25 October 2020

Bush Browns of Singapore : Part 1

Bush Browns of Singapore : Part 1
Featuring the Mycalesis species of Singapore

A female Dingy Bush Brown (Mycalesis perseus cepheus) perches on a moss-covered tree root

The genus Mycalesis, collectively known by their English Common Name of "Bush Browns" is represented by six species in Singapore. The majority of the species are moderately common except for one which is mainly found in forested areas of the nature reserves. In this two-part blog post, we take a look at these Bush Browns that can be found in Singapore.

A Malayan Bush Brown (Mycalesis fusca fusca) perches on a leaf

The Bush Browns are members of the sub-family Satyrinae, usually referred to as "Browns and Arguses" Predominantly brown in colour, all the species of the Bush Browns are adorned with submarginal ocelli (eyespots) on the underside of both the fore and hindwings. As they belong to the family Nymphalidae, their forelegs are under-developed, and all the species stand on the mid- and hindlegs only.

A Purple Bush Brown (Mycalesis orseis nautilus) perches on a leaf

They typically fly in grassy habitats (of which several species' caterpillars feed on as host plants), and fly low amongst the grasses and shrubbery. Their flight is generally weak but they are alert and skittish, and are often quite challenging to photograph. The Bush Browns typically rest with their wings folded upright, although some of the species have been observed to open their wings to sunbathe at certain hours of the day.

A Malayan Bush Brown (Mycalesis fusca fusca) perches on a fern

This weekend's article introduces the three more distinct species that are easier to identify in the field. In next week's article, we will take a look at the more cryptic lookalikes that will require a bit more scrutiny to correctly identify them.

1. The Malayan Bush Brown (Mycalesis fusca fusca)

A Malayan Bush Brown feeding on the ripened fruit of the Singapore Rhododendron
An uncommon shot of the upperside of the Malayan Bush Brown

The Malayan Bush Brown is the most distinctive of the six species currently found in Singapore. It is usually found in forested areas and along the fringes of the nature reserves flying amongst low bushes and grasses, particularly where its caterpillar host plant, Scleria bancana grows.

The Malayan Bush Brown is the only orangey-brown species that occurs in Singapore. It has a pair of reddish-brown longitudinal stripes on both wings. The orange ringed sub-marginal ocelli are distinctive and the Malayan Bush Brown cannot be confused with any of the other species found in Singapore. The upperside is brown with obscure ocelli.

2. The Purple Bush Brown (Mycalesis orseis nautilus)

A Purple Bush Brown (Mycalesis orseis nautilus) with its full set of yellow-ringed ocelli on both wings

The Purple Bush Brown is the rarest of all the Bush Brown species in Singapore. It is a predominantly forest species and is rarely found outside the sanctuary of the shaded nature reserves. Its caterpillar host plant is currently unknown, but is likely to be one of the grasses. It is usually found singly and flies low amongst grassy undergrowth in shaded habitats.

The yellow-ringed submarginal ocelli on the underside of the fore- and hindwings are rather uniform in size and the majority of the ocelli are touching the adjacent ocelli. The broad white post-discal band that stretches across both wings is faintly violet-washed in a side light.

3. The Dingy Bush Brown (Mycalesis perseus cepheus)

The Dingy Bush Brown is easily distinguished from the other lookalike species in the genus in that the ocellus in space 2 of the hindwing is moved inwards and out of line with the other ocelli adjacent to it. The species also usually has a full set of four ocelli on the underside of the forewing. The caterpillar of this species has been bred on the common "Cow Grass" (Axonopus compressus) and most certainly some other species of grasses.

A courting pair of Dingy Bush Brown.  Male - Left, Female - Right

The species is found amongst grassy areas around the fringes of the nature reserves and buffer parks. The males are generally darker brown than the females. The species has a widespread distribution across Singapore, but cannot be considered common. In localised areas, it can regularly be spotted flying around, and sometimes several individuals can be seen together.

