18 May 2019

Awls of Singapore : Part 2

Awls of Singapore : Part 2
Featuring the Awl skippers in Singapore

A Plain Banded Awl puddles on a terracotta tile floor

In Part 2 of the Awls of Singapore, we take a look at the remaining four species of skippers bearing the name "Awl" in their English Common names. As mentioned in Part 1 last week, the use of an everyday object (at least in the past) for the name of a butterfly is uncommon. The awl is, after all, a tool with a pointed tip used to make holes in leather or thick fabrics.

A White Banded Awl puddling at a concrete table

We now feature the four remaining species of the extant Awls found in Singapore - all of which belong to the genus Hasora. These are robust-bodied skippers that prefer the shaded forested areas and are usually more active in the early morning and late dusk hours of the day. They can also be found feeding on flowering plants or puddling on bird droppings and damp forest logs, footpaths and brick walls of buildings within the forested areas.

4) The Common Banded Awl (Hasora chromus chromus)

The Common Banded Awl is a relatively rare species but is widely distributed across Singapore, from the nature reserves to urban parks and gardens. It is a rapid flyer and more active in the early hours of the morning, where it zips across heavily shaded habitats, sometimes on tree trunks, feeding on the moisture of the morning dew. It can sometimes be found puddling on bird droppings, or feeding on flowers of trees like the Spicate Eugenia (Eugenia zeylanicum).

Typical behaviour of the Awls - hiding under a leaf

The upperside of the Common Banded Awl is dark brown in the male and unmarked, whilst the female has two crescentic spots on the forewings. On the underside, the base colour is a dull purple-brown with the white discal band usually narrow and outwardly diffused. The underside of the basal area of both wings is washed with a dull purple-blue sheen under certain lighting conditions. Forewing typically without an apical spot in space 6 of the forewing in the male, but in the female, there may be apical spots in spaces 6 and 7 on the forewing. The hindwing marginal white line extends indistinctly to the apex. The caterpillars have been successfully bred in Singapore on Pongamia pinnata.

5) The Plain Banded Awl (Hasora vitta vitta)

A Plain Banded Awl perched on a coconut tree trunk

The Plain Banded Awl appears very similar to the Common Banded Awl, and identification is often difficult in the field. It shares the same habits as its other cousins in that, when disturbed, it hides under a leaf with its wings folded upright. She species has been spotted at urban parks as well as in shady forested areas. A swift flyer, the Plain Banded Awl also displays crepuscular habits and regularly observed feeding at flowering trees and puddling.

Plain Banded Awls feeding on flowering plants

The Plain Banded Awl is dark brown above with a single prominent pale yellow sub-apical spot on the forewing of the male, whilst the female has additional large hyaline spots on the forewing. The underside is pale brown with the inner half of the hindwing having a bluish-grey glaze. The white post-discal band is usually broader than the Common Banded Awl. The hindwing marginal white line starts at the tornal area and generally ends at vein 3. The caterpillars have been successfully bred in Singapore on Spatholobus ferrugineus.

6) The White Banded Awl (Hasora taminatus malayana)

Like its other relatives, the White Banded Awl is mainly found in shady forested areas in the nature reserves. It also displays the habit of hiding under a leaf with its wings folded upright. Once disturbed it takes off at high speed to search for another hiding place. It is also found puddling on damp footpaths and walls of buildings in the vicinity of the nature reserves.

The male White Banded Awl is dark brown above and unmarked, whilst the female has small pale yellow post-discal spots on the forewing. The underside is pale brown with the wing bases strongly suffused with a bluish-green sheen. The white post-discal band is always narrow. The caterpillars of the White Banded Awl have been successfully bred on Derris trifoliata.

7) The Yellow Banded Awl (Hasora schoenherr chuza)

Yellow Banded Awl hiding under leaf (top) and puddling at a clay brick wall (bottom)

The Yellow Banded Awl is considered rare and usually encountered singly in the forested nature reserves of Singapore. It has the same habit of the other Hasoras of flying rapidly and then settling on the underside of a leaf to hide. It is often observed to puddle on bird droppings and other animal excretions and also fond of damp walls and tree trunks.

