22 April 2017

Featuring some recent additions to the Singapore Checklist

Butterflies of Singapore Checklist
Featuring some recent additions 

In our blog article on the the review of the year 2016, we referred to some seven new additions to the Singapore Checklist, bringing the total number of butterfly species observed in Singapore to 331. This weekend's article features four of these species and offers some insights on the status of these species in Singapore. Very often, we have migratory species that make their occasional appearance in Singapore and due to their seasonality, these are classified as 'seasonal migrants' in the Singapore Checklist.

However, there are still some lookalikes that are hard to distinguish, except perhaps with physical voucher specimens or even using DNA barcoding to establish a distinct species that occurs in our environment. Then there is always the possibility that some species have eluded observation by hiding deep in Singapore's forested nature reserves. They are probably rare, but resident species, yet to be discovered or re-discovered.

A dead Dark Jungle Glory (Thaumantis noureddin noureddin) found at NTU

Amongst one of the surprising finds last year, was the Dark Jungle Glory (Thaumantis noureddin noureddin). A relatively pristine individual was found by NIE lecturer Assistant Prof James Lambert on the premises of the Nanyang Technological University. The butterfly was found dead with its wings spread open.

The Dark Jungle Glory is described as being dark brown on the upperside with the wing bases a shining purple-blue, with a fascia of diffuse white spots on the forewing. The dark-greyish brown underside has a white post-discal line which is shaded with dark brown and a number of ocelli on the hindwing. The species is often found in bamboo thickets and fly close to the ground in dark heavily shaded habitats.

A Dark Jungle Glory in its typical habitat amongst dead leaf litter on the forest floor

It is curious that this species, considered a re-discovery is still found in Singapore after all these years. We do not believe that this is a seasonal migrant, as the Dark Jungle Glory stays in shaded habitats close to its likely caterpillar host plant of bamboos. It is probably rare, but has remained extant in Singapore in very limited habitats. It should be looked for in future, particularly in the NTU area which still has pockets of undisturbed heavily shaded forested areas.

The next large species that has been observed in Singapore over the past years, is the Dark Blue Tiger (Tirumala septentrionis septentrionis). This butterfly, which resembles the Glassy Tigers of the Danainae subfamily, has been observed from time to time, and it was not until a confirmed shot by Chung Cheong was recorded recently. It was probably missed due to its resemblance to the Glassy Tigers and proved elusive.

A Dark Blue Tiger shot in Singapore in 2006

The Danainae have been known to be strong flyers and display migratory tendencies. That the Dark Blue Tiger has been sighted several times in Singapore, is therefore not surprising, as the tough "Tiger" can survive rough conditions that would have been fatal to other more delicate species. The species is not uncommon in Malaysia, and is often seen in butterfly enclosures where it is one of the farmed species for display. The Dark Blue Tiger is a large butterfly with narrow elliptical bluish markings. It resembles other species in the Parantica and Ideopsis genus but it appears much bluer in flight.

A Ganda Dart with the hindwing patch with the veins not darkened

The next two species to be discussed are skippers from the Hesperiidae family. It is often challenging to identify skippers from field shots - particularly amongst the lookalike species, of which several species can be very similar in appearance. Amongst these are the species from the genus Potanthus and Telicota. These orange-black skippers are small, skittish and appear frustratingly identical to butterfly watchers.

The species referred to as the Ganda Dart (Potanthus ganda). This species is of the same size and appearance as the more commonly found Lesser Dart (Potanthus omaha). However, the Ganda Dart prefers the forested areas in the nature reserves in Singapore whilst the Lesser Dart is more widespread and can be found in urban parks and gardens.

The Ganda Dart differs from the Lesser Dart in that the veins on the yellow band on the hindwing above are not blackened. It is also described to have deeper orange colouring (but a rather unreliable characteristic when comparing weathered individuals with pristine ones). Both the Ganda Dart and Lesser Dart flies with the usual skittish skipper habits and often stop with their wings opened in the typical skipper fashion. Photos of the Ganda Dart appeared online as early as 2010 but was not validated until recently, with breeding records.

The next skipper of interest is the rare species from the genus Zographetus. These are forest-dependent butterflies and are rarely, if ever, found outside the sanctuary of the nature reserves in Singapore. Three species have been listed as extant in Singapore by the early authors. However, only one - Zographetus doxus (Spotted Flitter) has been recorded with certainty.