Text by Khew SK : Photos by Khew SK and Tan BJ

18 October 2020

Butterfly of the Month - October 2020

Butterfly of the Month - October 2020
The Bush Hopper (Ampittia dioscorides camertes)

A Bush Hopper perched on a grass blade

We trudge cautiously towards the end of 2020, not knowing what is around the corner in a year that has thrown so many unpleasant surprises at us. For once, there is a universal acceptance of each country's unique misfortunes whenever the word "pandemic" is mentioned. Everyone will nod with complete understanding of the situation, as the whole world probably knows the word COVID-19 by now and the havoc it has wreaked on everyones' lives.

The situation in Singapore appears to have turned the corner, as the number of infections in the community has fallen to single digits for a few days now. But that is because our little island is still very much "locked" down, with minimal travel into Singapore, and strict measures in place for community interactions. Life has take a very different outlook now, as wearing a face mask has become the default for everyone, whenever we step outside our homes.

But nothing can be taken for granted on a very compact island where residents are "crammed" into a 720 sq km island, and where the population density per sq m is one of the highest in the world. Like many countries that have somewhat managed to contain the pandemic to low numbers of infections, the prospects of borders re-opening and inter-country travels start again will be something to watch out for, and be concerned about.

A Bush Hopper perched on a grass flower

Our outdoor spaces like parks and nature areas in Singapore are more heavily used than I can ever remember in recent times. Even the outlying parks that are usually peaceful and quiet are seeing unprecedented visitorship with local residents thronging these public amenities as travel is curtailed and most residents are looking for new places to go to get their fair dose of fresh air and sunshine.

As we move into a much-anticipated "Phase 3" of the progressive easing of the safety measures, residents are looking forward to a new norm of social interaction, with lots of controls in place to minimise cross-infections in the community. But with every policy, every procedure is a learning journey, and things will continue to evolve and residents will have to adjust to the life with COVID-19 in our midst.

A Bush Hopper feeding at the purple flower of Duranta sp

Our Butterfly of the Month for October 2020 is a tiny inconspicuous skipper from the sub-family Hesperiinae. The Bush Hopper (Ampittia dioscorides camertes) is a predominantly orange-and-black skipper that has a wingspan that rarely exceeds 20mm across from wingtip to wingtip. Whilst it is considered only moderately common, it can be found quite regularly in its preferred habitats of grassy open areas in urban parks and gardens.

The Bush Hopper is a small butterfly, and may often be missed by observers due to its diminutive size. It flies rapidly, and is usually seen in the company of other skippers like the Lesser Dart and Small Branded Swift in urban parks. Whilst it stops with its wings in the usual skipper pose, it has an interesting behaviour of keeping its wings in motion, opening and closing its wings when it perches to rest, unlike the similar looking Darts (or Potanthus spp).

The male Bush Hopper (top) has more extensive orange markings on the uppersides whilst the female (bottom) is more brown in appearance with reduced orange-beige spots

The male Bush Hopper is dark brown with generous orange-yellow markings above. The orange markings are arranged with a broad stripe in the cell and large conjoined subapical and postdiscal spots. The paler brown female has smaller and much reduced spots on her wings, and the spots are generally lighter orange in colour.

The underside is light orange-brown with the markings giving a more chequered appearance, especially on the hindwings. In pristine individuals, the cilia on the margins of both wings are chequered. The antennae lacks the typical prominent apiculus (or hook at the clubbed tip of the antennae) such that the Bush Hopper almost resembles the Taractrocera genus of skippers.

Occasionally, male Bush Hoppers are observed to puddle at damp sandy streambanks in the nature reserves

From field observations, males of the Bush Hopper occasionally puddle at damp sandy spots along forest paths and streams - a behaviour that is rarely displayed by the related skippers like the Lesser Dart and other Potanthus species. When puddling, it also opens and closes its wings, a habit that is quite unique to the Bush Hoppers.

A courting pair of Bush Hoppers. Female (Left) and Male (Right)

Although its life history has not yet been successfully documented yet, its caterpillars are highly likely to feed on common species of grasses (Poaceae) found in areas where the butterfly is often seen - sometimes in numbers. Both the males and females are equally common in localised areas where they are observed.