The Yellow Banded Awl is dark brown above with four sub-apical pale yellow spots, together with hyaline spots to form a confluent band. The hindwing has a broad yellow discal band. The underside is similarly marked but with lighter wing bases. In certain side lights, the apical and marginal areas on the underside of the wings may appear deep purple. The caterpillars of this species have been bred on Spatholobus ridleyi and Kunstleria ridleyi.

Text by Khew SK : Photos by Khew SK, Loke PF, Nelson Ong and Horace Tan.

12 May 2019

Awls of Singapore : Part 1

Awls of Singapore : Part 1
Featuring the Awl skippers in Singapore

A Orange Tailed Awl puddles on a damp timber plank

This weekend's blogpost takes a look at the various butterfly species that carry the English common name "Awl". The name Awl usually refers to a group of Hesperiidae (Skippers) that are medium-sized, robust-bodied butterflies classified under the sub-family Coeliadinae. In Singapore, the Awls come from three main genera - Badamia, Bibasis and Hasora.

A Common Awl perches in its typical under leaf pose

I did a word search to investigate the background of the name "Awl" and to look for the possible theories as to why this name was chosen for these butterflies. Invariably, the majority of online dictionaries define awl as a "A small pointed tool used for piercing holes, especially in leather." It is therefore interesting to consider why a butterfly is associated with a pointed tool for its common name!

This is what an "awl" is - a sharp tool to pierce holes in leather

Firstly, is it perhaps the broad bodies of the butterflies and sharply pointed wingtips that gave the early authors the idea that these species are reminiscent of the pointed tool? Or did these authors originally intending to name these butterflies after the bird "Owl" instead? There could always be a possibility that this name was misspelt as Awl? The group of butterflies are known to be crepuscular (active in the dim light in the dawn or dusk hours of the day), and hence could have been associated with nocturnal owls instead?

A Brown Awl extends its long proboscis to feed

It is not common to come across butterflies named after inanimate objects as its common name. In many of my discussions on the English or vernacular common names of butterflies, they are named after birds, animals, colour, people, behaviour, ranks, etc., but names after objects are few and far in between. We will never know for sure, the reasons why the early authors referred to these species as "Awls", but it can always be an interesting subject for debate!

This two-part blog article takes a look at the seven extant species of Awls in Singapore, with Part 1 showcasing three of the seven species. Amongst the butterflies called Awls, five are under the genus Hasora, and one each from the genus Badamia and Bibasis.

1) Brown Awl (Badamia exclamationis)

A Brown Awl feeding on the flower of the String Bush

The first of the Awls is a single genus-single species representative butterfly in Singapore. Globally, there are only two known species in the genus - the other being Badamia atrox, that flies in the islands of New Caledonia and Fiji. The Brown Awl has a large geographical range, starting from India at its western-most range, stretching all the way to Japan in the north-east and Australia in the south-east extremity of its range. In Singapore, the Brown Awl appears intermittently throughout the year, and can be found in the nature reserves as well as urban parks and gardens.

The Brown Awl is regularly observed hiding upside down on the undersides of leaves

The Brown Awl is a medium brown on the upperside, with elongate white hyaline streaks on the forewing in the female. These streaks are near-obscure in males of the species. The wing bases are greyish-green on the upperside. The underside is a drab greyish-brown and unmarked. The abdomen of the butterfly is striped brown and yellow. The wing shape of the Brown Awl is uniquely elongated with the hindwing strongly caudate, giving it a silhouette of a stealth bomber.

The Brown Awl is moderately rare and is usually encountered singly. It has a habit of hiding under leaves with its wings folded upright. It is skittish and a fast flyer. The species has been successfully bred on two caterpillar host plants in Singapore - Combretum sundaicum and Terminalia calamansanai.

2) The Orange Tailed Awl (Bibasis sena uniformis)

An Orange Tailed Awl puddling at a sandy streambank

The Orange Tailed Awl is rare, and a new discovery for Singapore when it was first observed in the forested nature reserves of Singapore. Subsequently, the caterpillars of the species were found in numbers in the Singapore Botanic Gardens on Hiptage benghalensis. However, the adult butterflies are still rarely seen, perhaps due to its crepuscular habits.

