Butterfly of the Month - April 2024

Butterfly of the Month - April 2024

The Brown Awl (Badamia exclamationis)

It has been a very hot hot April, with temperatures in Singapore soaring in the high 30's. All over Asia, temperatures are at an unprecedented high, and we are not even in the summer months yet! If this is not climate change, then I don't know what is. Historical highs are being recorded year after year and it is quite widely acknowledged by butterfly watchers and enthusiasts that butterfly populations are down in many parts of Asia, compared to a decade ago.

This month, our feature butterfly is the unremarkable Brown Awl (Badamia exclamationis). This is a skipper from the sub-family Coeliadinae and the only representative of its genus in the region. It is a relatively large butterfly and is a fast-flyer like most Hesperiidae species. I've always been intrigued by the latin species name of this Skipper. It's as though the scientist who first described it screamed out loud when he first discovered this butterfly!

The Brown Awl is moderately rare in Singapore, usually observed singly in the early hours of the morning. It has also been observed to puddle occasionally, but where it is encountered, it is more often seen feeding on moisture off damp rocks, stone walls and timber structures in the cooler morning air. There have been few records of the Brown Awl feeding on flowers.

The species is more often encountered in the forested nature reserves than in urban parks and gardens, although it is widely distributed across Singapore and found in various habitats where its caterpillar host plants, Combretum sundaicum and Terminalia calamansanai (both from the Combretaceae family) are found. Where they are observed, they are usually encountered singly.

A Brown Awl perched on a damp rock after feeding off moisture from the rock

A Brown Awl feeding on the flower of the String Bush at Tampines Eco Green

The wings of the Brown Awl are very elongated and the hindwing is caudate at vein 1b, and strongly excavate between veins 1b and 2. Above, the wings are dark brown with greyish green scaling at the wing bases. The female has prominent and elongated hyaline streaks in spaces 1b, 2 and 3, and the cell in the forewing. In contrast, these streaks in the male are rather small and subdued.

A partial upperside view of a male Brown Awl

On the undersides, both sexes are pale greyish brown and largely unmarked. There is a small yellowish sub-tornal spot in space 1b of the hindwing, which usually goes unnoticed as the hindwings typically fold up at the dorsal area. The prominent veins on the underside gives the butterfly a streaked-like appearance. The abdomen of the butterfly is prominently yellow-banded.

Under leaf behaviour of the Brown Awl where it clings on to the underside of a leaf to rest

The Brown Awl occurs from Sri Lanka, India, China through the Malay Peninsula and Singapore to New Guinea, Australia and as far east as Samoa. In Singapore, it is usually encountered feeding at damp rocks or at flowering plants (uncommonly). It has a habit of perching on the undersides of foliage with its wings folded upright and often adopts this position when it is disturbed and flies off to hide under a leaf.

Text by Khew SK : Photos by Khew SK, Koh CH, Dr Lee PC, Billy Oh, Jonathan Soong and Horace Tan

Butterfly of the Month - March 2024

Butterfly of the Month - March 2024

The Indigo Flash (Rapala varuna orseis)

A pristine female Indigo Flash perches on a dew covered grass blade in the early morning hours. Note the slight purplish wash on the wing bases.

March 2024 has whizzed past in a flash, and on this final day of the month, we feature one of our "Flash" butterflies that exists in Singapore. A butterfly that belongs to the Lycaenidae family, called the "Blues and Hairstreaks", these species found in Singapore are mainly classified under the genus Rapala. The Flash butterflies are fast-flying skittish species and are difficult to spot when they flash from perch to perch.

Our feature butterfly for March 2024 is the Indigo Flash (Rapala varuna orseis). It is one of nine extant species from the genus Rapala that have been found in Singapore. Only recently, the early stages of the species were recorded on the local caterpillar host plant, Bridelia tomentosa. The Indigo Flash is often encountered in urban parks and gardens as well as within the nature reserves of Singapore.

The species is skittish and is usually quite alert. It is widely distributed across Singapore, where it is regularly encountered singly but at times more than one individual is spotted in the same location. At certain hours of the day, both sexes are sometimes observed perched on the uppersides of leaves with their wings opened almost flat to sunbathe.

Upside-down behaviour of both sexes of the Indigo Flash where the butterfly perches upside down on leaves and stems

It is sometimes encountered feeding on flowering plants and weeds like Mile-A-Minute, Spanish Needle and Stringbush. When it is resting in the shade, the Indigo Flash sometimes displays an upside-down behaviour where it perches on the undersides of leaves to rest. Both males and females are observed to behave this way.

A female Indigo Flash perched with open wings to sunbathe

A male Indigo Flash showing a glimpse of its deep indigo-blue upperside 

The Indigo Flash belongs to the varuna group of the genus Rapala, where the males and females are a shade of blue or bluish-green on the upperside. Males of the Indigo Flash is indigo blue above and unmarked, whilst females are steely blue and also unmarked. The underside is dark brown in the male and is strongly purple-washed. The female is a lighter brown and usually lacks the purple wash found in the males.

The post discal bands are white-edged, and broader than usual compared to other species in the genus, and darker than the ground colour of the underside. There is a large orange-crowned eyespot at the tornal area of the hindwing, with iridescent blue-green scales adjacent to it. On the hindwing, the cell-end bar is angled towards the post-discal band and closer, often touching each other. There is a white-tipped black filamentous tail at vein 2 of the hindwing.

Note the circular disc on the underside of the hindwing that houses the scent brand in the male Indigo Flash

The eyes of the Indigo Flash are jet-black and smooth. The legs are black-banded. The antennae are also black-banded and orange-tipped at the antennal club. There is a scent brand within space 7 on the hindwing and appears as a prominently raised circular disc on the underside of the males of the Indigo Flash.