Text by Khew SK : Photos by Khew SK and Loh MY

11 October 2020

1000 - A Milestone

1000 Posts - A Milestone
Thirteen Years of Blogging

A male Cornelian (Deudorix epijarbas cinnabarus) sunbathes on a blade of grass

Over 13 years ago, I benefitted much from the knowledge shared by fellow nature enthusiasts in Singapore. Back then, when social media, influencers and blogging were less pervasive than it is today, I enjoyed the stories and information shared by a few active nature bloggers and friends in the Singapore nature community. Amongst these bloggers were Ria Tan, Dr Wee Yeow Chin, November Tan and Marcus Ng. I often followed their blog articles which were always inspiring and promoted nature appreciation across a myriad of topics from the terrestrial to the marine world.

Wild Shores of Singapore Blog by Ria Tan - one of Singapore's most prolific Nature Bloggers

Ria, who started her Wild Singapore Blog and portals to feature the marine, intertidal and to a lesser extent, terrestrial news by various local enthusiasts, became a hub for nature news in Singapore. Her own personal blog, Wild Shores of Singapore, continues to this day. The main portal, Wild Happenings In Singapore, which functions like a calendar of local nature happenings, has now been shut down.

Another friend, November Tan, also persuaded me to share information about butterflies when I was invited to her now-retired series of workshops to educate like-minded and interested parties about various aspects of nature in Singapore. She used to blog via her Leaf Monkey Workshop portal, through which she energetically promoted nature through fun and humorous workshops.

The now-retired Bird Ecology Study Group by Dr Wee Yeow Chin - nearly 25 million visits to the blog and a popular resource in the international birding scene

Dr Wee, who is a prominent author and botanist by training, took up the mantle of bird watching and started his own observations on his blog, which evolved in his Bird Ecology Study Group. Dr Wee's blog was a huge influencer in bringing the bird watching community from just recording sightings of birds, locations and numbers to observing their behaviour in the field in specific habitats and place more emphasis on the ecological study of birds in the region. Unfortunately, due to health and other commitments, Dr Wee ended his internationally popular blog at the end of 2019.

A newly-recorded species in 2020 - The Swamp Tiger was spotted on Butterfly Hill at Pulau Ubin

Then there was "Budak" Marcus Ng with his Annotated Budak blog (last post in 2015), fellow ButterflyCircle member Federick Ho with his "Beauty of Flora and Fauna in Nature" blog (which has intermittent posts and is still active), Debby Ng's Hantu Bloggers (active blog today) and many others.

A male Banded Royal perches on the red flowers of Ixora sp

Prior to joining the blogging community, I had a website created back in 2004 just to post information about butterflies. Back then, another internet veteran, Chin Fah Shin, was an inspiration with his website about Malaysian butterflies which he started way back in 1998! I also observed that there were not many websites dedicated to information about butterflies back then, and I thought that it would be useful to jump on to the blogging bandwagon and see where it takes me.

Butterflies of Singapore Blog 2007-2020 and the 999th article on the blog

I researched on various blogging platforms back then, looking at software like Blogger (now owned by Google), WordPress, and other easy-to-set-up-and-use software. The most popular back then was Blogger, so I tried it and found it much easier than managing a website that I did in the past, where I had to learn a bit of HTML coding and organising the information. So I dabbled around with it and posted my first blogpost on 16 Aug 2007. A comment on that post by Dr Wee still resonated with me. He wisely said "knowledge not shared is knowledge lost."

And that's how it all started. Thirteen years in the making. Although not as prolific in posting almost daily, as Dr Wee did in his heydays on BESG, I organised my thoughts across various topics relating to butterflies - ranging from photography, life histories, habitats, plants, community engagement, education, publications, taxonomy and morphology, locations, travelogues, and many other categories.

Looking around the blogging scene back then in 2007, many others started their own blogs, but few had the stamina to last more than a few months. Most fizzled out after the initial novelty of having a blog to their own name wore off. Others just ran out of steam. At the end of the day, it's still a personal commitment to share information and knowledge.  Other than a handful of blogs which attracted business opportunities, there is no commercial gain nor benefit from such a past time.

Members of ButterflyCircle on an overseas outing

I was fortunate that ButterflyCircle was formed three years earlier in 2004, and there were many friends and enthusiasts who were out regularly to record butterflies in the field - both locally and overseas. This provided a good source of information and material for blogposts, and ideas for articles that were spun off a few pictures or observations. This continued through the years, and I am thankful to all these friends and fellow-photographers who helped make this blog more "colourful" and to showcase their good work.