The Orange Tailed Awl is dark brown on its uppersides and unmarked. The wings are long and angular with the hindwing tornal cilia a deep orange yellow in pristine individuals. The underside has a broad white discal band on both wings and a purple-blue sheen. The hairs on the legs of the butterfly are orange yellow.

3) The Common Awl (Hasora badra badra)

A Common Awl perches on the underside of a palm frond

The Common Awl is a relatively widespread species in Singapore, and has been observed in urban parks and gardens as well as the forested nature reserves. It is one of five species in the genus Hasora. It is also closely associated with the mangrove and back-mangrove environments where its caterpillar host plant, Derris elliptica, grows wild as a creeper. It tends to prefer shaded habitats and has a habit of flying rapidly and then settling with its wings folded upright on the underside of a leaf to hide itself.

The Common Awl is often encountered puddling at footpaths, bird droppings, damp tree trunks and in the case of the last photo, even on damp brick walls!

The male Common Awl is dark brown above with the wings usually unmarked, although in some individuals, small sub-apical spots may be present. The female has three large pale yellowish sub-apical spots and large hyaline spots in the cell area of the forewing. The underside is brown with a light purplish glaze with a prominent circular white spot in the cell of the hindwing. When photographed with a flash, the purple glaze is enhanced, bringing out a strong purple blue sheen that is not usually seen in natural light.

In the next part of the Awls of Singapore, we take a look at the remaining four Awls that are extant in Singapore, all of which belong to the genus Hasora.

Text by Khew SK : Photos by David Chan, Khew SK, Koh CH, Michael Soh, Jonathan Soong and Horace Tan

05 May 2019

Butterfly of the Month - May 2019

Butterfly of the Month - May 2019
The Chestnut Angle (Odontoptilum angulatum angulatum)

A Chestnut Angle perches on a leaf with its wings opened flat - typical with the Pyrginae skippers

The fifth month of 2019 is upon us, as we continue to march forward into the year. For those of us inundated with the constant tsunami of information on social and mainstream media, the wide spectrum of news affecting local and global issues continue to influence us in unexpected ways. From climate change and terrorism to politics and harassment, the world moves at a much faster pace when news is literally at your fingertips.

The launch of the Draft Masterplan 2019 by the Urban Redevelopment Authority (URA) in Singapore also brings visions of where Singapore wants to be in the coming decades. As land is scarce in our little 720 sq km island (and will continue to be more so as the city state develops), what does the future hold for the population as it grows?

Chestnut Angles are often seen puddling on damp footpaths and stream banks

The concern for climate change/global warming/resources stress continues (more so for some countries than others). But we share the same earth. It is unthinkable to consider that the climate issues that affect one country has nothing to do with another. For example, there is already compelling evidence that the polar ice has begun to melt like no other period in modern history. This simulation shows what the world would look like if all the ice melted. What can we do about it?

And then in a fantasy world that takes us away from reality, the launch of Avengers : EndGame created enough buzz across the globe to distract some of us, some of the time. From our real-world 'struggles' that we face daily, we take some time out and enjoy the world of superheros and vile villians out to end the universe.

Over in Singapore, a sexual harassment incident in a university hall of residence created enough social media buzz for a period of time. The victim took to cyberspace when she felt that the punishment for the perpetrator was presumably inadequate. The incident, as it was played out on social media, prompted debate on two fronts - one was the way sexual harassment was dealt with by an academic organisation, and on the other side, the vigilantism that occurs on social media that threatens the fabric of any justice system.

The often-asked question locally - "will the elections be held this year or not ah?" tends to underscore our views on the importance of stability of our little red dot. Political stability and quality of the leadership are important ingredients of the economic sustainability, well-being and progress of a country. Hence any news, speculation and hints about the political future of Singapore is always fodder for coffeeshop talk and chatter.

