17 November 2019

Flight of the Imperials

Flight of the Imperials
Featuring Singapore's Imperial Butterflies

A Branded Imperial perches on a leaf in the shaded forest understorey

The English word "imperial" is usually used to refer to things or people that are or were connected with an empire or pertaining to an emperor or empress. When the early collectors coined the name Imperial for some species of the Lycaenidae family, it is highly likely that they were using the word to describe these majestic butterflies that awed them with their breath-taking colours and beauty.

A Green Imperial stops to rest on the flower of the Javanese Ixora

In the world of butterflies, the Imperials are pretty, colourful and usually long-tailed species belonging to the sub-family Theclinae of the Lycaenidae family. Singapore is home to five of these Imperials, all of which are forest-dependent and usually found only in the heavily forested nature reserves. Of the five, only one is considered common and regularly seen by nature enthusiasts.

A female Great Imperial feeding on the flower of the Javanese Ixora

This blogpost takes a look at these five Imperial butterflies found in Singapore. Interestingly, each one of the five belongs to a different genus. All have orange with white undersides and black tornal markings. Their long tails are remarkable features on these species, and two of them probably sport the longest tails amongst the extant butterflies in Singapore.

1. The Branded Imperial (Eooxylides tharis distanti)

A Branded Imperial shares the sweet sap of the Bandicoot Berry with some ants

The first of the Imperials is the Branded Imperial. This species is by far the commonest of the five species and is regularly found along forest paths in the shaded understorey of our nature reserves. At times, several individuals can be seen together, particularly when they are feeding on the young shoots of the Bandicoot Berry (Leea indica).

A male Branded Imperial opens its wings to sunbathe.  Note the prominent brands on its forewings

The wings are black above with blue-dusted tornal area on the hindwing. In the male, a prominent "brand" can be seen on the upperside of the forewing. This could be why the butterfly is named Branded Imperial. The underside is reddish-orange with the hindwing bearing black sub-marginal spots on the white tornal area. There are 3 tails on the hindwing, of which the one along vein 2 is the longest.

The species' caterpillar feeds on the invasive weed Smilax bracteata which it shares with another Lycaenid, the Yamfly. As this non-native weed is very widespread in the nature reserves (despite efforts to remove the weed), the Branded Imperial has become a common species in Singapore.

2. The Common Imperial (Cheritra freja friggia)

The Common Imperial is a moderately rare species but is quite widespread across the island. Although found in the forested nature reserves, it can sometimes be found in urban parks and forested ridges in Singapore. It is usually observed singly and prefers to stay at treetops. It has a habit of perching on favourite leaves and returns time and again to the same perches as it flies around.

A male Common Imperial sunbathing with its wings opened to show the purple-blue uppersides

The male Common Imperial has purple-blue forewings on the upperside, whilst the female is dark brown. There are large black spots on the tornal area of the hindwing. Te underside is mainly white, with part of the forewing and the apical area of the hindwing shaded a light orange. The tornal spots on the hindwing are overlaid with metallic blue-green scaling. It has 3 tails of which the one at vein 2 is the longest.

The species' caterpillars feed on two species of common roadside trees, the Wild Cinnamon and the Red Saga. It has also been bred on other forest plants that are mainly found in the nature reserves. The species is observed to sunbathe with open wings at certain hours of the day at sunlit spots.

3. The Green Imperial (Manto hypoleuca terana)

The Green Imperial is considered rare in Singapore. It is usually seen at the forest edges of the nature reserves, feeding on the nectar of flowering plants. It is a fast-flying species that probably prefers to stay at the treetops.

The male of the Green Imperial is a shining bluish-green above, with broad black apical area on the forewing. The underside is largely orange and unmarked on the forewing, whilst the hindwing has black sub-marginal spots and streaks. The female is dark blackish-brown above with the usual black spots on a white tornal area on the hindwing. The underside of the dorsal area of hindwing is white, whilst the other areas of the forewing and hindwing are orange. The species has 2 tails - a relatively long tail and vein 2 and a short stubby one at vein 3.

Female Green Imperial. Top : Underside Bottom : Upperside

The species is one of several rare Lycaenidae that feeds on the parasitic plant, Macrosolen cochinchinensis, that can be found growing on large trees and bushes all around the island. The females have been observed ovipositing on the leaves of the host plant in the early afternoon and lays her eggs on the young shoots of the plant.

4. The Great Imperial (Jacoona anasuja anasuja)

Another rare Imperial, the Great Imperial has been observed only in the forested nature reserves of Singapore. The adult butterfly appears to be another tree-top dweller but occasionally can be seen to descend to low level shrubbery to feed or oviposit. When disturbed, it can fly rapidly up the treetops.