Examples of Horace's masterpieces on Life Histories of Singapore's Butterflies

Then there were those who also contributed articles that added to the diversity of knowledge on this blog. I have to specially mention Horace Tan, who is the life-histories expert behind all the excellently documented articles here. To date, there is a total of 197 life history (and more to come!) documentation of Singapore's butterflies on this blog, and this valuable repository of information far exceeds what anyone else has done for Singapore's butterfly early stages' research. Horace then followed up with his caterpillar host plants series of articles, penning a further 14 articles.

And so this blog has passed its 1000th post milestone. And that's done with at least one blogpost per week, for the past 13 years! With the advent of more convenient platforms on social media like FaceBook groups, Instagram and so on, it is much easier to share information across the world today. Posts are usually more concise, and a large majority of posts tend to be short 1-minute reads. Anything longer is likely to be skipped.

Is a blog still relevant to the way people consume news and knowledge today? Are there other more efficient and productive ways of reaching out? Many questions posed food for thought to me. But like Dr Wee, Ria and the other friends who have stood the test of time and endured for many years with their informative nature articles, perhaps it is time to take a rest and let the younger generation take on the next lap.

Briefing Deputy Prime Minister Heng at Butterfly Hill on Ubin Day 2020

This blog will continue for the remaining months of 2020, in the same way that it has churned out a-week-a-post for the past 13 years. The new year 2021 will see a reduction in the number of articles per month and may be more ad hoc and intermittent in terms of information sharing. I would like to express my deepest appreciation to those who have contributed to this blog in one way or another, and all our readers out there who have enjoyed and appreciated the research and work put into each of these articles since 2007.

Text by Khew SK : Photos by Khew SK, NParks and Horace Tan

04 October 2020

Tigers, Crows and the Rattlebox Plant

Tigers, Crows and the Rattlebox Plant
Leaf Scratching Behaviour in Danainae Butterflies

A Black Veined Tiger feeding on the secretions from the young flower buds of the Rattlebox Plant

The Danainae butterflies, often referred to as the "Tigers and Crows" are known to be attracted to some plants to sequester chemical substances to aid in biosynthesis of a pheremone component. These pheromones in the males are used for attracting females in courtship, and the eventual process of mating and procreation.

A Dark Glassy Tiger feeding on the secretions from the yellow flower of the Rattlebox Plant

Plants in the families Boraginaceae, Asteraceae and Fabaceae are usually targeted by adult Danainae butterflies for a particular chemical substance called pyrrolizidine alkaloid (or PA). These "Tigers and Crows" have previously been recognised by the early authors to be attracted to the dried leaves of Heliotropium indicum (Boraginaceae) which is often used to attract these butterflies for collection purposes.

A male Common Tiger feeding on the secretions from a young flower bud of the Rattlebox Plant

In the "Butterflies of the Malay Peninsula" 4th Edition, the authors noted that "In courtship, the correct sequence of dispersal of the male pheremones by the abdominal hair pencils must be followed before successful mating can take place... additional pryrrolizidine alkaloids have to be imbibed by the adult males, both from nectar and from withered or damaged plants. Droplets of fluid are regurgitated onto the plant and then reimbibed."

A Spotted Black Crow feeding on the sap after scratching the surface of a pea pod of the Rattlebox Plant

The authors of "Butterflies of Hong Kong" also observed this behaviour of the Danainae using their midtarsi claws to scratch the "soft surfaces of the leaves, stems, calyx cups, pod stalks, and damaged areas and the exuding sap is greedily imbibed, the proboscis moving about in an agitated manner." It was also observed that in Hong Kong, although there are 8 species of Crotalaria, the Danainae fed in this manner on only C. retusa."

A Common Tiger (Danaus genutia genutia) displaying plant-scratching behaviour on the flower bud of the Rattlebox Plant (Crotalaria retusa). Click to play video.