A Rusty Flitter perches in the shaded understorey in the nature reserves

Over the years, another closely related species, the Rusty Flitter (Zographetus ogygia) has been photographed but not included in the Singapore Checklist due to the uncertainty relating to their superficial features. However, as more and more evidence appeared, the confidence level of distinguishing these two species has risen and therefore the 2nd species Zographetus ogygia has been added to the Singapore Checklist. A 3rd species, Zographetus rama, recorded previously in Singapore, should be looked for.

It is highly likely that there continues to be discoveries or re-discoveries in our Singapore's forests where rare species have eluded observation till now. Many of these species may be cryptic in appearance, with several species looking very similar to each other. The skippers, in particular, the brown ones, tend to be difficult to identify from a single field shot and specimens may need to be collected to establish the ID of the species with greater certainty.

Text by Khew SK : Photos by Chung Cheong, Khew SK, Koh Cher Hern, James Lambert, Bobby Mun, Kurt Orion, Nelson Ong, Jonathan Soong, Tai LA and Horace Tan

Note : The English Common Name of Zographetus ogygia follows the Butterflies of Thailand 2nd Edition by Pisuth Ek-Amnuay. Elsewhere it is known by other common names but we will accept the Southeast Asian name as "Rusty Flitter".

15 April 2017

Butterfly of the Month - April 2017

Butterfly of the Month - April 2017
The Silver Forget-Me-Not (Catochrysops panormus exiguus)

A quarter of 2017 had come and gone. The fourth month of the year seems quiet enough, although the uncomfortable tension that came with two US military strikes on Syria and Afghanistan lingers in the air. It would appear that the Trump administration will not hesitate to show its destructive force in the use of (currently) conventional weapons in sending a strong message to ISIS.

Already, the amassing of US military hardware in South Korea, and the reciprocal response from China is causing consternation in north-east Asia. Will the US, which appears to be emboldened by their military strikes on the ISIS strongholds, also use force to teach North Korea a lesson? Will North Korea stay quiet in the face of US hostilities, as Syria and Afghanistan appear to be? We live in times of great uncertainty indeed.

I was in China waiting for my flight to take off, when news of the US strike on Afghanistan broke. Although far away, the impact of the incident caused quite a bit of delays at airports in China. Despite no one mentioning that the 'temporary closure' of certain airports in China and the flight delays that ensued were a result of the international incident, we can only speculate that China was on high alert during that short period of time.

And then there was the United Airlines incident that buzzed the internet for a few days. Due to the prevailing policy that airlines in the US are allowed to over-sell their flights, whenever a flight is full, the airline will invite passengers to forego their seats (for a little compensation) to accommodate the airline's policy. However, the incident on United Express Flight 3411 where a "booked, paid and seated" passenger was selected at random and physically dragged out of the plane by security personnel.

I recall that some years ago, I was offered to take a later flight when the plane that I was booked on, was full. The American Eagle counter staff was polite and persuasive and I agreed to take a US$150 compensation and took a flight that was 3 hours later. The difference was that I was persuaded not to take the flight before I boarded the plane. The current incident where a passenger was violently dragged off the plane after being seated is totally unacceptable, which is probably why it set off an internet storm all around the world.

Perhaps living the life of a butterfly is a lot less complicated? This month, we feature a small hairstreak or Lycaenidae species called the Silver Forget-Me-Not (Catopyrops panormus exiguus). It was re-discovered in Singapore back in 1997. References indicated that this species was not seen in Singapore since the late 19th century and was therefore considered 'extinct'. However, a small population was observed in the Khatib Bongsu area and Pulau Ubin. Subsequent sightings of this species on Sentosa and various parts of the island indicated that the species is extant and resident in Singapore.

Considered a moderately rare species, the Silver Forget-Me-Not is usually encountered singly where it flies with a rapid erratic flight amongst the low shrubbery. The caterpillar host plant is Pueraria phaseoloides which is a "weed" growing in open wastelands and cleared areas.

Comparison between the Silver Forget-Me-Not and the Forget-Me-Not showing the position of the costal spot on the forewing edge on the underside of the forewing.

This species is not to be confused with its lookalike cousin, the Forget-Me-Not (Catopyrops strabo strabo). Almost identical in most respects, these two species are hard to separate in the field, as they frequent the same habitats and display the same habits. The key distinguishing difference is the location costal spot on the underside of the forewing.