Top : Female Great Imperial Bottom : Male Great Imperial

The male of the Great Imperial is a deep shining blue on the upperside with an oblique band running across the apical area of the forewing. The female is predominantly brown above with a white tornal area on the hindwing. The underside is mainly orange with the forewing apical area a darker shade. The dorsal area of the hindwing is white with the tornal black streaks and spots. Both sexes have tails, where the males have a shorter sword-like tail at vein 2 whilst the female's tail is much longer.

The caterpillar host plant of the Great Imperial is the common Malayan Mistletoe. However, the species is not usually found in urban parks and gardens. It is found along the forest fringes and where it is observed, it is perched on the uppersides of leaves with its wings folded upright. Both sexes also descend from the treetops to feed on flowering plants.

5. The Grand Imperial (Neocheritra amrita amrita)

The last of the Imperials is also a rare forest-dependent species that is quite local in distribution. Its caterpillar host plant is found in the nature reserves and is quite rare. The plant has yet to be positively identified. However, the Grand Imperial was seen in numbers on the military-training island of Pulau Tekong in the early 2000's during a period of biodiversity surveys. It is not known if they are currently still as common.

A male Grand Imperial feeding on flowers

The male Grand Imperial has a royal blue upperside, with the apical areas of both wings black bordered. The female is dark brown and largely unmarked, except at the white tornal area where there are black spots. The underside of the forewing and costal half of the hindwing is dark orange whilst the remaining part of the dorsal area of the hindwing is pure white.

A female Grand Imperial sunbathing

The Grand Imperial has the longest tails of any Lycaenidae found in Singapore. It has 3 tails, of which the longest tail is at vein 2, whilst there are two shorter tails at veins 1b and 3 of the hindwing. The male has a prominent raised 'disc' on the underside of the forewing.

Text by Khew SK : Photos by Huang CJ, Khew SK, Simon Sng, Jonathan Soong, Horace Tan and Tea Yi Kai

10 November 2019

Black and White

Black and White
Featuring some black and white butterflies

Butterflies are traditionally portrayed as pretty insects adorned in all colours of the spectrum, fluttering gracefully amongst flowers. Moths, on the other hand, are often depicted as drab ugly creatures that only fly at night. In nature, and amongst Lepidoptera, this may be furthest from the truth!

There are numerous colourful moths in our environment - some even more spectacularly coloured than butterflies. On the other hand, there are also many drab-coloured and relatively unattractive butterflies. The colour of a butterfly's wings are often the subject of attention and enthusiasts tend to assess a butterfly's "attractiveness" by the colour and pattern of its wings.

However, like all of Mother Nature's creations, there is always a great diversity in the appearance of our natural world. Butterflies are no exception. This blogpost takes a look at some species of butterflies whose wings do not feature any colour of the visible spectrum, but are predominantly black and white, both on the upperside and underside of their wings.

Almost all black and white, the Helens have red or blue ocelli adorning their hindwings

Amongst the Birdwings and Swallowtails in Singapore, there are some species that have primarily black wings with some white patches. However, many of these also feature red, blue and other coloured lunules/eyespots that would make them more 'colourful' than just appearing as black and white butterflies.

Amongst the Pieridae are some species that are mainly white in appearance, with their veins or wings featuring black borders and margins. Some of these species would qualify as black and white candidates in this article. The male Striped Albatross, the Cabbage White and the seasonal migrant, the Plain Puffin can all be considered black and white species in this family.

The Crows from the Danainae subfamily are predominantly black butterflies with white markings

The next group would be the Danainaes, of which the Crows in particular, feature a few species that are predominantly black, with some white spots and streaks on the wings. The Crows appear black as compared the Albatrosses in the preceding family that appear white. The noteworthy species are the Spotted Black Crow, Malayan Crow, King Crow, Blue Spotted Crow and Striped Black Crow that would qualify as black and white species.

The Tree Nymph species are large and slow flying black and white butterflies

Also amongst the Danainaes, are the Idea species or more popularly called the Tree Nymphs. These are large and spectacular black and white butterflies that are attractive in their own right, despite not have any other prominent colours on their wings, except for black and white.  The Common Tree Nymph and the Mangrove Tree Nymph are the black and white species that can be found in Singapore.

Only the uppersides of the Sailors and Sergeants are typically black and white.  Some of the species have orange, brown or bluish-grey undersides.

Some of the Sergeant and Sailor species of the subfamily Limetidinae are also black and white striped on their upperside of their wings. However, most of them have either orange, brown and bluish gray undersides which would make them black and white candidates only when viewed from their dorsal side.

The Chequered Lancer is one of the black and white species amongst the skippers but on the upperside, the wings have orange-brown spots

Most of the other species in the remaining subfamilies amongst the Nymphalidae, the Riodinidae and Hesperiidae are largely coloured and very few can be considered true black and white butterflies. Some of the skippers come close to be purely black and white, but either their upperside or underside are brownish or with coloured accents that do not make them true black and white butterflies.