Our feature butterfly for May 2019 is one of the 'flats' from the subfamily Pyrginae of the skipper family Hesperiidae. This subfamily hosts the various genera of butterflies that are collectively called "Spread-winged skippers". The characteristic open winged pose of these skippers probably gave rise to their common names. However, this month's butterfly, the Chestnut Angle (Odontoptilum angulatum angulatum) departs from the usual "flat" in its name but is christened an "angle", probably due to its more angled appearance. Its latin name angulatum yields the definition : made angular/cornered, with angles, angular.

A Chestnut Angle feeding on the Spanish Needle flower.  Even when feeding, it keeps its wings opened flat

The Chestnut Angle is considered a moderately rare species in Singapore, but is regularly seen singly in urban parks and gardens, as well as in the forested nature reserves. It is a skittish butterfly, and flies rapidly and erratically. However, when it is puddling on sandy streambanks, or stops to rest to sunbathe, it is not difficult to approach it.

Under certain conditions (e.g. very hot sunshine) a puddling Chestnut Angle may close its wings upright

When disturbed or on hot days when it stops to rest, it displays the typical habit of the Pyrginae - stopping on the undersides of leaves with its wings opened flat. In Singapore, it can also be encountered on the landward edges of mangrove areas where one of its host plants, Sea Hibiscus  (Hibiscus tilaceus/Talipariti tiliaceum) can be found. It has been successfully bred locally on Commersonia bartramia, which appears to be its preferred caterpillar host plant in urban parks and nature reserves.

A typical under-leaf pose, where the hyaline apical and crescent shaped spot can be seen clearly in a blacklight

The forewing termen of the Chestnut Angle is sinous and a prominent angular step at vein 7 of the hindwing, giving it a rather angular appearance. The upperside of the butterfly is chestnut brown, with a complex cryptic pattern on dark and lighter patches on the forewing, and white lines on the hindwing. There are several hyaline spots on the forewing, and a characteristic crescent-shaped spot on the forewing.

An uncommon pose of a Chestnut Angle where it closes its wings upright to show its undersides

The hindwing has elongated cilia, particularly at the tornal area. On the underside, the hindwing is predominantly white with large brown spots at the tornal and apical areas. The forewing is also whitened at the base with the apical and subapical area a dark brown. The body of the butterfly is white when viewed from the underside, whereas it is brown dorsally except for the abdominal tip.

Text by Khew SK : Photos by Khew SK, Lim CA, Loh MY, Michael Soh, Jonathan Soong, Horace Tan and Bene Tay

28 April 2019

Flying Flowers

Flying Flowers
SG Butterflies named after Flowers

A Common Rose sunbathes with its wings opened flat on a leaf

Colourful butterflies fluttering around in gardens are often admired by one and all. Their beauty, grace and gentleness as they fly from flower to flower, feeding on nectar with their long proboscis have long been associated with the wonders of Mother Nature's creations. By themselves, the intricate patterns and colourful wings of butterflies are often referred to "flying flowers".

A male Blue Pansy showing off its colourful wings

In this weekend's blog post, we take a look at the common English names of butterflies in Singapore, and how many species are named after flowers. In an earlier blog post, we investigated the backgrounds of some of the common names that were coined for butterflies by the early collectors. Whilst common names are usually avoided by taxonomists and scientists, we often find that hobbyists and amateur naturalists tend to use vernacular names for easier reference.

A Common Posy feeding on the sap of the Bandicoot Berry, surrounded by ants

Of the 330+ species of butterflies found in Singapore, only nine are named after flowers, or words specifically associated with flowers. All nine are resident natives species found in Singapore, and the species can be collectively placed under four groups named after flowers.

The Common Rose

A typical red cultivar of a Rose

This Swallowtail butterfly is the first of the species to be named after a flower - the rose. A rose is the flower of a woody perennial flowering plant of the genus Rosa, in the family Rosaceae. There are over 300 species of roses and thousands of cultivars ranging in colour from black to red and whites and yellows. Roses are well-known as bouquets for displays or gifts of affection and love.

Subspecies asteris of the Common Rose that is found in Singapore and Malaysia

The Common Rose is a resident species of Southeast Asia, of which there are at least 20 known sub-species occurring geographically from Sri Lanka and eastwards to the Philippines. The local sub-species found in Singapore and Malaysia is asteris and is the only extant Papilionidae in Singapore to be named after a flower.