Upperside of the male and female Silver Forget-Me-Not

The Silver Forget-Me-Not is pale shining blue on the upperside of the male. The female is heavily black dusted with broad black apical area on the forewing, and dull blue wing bases. The underside is greyish white with the usual Lycaenidae streaks and spots. The hindwing has a long filamentous white-tipped tail at vein 2.

Puddling Silver Forget-Me-Nots

At certain times of the day, both males and females of the Silver Forget-Me-Not can be observed to open their wings partially to sunbathe. These are the only times when one can observe the uppersides of the wings, as they normally stop with their wings folded shut, even when they feed on flowers or when they puddle on damp footpaths and streambanks.

Text by Khew SK : Photos by Sunny Chir, Federick Ho, Khew SK, Koh CH, Loke PF, Nelson Ong, Jonathan Soong, Lemon Tea and Mark Wong

08 April 2017

IPSG Talk @ Deyi Secondary School

IPSG Talk at Deyi Secondary School
Introduction to Butterflies

A group of teachers from the IPSG session at the Deyi Secondary School butterfly garden

Last week, I was invited to give a talk about butterflies to a group of teachers at Deyi Secondary School. The Principal of the school, Mrs Lim AP, had recently set up a butterfly garden in her school grounds and thought that a sharing session amongst her teachers would be useful. Coincidentally, she had a Science Instructional Programme Support Group (IPSG) of Cluster N6 that day, so we had another group of teachers from schools within the cluster who joined the talk.

Many of the teachers had biology background and hence it was easier to use basic taxonomic terms about butterflies without having to elaborate on the technicalities of the terms. My talk was calibrated more for the layman, and covered basic topics like butterfly morphology, behaviour, ecology and conservation.

Teaching the teachers about butterflies at the sharing session

It is always interesting to observe how people are surprised to learn of the rich butterfly diversity on our little red dot. Taking into account the seasonal migrants, we have recorded 331 species in Singapore at the end of 2016. Obviously, discoveries and re-discoveries will continue - both at the technical level and also at the field observation level. There will always be surprising finds every year, and we hope that even within the 714 sq km of our little island, lurks species that have been hidden from us all these years.

Given the teacher-centric audience, I also launched my typical quiz on the identification between butterflies and moths. As with previous audiences, it was always fun to see how people have preconceived ideas of what they consider are moths, and what butterflies should look like. In so far as I've surveyed, most beginners would not get a clear "pass" on the quiz. Although biologically, both butterflies and moths fall under Lepidoptera, the layman has always been curious about the differences between a butterfly and a moth.

In the one hour talk, the audience was kept alert and intrigued about butterflies and I was glad to see that most were quite interested at the information provided. I suppose having lots of pretty pictures of butterflies helped in what could have been a 'boring' subject to some.

Some hands on experience with caterpillars.  Tian reassuring the teachers that butterfly caterpillars are quite harmless

I was assisted by my two friends Tian HM and Or CK. Tian was the man behind the landscaping of the butterfly garden at Deyi Secondary School and he conceptualised the planting beds and the species of host and nectaring plants to attract butterflies to the garden. CK helped with recording the talk and her bubbly personality is always welcome at any gathering.

After the talk, we brought the group out to the butterfly garden facing Ang Mo Kio Street 42. It was a quiet corner of the school, slightly away from the buildings and partially shaded by some trees. Despite its proximity to the road, the site was slightly elevated and hence provided a relatively conducive area for butterflies to roam about.

Visiting the butterfly garden

Tian did a good job of mixing host plants, nectaring plants and other filler plants in the small area of about 250m2 that formed the butterfly garden. Even at the late hour of almost 5pm in the evening, we spotted species like the Common Grass Yellow, Chestnut Bob, Striped Albatross and Chocolate Pansy fluttering around. We also saw caterpillars of the Leopard Lacewing, Tawny Coster and Plain Tiger on the host plants.

Caterpillars in the butterfly garden, and educational signage on the plants that have been cultivated at the butterfly garden to attract butterflies

A group of students from the school was at the butterfly garden, and as expected some of them were quite freaked out by the caterpillars and dared not touch them. It is a fundamental consideration when architects and landscape designers talk about biophilic design (originating from the innate tendency of humans to seek connections with nature and other forms of life) and infusing our built environment with plants (and the biodiversity that comes with them). Though biophilia is normally considered from the human perspective, a large segment of our population tends to be rather selective at what they consider as an affiliation for "all" things nature.