The Polyommatinae species in the Lycaenidae family feature some true black and white butterflies

In the family Lycaenidae, three Singapore-extant species, the Elbowed Pierrot, Malayan and the Quaker can be considered black and white species as both their under and uppersides are predominantly of black and white or grayscale colouration in appearance.

With that short introduction to our black and white species found in Singapore, see if you can spot any more that may come over from neighbouring countries in future. These species are considered the "Zebras" of our butterfly world - just simple black and white like the mammalian namesake from the horse or Equidae family.

Text by Khew SK : Photos by Sunny Chir, Federick Ho, Khew SK, Koh CH, Loke PF, Jonathan Soong and Benjamin Yam

02 November 2019

Butterfly of the Month - November 2019

Butterfly of the Month - November 2019
The Sumatran Gem (Poritia sumatrae sumatrae)

A Sumatran Gem perches on a leaf in the shaded forest understorey with its wings folded upright

We are now into the 2nd last month of 2019 trundling towards the end of a very tumultuous year. It has been a rather difficult year for many of us, from personal challenges and misfortunes to tough business environments and tragic world events. The US-China trade war continues to trigger unprecedented impacts across many countries and individuals, creating direct and indirect uncertainties to people around the world.

Not too far away, the protests in Hong Kong that started in July seems to have continued unabated for the past 4-5 months. With each passing month, the protests appeared to have become more intense and violent, with properties and public amenities damaged or destroyed. The world watches with curiosity and shock. as there seems to be nothing any external party can do to help resolve Hong Kong's domestic issues except for it to be tackled from within. What exactly is the outcome or objective of the protests seem to elude logical understanding from our external perspective.

As suddenly it had started, the haze disappeared just as quickly and people in the region went back to their normal lives. Until the next burning season, that is. And then the finger-pointing and grousing starts all over again as people scramble for their N95 masks and avoid strenuous outdoor activities (like butterfly watching outings!)

At home, domestic issues that dominated the news include Personal Mobility Device (PMD) accidents and recalcitrant behaviour of a minority of such users who continue to flout the law. On another front, the issue between the self-entitled and lack of basic graciousness when dealing with condominium rules and the security personnel who enforce them, was heatedly debated on social media. The ugly side of online vigilantism also showed how social media frenzy tends to quickly breach the boundaries of extreme behaviour.

A pair of male Sumatran Gems perched on a leaf side by side

Almost all over Singapore, the number of butterflies seemed to be generally on the decline. Our usual "hunting grounds" tended to turn out much lower counts and sightings over the past couple of months compared to previous years. Perhaps the prolonged hot and dry spell, combined with the haze may have had some environmental effect that limited the number and diversity of butterfly species. Let us see if this changes in the coming cooler and wetter months and into the start of 2020.

The Butterfly of the Month for November 2019 is a "gem" of a butterfly - small but spectacularly coloured Sumatran Gem (Poritia sumatrae sumatrae). A species that usually frequents the heavily shaded forest understorey, the iridescent emerald green of the male tends to catch an observer's attention quickly as the butterfly opens and closes its wings when it stops to rest.

A mating pair of Sumatran Gems

Moderately rare and local in its distribution, the Sumatran Gem is one of two species from the genus Poritia that can be found in Singapore. At times, it is observed along forest edges in the early hours of the morning, flying and stopping to sunbathe with open wings. Most of the rest of the day, it is found in the forest understorey and flits around from perch to perch with its wings folded upright.

The beautiful emerald green upperside of a male Sumatran Gem

The male Sumatran Gem is a bright metallic emerald green, with thick black apical borders on its upperside. In the forested areas, males tend to fly around from leaf to leaf, stopping and then opening and closing its wings for a few moments before settling to rest with its wings closed upright. It rarely opens its wings fully, preferring a semi-opened position most of the time.

The Sumatran Gem is a sexually dimorphic species, with the purple female very different in appearance from the male

The female is a light purple above with reddish streaks and has black marginal markings on both wings. Females are much rarer than the males and are less often spotted. They too, prefer forest edges in the nature reserves and are more often encountered in the heavily shaded forest understorey.

The underside of the Sumatran Gem is reddish brown with thick striations. Much of the reddish striations on both wings are black-bordered. The hindwing is mildly scalloped with the cilia blackened. The legs of the butterfly are banded black and white, whilst the compound eyes are transparent. The antennae are orange tipped.

Text by Khew SK : Photos by Goh EC, Huang CJ, Khew SK, Loh MY, Jonathan Soong, Tee Wee Kiat, Anthony Wong and Mark Wong