The same plant-scratching behaviour has also been observed many times in Singapore and Malaysia. The presence of the Rattlebox Plant (Crotalaria retusa) (Fabaceae) in a garden or park, has often attracted a variety of different Tigers and Crows to display this behaviour. At times, up to a dozen or more individuals of different species of Danainae have been observed congregated at a single plant, feeding on various parts of the Rattlebox Plant from the buds to the seed pods.

Over years of observations of this plant-scratching behaviour by Danainae species, we have recorded at least nine different species of the Tigers and Crows feeding at Crotalaria retusa. Whilst some Danainae species do not stay as long as others, there is obviously a need for these species to feed on the chemicals that are present on various parts of this plant - from the flowers to leaves and seed pods.

A female Striped Blue Crow joins in the search for the alkaloids from the Rattlebox Plant

Interestingly, a female Striped Blue Crow (Euploea mulciber mulciber) was also observed to feed on the sap from the stem of a seed pod of the plant. Was she looking for PAs as well? Or was it some other chemical substance in the fluid of the plant that she is searching for? Or do females also need to sequester PAs for other biological functions that have yet to be ascertained?

A "crowd" of Dark Glassy Tigers on the young flower buds of a Rattlebox Plant
A Dark Glassy Tiger feeding on the sap from ripened pea pods of the Rattlebox Plant
A Dark Glassy Tiger feeding on the sap of the seed pod of the Rattlebox Plant. Note the scratch marks on the seed pod caused by the sharp tarsal claws of the butterfly
A Dark Glassy Tiger feeding on the sap of a damaged young pea pod of the Rattlebox Plant

Amongst the Danainae, the most often-encountered species that displays the "plant-scratch and feeding" behaviour is the Dark Glassy Tiger (Parantica agleoides agleoides). They seem to be very quickly attracted to the Rattlebox Plant whenever this plant is available at our parks and gardens, and in some instances, many individuals are observed, congregated on the plant and feeding greedily.

A Common Tiger exhibiting the leaf-scratching behaviour on the Rattlebox Plant. Click to play video

The Common Tiger (Danaus genutia genutia) is almost equally often encountered feeding (compared to the Dark Glassy Tiger) on the damaged parts of the Rattlebox Plant, particularly after some vigorous scratching by the butterflies. There have been observations of the Common Tiger feeding on various parts of the Rattlebox Plant, both with and without the scratching behaviour.  In some cases, the butterfly merely fed on the moisture from the leaves or flower buds of the plant.

How many Common Tigers can you count on this Rattlebox Plant?

In one observation at Coney Island Park at a damaged Rattlebox Plant, there were at least 11 Common Tigers feeding and fluttering restlessly around the plant, vying for and nudging each other in competing for the best spot to imbibe the PA.

A Black Veined Tiger feeding on the damaged young shoots of the Rattlebox Plant. Click to play video

The similar-looking Black Veined Tiger (Danaus melanippus hegesippus) is another Danainae that is regularly seen around the Rattlebox Plants. The species was recorded on this video showing an individual feeding on the damaged young shoots of the plant. In other observations, the Black Veined Tigers have been seen to be feeding on the undamaged young flower buds of the Rattlebox Plant.

A gathering of Tigers and Crows at the Rattlebox Plant at Pulau Ubin's Butterfly Hill

The closely-related and equally common Plain Tiger has been observed at the plant, although not as often nor in as large numbers as the Common Tiger. Other less common Danainaes like the Spotted Black Crow (Euploea crameri bremeri), the Dwarf Crow (Euploea tulliolus ledereri), the King Crow (Euploea phaenareta castelnaui) and the Striped Black Crow (Euploea eyndhovii gardeneri) are occasionally spotted feeding on various parts of the Rattlebox Plant.

The Rattlebox Plant is a useful addition in urban parks and gardens, and certainly in dedicated butterfly gardens. Despite being sometimes considered a "weed", its attractive green foliage and bright yellow flowers makes it a pretty plant for a landscaped garden. It is considered one of those "butterfly magnets", especially for the leaf-scratching Danainae butterflies. The plant is also a caterpillar host plant for the Pea Blue (Lampides boeticus).

Text by Khew SK : Photos by Khew SK, Michael Soh, Tea Yi Kai and Yeo Chew Kheang.