I had previously observed that over the past few decades, the typical Singaporean growing up in our sanitised environment and HDB apartments tend to shun the "wilder and untidier" side of nature. This may have, in certain situations, drawn a line between biophilia and biophobia. To some, if even the totally harmless butterfly can be perceived to be a "dangerous critter" to be feared and avoided, what more an ugly looking caterpillar!

The setting up of butterfly gardens in schools is a good step in the biodiversity conservation efforts in our city in a garden. More of these school gardens, together with a growing network of community butterfly gardens, park connectors, urban parks and the nature reserves will go a long way in improving our butterfly conservation efforts in Singapore. Deyi SS should be lauded for taking the extra effort to set up their own garden, and a critical success factor is the enthusiasm behind the leadership and the teachers of such schools who are key behind the success and sustainability of such butterfly gardens in school premises.

Principal of Deyi SS, Mrs Lim AP and me. :)

In any case, I was glad to be of help in the educational efforts in biodiversity conservation, in particular the appreciation and understanding of butterflies. The journey of sharing knowledge and nurturing new advocates of butterflies and their conservation in our urban greenery is a long one. But every little bit counts as we build a society that cares for the environment as much as our human aspirations for better living conditions.

Text by Khew SK : Photos by Or Cheng Khim

Special thanks to Mrs Lim AP, Principal / Deyi Secondary School and the teachers of IPSG Science Group Cluster N6, who attended the talk.  Thanks also to Tian HM and Or CK for assisting during the talk and site visit to the butterfly garden

01 April 2017

Favourite Nectaring Plants #9

Butterflies' Favourite Nectaring Plants #9
The Chinese Violet (Asystasia gangetica micrantha)

A Malay Lacewing feeds on the flower of the Chinese Violet

The feature plant in this article of our series on butterflies' favourite nectaring plants is the Chinese Violet. This tough widespread "weed" can be found in a number of habitats in Singapore, particularly in areas which have been cleared and awaiting development, or left to remain wild. It can be found growing in unkempt gardens to secondary forested areas to back-mangroves, usually as a low ground cover.

The Chinese Violet plant, with its delicated white and purple flowers

The Chinese Violet is a member of the family Acanthaceae, which features many butterfly host plants amongst the 2,500+ species in the family. The Chinese Violet is no exception, being a host plant for several Nymphalidae species like the Autumn Leaf, Blue Pansy and Great/Jacintha Eggfly. This species originated from sub-Saharan Africa, but has become naturalised in Asian countries like Singapore, where it grows rapidly in the hot humid climate.

This herbaceous plant spreads quickly and is able to climb vertically up to 1m or more, if supported. It does not appear to be particularly fussy about its substrate soils, and can appear in relatively harsh environments all across Singapore, although it prefers semi-shaded conditions to grow best. It roots easily when its stems and nodes come into contact with moist soil. Cuttings sprout white roots within 3-4 days if left in water, and the plant can easily be propagated this way.

Plant Biodata :
Family : Acanthaceae
Genus : Asystasia
Species : gangetica
Sub-species : micrantha
Synonyms : A. coromandeliana, A. intrusa, Justicia gangetica, Ruellia intrusa
Country/Region of Origin : Africa, Tropical regions
English Common Names : Chinese Violet, Common Asystasia, Creeping Foxglove, Ganges Primrose
Other Local Names : Ara Songsang, 赤边樱草, 十万错花

The paler green underside of the Chinese Violet leaf

The opposite pairs of leaves occur at right angle to each other

The green leaves are simple, opposite and decussate (successive pairs of opposite leaves occur at right angle to each other). Each leaf is ovate or heart-shaped, sparsely hairy, smooth-edged and ranges between 3 to 7.5cm long. The plant grows upright on squarish stems that have ribs and short hook-like hairs.

The flower of the Chinese Violet with the purple lower lip

The flowers are in small, one-sided racemes at the stem tips, with the flowers at the bottom of the raceme opening first. Flowers of the Chinese Violet are small and tubular, each up to 3.5cm long. There are usually 6 to 10 flowers borne on each raceme. The calyx has 5 rounded lobes, purple, vein-ridged markings on the lower lip, and 4 stamens. This species is free-flowering throughout the year. These bisexual flowers attract insects including various species of butterflies to act as pollinators in the reproduction process.

