and female are regularly observed to feed on rotting fruits. They like the ripened fruits of the Singapore Rhododendron (Melastoma malabathricum), although they have been seen on other types of flowering plants like Ixora and Lantana. They are extremely skittish if they are not feeding and difficult to approach without scaring them off.

The Green Baron has been successfully bred on the parasitic plant, Malayan Mistletoe (Dendrophthoe pentandra), a host plant that it shares with the Painted Jezebel, Peacock Royal and Great Imperial.

We would like to take this opportunity to wish all our Chinese readers a Happy and Prosperous Lunar New Year!

GONG XI FA CAI!!!

Text by Khew SK : Photos by Foo JL, Federick Ho, Huang CJ, Khew SK, Koh CH, Nelson Ong, Tan BJ and Horace Tan.

Random Gallery - The Green Baron

Random Butterfly Gallery
The Green Baron (Euthalia adonia pinwilli)

This week's random butterfly is the Green Baron (Euthalia adonia pinwilli).  This male was photographed feeding on the ripening fruit of Melastoma sp. by ButterflyCircle member, Koh CH.  The Green Baron is not rare, and is widely distributed across the island.  It is often observed in urban parks and gardens in locations where its caterpillar host plant, the parasitic Dendrophthoe pentandra is found.  Both males and females are attracted to fermenting fruits.

Mistletoes and Butterflies

Mistletoes and Butterflies
Ecological importance of Parasitic Plants

A female Banded Royal opens its wings to sunbathe. A recent addition to the number of butterfly species whose caterpillars feed on mistletoe

A parasitic plant is a plant that derives some or all of its nutritional requirement from another living plant. All parasitic plants have modified roots, called haustoria, which penetrate the host plant, connecting them to the conductive system – either the xylem, the phloem, or both. This provides them with the ability to extract water and nutrients from the host. Parasitic plants which derive water/nutrients from the hosts and are photosynthetic are known as "hemiparasites".


The large leaves of the Malayan Mistletoe are able to support the big numbers of the common urban species like the Painted Jezebel.

There are currently 10 known species of parasitic plants extant in Singapore. Quite a few of these species, commonly referred to as "mistletoes", can be seen attached to a variety of host plants - from shrubs to large trees all around Singapore. Mistletoes are believed to have medicinal properties and used in traditional medicine to cure a variety of ailments like cough, diabetes, hypertension, cancer and as a diuretic.


In the popular Asterix and Obelix comics, the druid Getafix adds mistletoe as a key ingredient in his magic potion 

In the popular comic series Asterix and Obelix, the mistletoe is a key ingredient in the magic potion that endows our two heroes with superhuman strength. The druid Getafix, who makes the concoction, is often depicted in the comics cutting mistletoe, hidden amongst the lush treetops with a golden sickle that preserves the magical properties of the mistletoe.


The hemiparasitic Chinese Mistletoe attached to the host

Parasitic plants are not the most welcomed plants amongst arborists, tree maintenance personnel and gardeners. This is because, by virtue of the parasitic nature of these plants, they anchor themselves to a host shrub or tree and extract nutrients from the host. In very severe infestations, the parasitic plants may stunt the growth of the host or even kill it. However, in most cases, a host can support these parasitic plants for decades without significant adverse effect on the host. Nevertheless, these under-appreciated and misunderstood parasitic plants are often pruned and removed from the host.


The shiny leaves of the Rusty Mistletoe are reddish brown when young, but turn a deep green when mature

What then, are the ecological functions of these "parasites" of other plants? Plants research has shown that mistletoes are keystone species in forests and woodlands. A keystone species is one which has a very significant influence in an ecosystem, and if removed may cause undesirable impact to the ecology. Many birds, insects and aboreal mammals build their nests among mistletoes. A wide variety of animals and insects feed on the leaves, shoots, fruits, flowers and nectar of mistletoes.


The Singapore Mistletoe Story by Francis Lim - a book about the parasitic plants in Singapore

Amongst the species of mistletoes in Singapore, three are of particular importance to butterflies. They are host plants to a variety of common to very rare species of butterflies. This article explores these species of mistletoes which are hosts to the caterpillars of these butterflies. It is also likely that the remaining 7 species of mistletoes may be caterpillar host plants for other species of butterflies, but this has yet to be discovered and hopefully recorded in time to come.

1. Malayan Mistletoe (Dendrophthoe pentandra)


The lush green leaves of the Malayan Mistletoe with flowers on its stem

The Malayan Mistletoe is by far the most common mistletoe in Singapore. It is a familiar site on roadside trees and in urban gardens, especially where plants are neglected or unkempt. It is quite often seen on plants like the Shui Mei (Wrightia religiosa) in private gardens, as well as any urban trees where birds spread the seeds of this parasitic plant, ranging from fruit trees like mango and chiku, to a wide variety of other roadside trees.







This common parasitic plant is a caterpillar host plant to at least five different species of butterflies across three families. These are :

1. Painted Jezebel (Delias hyparete metarete)
2. Green Baron (Euthalia adonia pinwilli)
3. (Tajuria dominus dominus)
4. Peacock Royal (Tajuria cippus maxentius)
5. Great Imperial (Jacoona anasuja anasuja)

The distasteful Painted Jezebel's caterpillars have somehow managed to sequester the chemicals from the Malayan Mistletoe to make itself unattractive to predators

Amongst these species, it is interesting to note that the aposematic Painted Jezebel is believed to be distasteful to birds and has somehow managed to sequester the chemicals in the Malayan Mistletoe as a protection against predators. This is something that the other 3 species that feed on the same host plant are not able to do so, or at least the adult butterflies are not known to be distasteful to predators.