Possible subspecies antiphus or even a valid species from Borneo?

There was a period around 2004 - 2009 where a variant of the Common Rose appeared in Singapore. This lacked the large white spots on the hindwing of the butterfly. This "Black Rose" seemed to resemble the Bornean species Papilio antiphus or which some have classified as a subspecies antiphus of the Common Rose, Pachliopta aristolochiae. However, in recent years, this strange Black Rose has not been seen in Singapore.

The Pansy Butterflies

Various hybrids of the Garden Pansy (Viola wittrockiana) in bloom

The Garden Pansy is a type of large-flowered hybrid plant cultivated as a garden flower. The hybrid is often referred to as Viola wittrockiana derived chiefly from the hybridization of the European Johnny-jump-up (Viola tricolor) with other wild violets. Modern horticulturists have developed a wide range of pansy flower colors and bicolors including yellow, gold, orange, purple, violet, red, white, and even near-black (very dark purple).

The Four Pansy butterflies found in Singapore - Peacock, Blue, Chocolate and Grey

The Pansy butterflies are collectively grouped under the genus Junonia. Of these, four species - the Blue, Chocolate, Peacock and Grey Pansys occur in Singapore. These are generally sun-loving butterflies and are usually found in urban parks and gardens in sunlit grassy areas.

All the Pansy butterflies feature eyespots (or ocelli) on their wings and amongst the four resident species, the Blue and Peacock Pansy are brightly coloured and considered the prettiest amongst the four species. The Chocolate Pansy, although more drably coloured, is also an attractive butterfly, with its reddish eye spots. It is by far the commonest of the four.

The last species, the Grey Pansy, may be seasonally common but is the rarest of the four species in Singapore. With a violet-grey ground colour on both wings, the Grey Pansy also features a series of orange-crowned black ocelli across the submarginal area of both wings.

The Posy Butterflies

A Posy of flowers - usually referring to a bouquet of colourful flowers or even a wreath

The word "Posy" is often used to refer to an arrangement or bouquet of colourful flowers presented as a gift. Whilst a Posy does not refer to any specific species of flowers, the word is associated with a decorative arrangement of colourful flowers.

A male Dark Posy resting on a leaf

There are 3 species of butterflies that are collectively grouped under the common name of "Posy". These species, under the genus Drupadia of the family Lycaenidae, are small forest-dependent species. All 3 species look rather similar, although they can be separated by distinctive markings on the wings.

The three Posy butterflies found in Singapore - Common, Dark and Pygmy

Of the 3, the Common Posy (Drupadia ravindra moorei) is most regularly encountered in the forested nature areas in Singapore. The Dark Posy is less often seen but generally encountered in the same localities as its commoner cousin. The last species, the Pygmy Posy, distinctive in its diminutive size and thicker markings, is the rarest of the 3 and not often encountered.

The Forget-Me-Not Butterflies

A cluster of blue True Forget-Me-Not flowers

The True or Water Forget-Me-Not flower (Myosotis scorpioides) grows on tall, hairy stems which can sometimes reach up to 70 cm in height. The plant bears small (8-12 mm) flowers pink in bud, becoming blue when fully open, with yellow centers and white honey guides. The plant is native to Europe and Asia although it is considered an introduced invasive weed in certain countries.

Our Forget-Me-Not butterflies in Singapore - (top)- Silver Forget-Me-Not and (bottom) Forget-Me-Not

There are two species of butterflies called "Forget-Me-Not" - these are the Silver Forget-Me-Not (Catochrysops panormus exiguus) and Forget-Me-Not (Catochrysops strabo strabo). Their English common names were perhaps coined for these species due to their pale blue uppersides that resemble the Forget-Me-Not flowers.

Both species may be considered moderately rare, but appearing to be common in certain localised areas seasonally. They are difficult to distinguish in the field, except when the underside of the forewing's costal spot can be seen. Both species are widely distributed in Singapore, and they can be spotted in urban parks and gardens, and also in forested areas near the mangroves.

Text by Khew SK : Photos by Bob Cheong, Khew SK and Loh MY