Buds, flowers and fruits of the Chinese Violet

Explosively dehiscent fruits, which come in club-shaped capsules, are initially green, but becomes brown and dry after dehiscence (3.6 cm long). The fruit resembles an upside down cello and contains 4 whitish to brownish black, circular seeds which are flattened and beaked (5 mm long, 1 mm thick). Fruits contain 3 mm-long hooks which help to propel the seeds further away from the plant during explosive dehiscence.

Ripened fruit and seeds of the Chinese Violet

In some parts of Africa, the leaves are eaten as a vegetable and used as an herbal remedy in traditional African medicine. The leaves are used in many parts of Nigeria as a traditional African medicine for the management of asthma. In Australia, this species is considered invasive and a serious threat to native ecosystems, and sightings of the Chinese Violet have to be reported to the authorities.

Flower of the Chinese Violet, where a spider tries to remain 'hidden' to wait for unwary prey coming to feed on the flower

Besides being host plant to several butterfly species, the white/violet flowers of the Chinese Violet is rather attractive to the adult butterflies. The 'universality' of the flower of this plant to butterflies is interesting, as we have seen species from 5 out of the 6 butterfly families feeding on it. With the exception of Riodinidae, representative species from Papilionidae, Pieridae, Nymphalidae, Lycaenidae and Hesperiidae have been regularly observed sipping nectar from the flowers of the Chinese Violet.

The bigger swallowtails also like to feed on the flower of the Chinese Violet

Of the Papilionidae, we have seen these larger swallowtails fluttering at the white/violet flowers of the Chinese Violet with their long proboscis extended deep into the flower. Species observed are the Common Mormon, Lime Butterfly, Common Mime, and even a Blue Helen, although it is often difficult to photograph these species moving rapidly from flower to flower with their forewings constantly flapping in the usual Papilionidae fashion.

The Grass Yellows feeding on the flower of the Chinese Violet.  Note how they have to poke their heads deep into the flower to get at the nectar within the flower.

Amongst the Pieridae, the Grass Yellows (Eurema spp.) are most often seen stopping and pushing their heads deep into the flower of the Chinese Violet. Perhaps the shorter proboscis of the smaller Grass Yellows cannot extend far enough into the flower to reach the nectar, so they need to push their heads further in to get at their liquid diet.

The Tigers and Plain Lacewing reaching into the flower to get at the nectar

The large Danainaes and Nymphalinaes from the family Nymphalidae are quite regularly spotted to feed on the nectar from the Chinese Violet flowers. As with the Pieridae, even these larger butterflies are observed to push their heads deep into the flower (often giving a "headless" butterfly shot) when their heads are out of sight whilst they feed at the flower. Species featured here include the Common Tiger, Dark Glassy Tiger, Plain Lacewing and Malay Lacewing are some examples of the Nymphalidae that feed on the Chinese Violet flowers.

The diminutive Lycaenidae are also attracted to the flower of the Chinese Violet. Being small butterflies with fine proboscis, the Lycaenidae also have to reach far into the flower to get at the nectar.

Skippers love the flower of the Chinese Violet

In the early morning hours, look for the Hesperiidae (Skippers) zipping amongst the low bushes of the Chinese Violet, reaching far into the flower with their long proboscis to feed on the nectar. From the photo records of ButterflyCircle members, it appears that a larger number of different species of Hesperiidae have been observed feeding on the flower of the Chinese Violet than any other family.

Despite being an unwanted weed found in wastelands, unkempt patches of greenery and cleared patches of sites awaiting redevelopment, the Chinese Violet is a valuable plant that is used for sustenance by Singapore's butterflies. It is a caterpillar host plant for at least 3 species of butterflies, and a nectaring plant for a good variety of species of butterflies.

So when you are out butterfly-watching, do keep a lookout for these 'white dots' amongst the low green shrubbery and ground cover - these are the pretty flowers of the Chinese Violet. Watch for the butterflies that feed on these white/violet flowers and add on to the list of species that you can see here, that use the Chinese Violet flower as a nectar source.

Text by Khew SK : Photos by Sunny Chir, Chng CK, Federick Ho, Khew SK, Loke PF, Horace Tan and Mark Wong