The flowers of the Malayan Mistletoe

The Malayan Mistletoe is most likely dispersed mainly by the birds that feed on its fruits, and then transporting the seeds to other trees where the bird droppings, which contain the seeds, are deposited on the branches of other plants. As the seeds ripen, it will extend its haustoria (specialised roots) and penetrate into the host as it takes grip and grows. The haustoria of the Malayan Mistletoe tends to grow into a ball-like form as the plant matures.

2. Chinese Mistletoe (Macrosolen cochinchinensis)


A healthy growth of the Chinese Mistletoe

The next most common species of our local parasitic plants, is the Chinese Mistletoe, which, like the previous mistletoe, is also a stem hemiparasite. It attaches itself to the branches of its host and grows into a large bush that can span 1m-2m across. Depending on the size of the host, the growth of the Chinese Mistletoe can sometimes overwhelm and smother the entire host.










The Chinese Mistletoe is a caterpillar host plant to an even wider variety of butterfly species (some of which also feeds on the Malayan Mistletoe). These are :

1. Green Baron (Euthalia adonia pinwilli)
2. Centaur Oakblue (Arhopala centaurus nakula)
3. Peacock Royal (Tajuria cippus maxentius)
4. Banded Royal (Rachana jalindra burbona)
5. Felder's Royal (Tajuria mantra mantra)
6. Green Imperial (Manto hypoleuca terana)
7. Great Imperial (Jacoona anasuja anasuja)
8. Semanga superba deliciosa.

The flowers and fruits of the Chinese Mistletoe, on which the caterpillars of the Green Imperial and Banded Royal feed

The leaves of the Chinese Mistletoe are pinkish to red when young, turning light green and finally dark green as they mature. The mature leaves are stiff and slightly waxy. It should be noted, however, that several of the butterfly species' caterpillars actually feed on the flower buds and fruits of the Chinese Mistletoe, rather than the leaves.


A young shoot of the Chinese Mistletoe attached to its host via its specialised roots called haustoria

Like the Malayan Mistletoe, the Chinese Mistletoe is also mainly propagated by birds. Birds feed on the ripened globular fruits of the Chinese Mistletoe and once digested, the bird droppings are deposited on other plants as the bird moves in search for food. This gives a chance for the seeds to germinate and grow if a suitable host is found.

3. Rusty Mistletoe (Scurrula ferruginea)


The Rusty Mistletoe has a layer of fine brown hairs on the undersides of its leaves - giving it a "rusty" look

The last and slightly rarer species of mistletoe that plays host to butterfly caterpillars, is the Rusty Mistletoe. The leaves of this parasitic plant are green on top, but covered with a layer of fine brown hairs on the underside of the leaves, giving it a "rusty" appearance. As it grows, the main stem of the Rusty Mistletoe attaches to the host rather seamlessly, with a few side roots extending along the sides of the branch, growing the many little haustoria into the host.



The White Royal's caterpillars feed on the young shoots and leaves of the Rusty Mistletoe

This species of mistletoe is the caterpillar host plant for at least two species of Lycaenidae. These are:

1. Great Imperial (Jacoona anasuja anasuja)
2. White Royal (Pratapa deva relata) 

Both are rare species in Singapore. The White Royal was only recently re-discovered in 2007 but subsequently successfully bred on the Rusty Mistletoe.  The Great Imperial, which has been bred on all three mistletoes mentioned in this article, is the most versatile and its caterpillar accepts all three host plants.


A female White Royal perched on a leaf of the Rusty Mistletoe after ovipositing on the young shoots of the plant

Where it grows, the Rusty Mistletoe is not difficult to spot, as the brownish red appearance of its foliage sets it apart from its host. It grows into a relatively large bush that can measure 1-2m across. The flower of the Rusty Mistletoe has an interesting appearance of a brownish coloured hairy paw, whilst the fruit is a small hairy pseudo berry of about 1cm long.



Again, like the other mistletoes mentioned here, the Rusty Mistletoe is probably dispersed by birds that eat the fruits and then propagated by the bird droppings as the birds forage for food around the area. The seeds are also likely to stick onto branches of the host and then the haustoria anchoring the the plant to the host after the seed germinates, typical of the like the other species of stem hemiparasites.



In closing, we have taken a look at the more common mistletoes found in Singapore, and it is through keen observations with a dose of luck that we have discovered the range of species of butterflies that are dependent on these specific mistletoes for survival. If there is overzealous management of these "parasites" and their removal from their hosts, then it will critically threaten the existence of these species of butterflies (many of them rare) in Singapore. So the next time you see these parasitic plants around, leave them alone. The butterflies will thank you for that!

Text by Khew SK : Photos by Huang CJ, Khew SK, LohMY, Jonathan Soong and Horace Tan

References and Further Reading :

• A Guide to the Common Epiphytes and Mistletoes of Singapore 
• The Singapore Mistletoe Story: An Expose of a Botanical Marvel
• Mistletoes of Singapore