Text by Khew SK : Photos by David Chan, Khew SK, Horace Tan, Bene Tay and Mark Wong

Butterfly of the Month - February 2024

Butterfly of the Month - February 2024

The White Royal (Pratapa deva relata)

On this special once-every-four-years day of 29 Feb, we feature one of our "royal" butterflies from the Lycaenidae family. The Lycaenidae, often referred to as the Blues and Hairstreaks, is represented by the largest number of species in Singapore. As many of the species are cryptic and superficially very similar-looking, more species are being added to the Singapore checklist as new information becomes available, or observations of species which were previously missed are included to the list.

Our Butterfly of the Month for February 2024 is the moderately rare White Royal (Pratapa deva relata). This species was a recent re-discovery back in 2007 when it was first photographed at an urban area near Telok Blangah Hills Park. It was subsequently observed that the caterpillars of this species depends on the parasitic mistletoe, Rusty Mistletoe (Scurrula ferruginea) as its host plant. With a more targeted observation of habitats where this parasitic plant grows, it was observed that the species is often present in the vicinity of the host plant.

The White Royal is widely distributed across Singapore and found in urban parks and gardens, as well as the nature reserves and areas where the caterpillar host plant can be found. The distinctive parasitic plant can often be spotted growing on other plants where its "rusty" undersides of its leaves stand out. The adult butterflies are often spotted singly where they occur, but females have been seen in small numbers, ovipositing on its host plants.

Male (top) and Female (bottom) White Royal showing their upperwings

The upperside of the male White Royal is a deep lustrous blue with broad black borders, particularly at the apical area, on the upperside of the forewings and a series of black marginal spots on the hindwings. The females feature paler blue uppersides, also with broad black apical borders on the forewings.

A female White Royal sunbathing with open wings

A "rear view" of the White Royal showing its tornal lobe

The underside of both sexes is greyish white with a series of post-discal narrow black streaks. The underside of the hindwing has a prominent orange-crowned black marginal spot in space 2. There is a pair of white-tipped tails at the ends of veins 1b and 2. The tornal lobe on the hindwing is black and orange with white cilia on pristine individuals.

The eyes of the White Royal are transparent instead of jet black, as in the case with many of the related species. The legs are greyish-white throughout. The antennae are black-and-white banded, and orange tipped at the club.

A female White Royal resting on the leaf of the Rusty Mistletoe after ovipositing

The complete life history of the White Royal has been successfully recorded in Singapore on its single caterpillar host plant, the Rusty Mistletoe (Scurrula ferruginea). This host plant, one of only a few parasitic and hemi-parasitic plants found in Singapore, is featured in an earlier blogpost about Mistletoes and their importance to the butterfly fauna in Singapore. At least 4 species of Lycaenidae caterpillars depends on the Rusty Mistletoe for survival and continued existence in Singapore.

Text by Khew SK : Photos by Khew SK, Loh MY, Richard Ong, Horace Tan, May Yap and Yip Jen Wei

Butterfly of the Month - January 2024

Butterfly of the Month - January 2024

The Fulvous Pied Flat (Pseudocoladenia dan dhyana)

A male Fulvous Pied Flat sunbathing on top of a leaf in the late afternoon

We kick start the Butterfly of the Month series with a species from the family Hesperiidae, or commonly referred to as Skippers. Skippers tend to fly rapidly and are often mistaken for moths. They have exceptionally large eyes and fat robust bodies. The sub-family Pyrginae, or Flats and Spread-Winged Skippers, is represented by 12 species from 8 genera in Singapore. Some are very rare and are classified Data Deficient in the latest Singapore Red Data Book, due to very few or very recent sightings and there is an element of doubt as to the species' existence in Singapore.

Fulvous Pied Flat - Male (Top) and Female (Bottom)

Our Butterfly of the Month for January 2024 is the Fulvous Pied Flat (Pseudocoladenia dan dhyana) a medium-sized species that was originally not recorded from Singapore in the early authors' reference checklists. It is hence deemed as a non-native or exotic species. However, after its discovery it has regularly been observed and hence appears to be naturalised with several colonies found in Singapore.

First spotted at the Bukit Timah Nature Reserve, the species is closely associated with forested habitats where its caterpillar host plant, Cyathula prostata (Amaranthaceae) grows in abundance. The plant is not difficult to cultivate, and where it is found, can be common. It is a low growing plant, usually seen as ground cover and spreads quite fast when it grows. The species is widely distributed, with colonies found at Upper Seletar Reservoir Park and at the forested areas beside Cleantech One in Nanyang Avenue in Jurong.

Fulvous Pied Flats feeding on various flowering plants

The common name of the Fulvous Pied Flat generally describes the species. Fulvous is an adjective that describes a dull yellowish-brown or tawny colour. Pied is an adjective that describes something that has two or more different colours usually in patches or spots. And being a member of the Pyrginae sub-family, it is a Flat that describes the behaviour of the species - usually perched with its wings spread open flat.

The Fulvous Pied Flat usually makes its appearance in the cool early hours of the morning. It can also be observed in the later part of the afternoon on hot sunny days, where it is seen to sunbathe on the top surfaces of leaves.  During other times of the day, it tends to fly and perch on the undersides of leaves - a behaviour that is similar to many of the Pyrginae species.

Fulvous Pied Flat - Male (Top) Female (Bottom) - Note the forewing cell spot differences.

The upperside of the Fulvous Pied Flat is reddish brown. The two large yellow hyaline spots at the end of the forewing cell, which are conjoined to form a distinctive V-shaped spot, distinguishes the male from the female of this species. In the female the spots are much reduced and appear whitish. There are other dark brown diffused spots on the fore and hindwings.

The full life history has been successfully recorded in Singapore on the caterpillar host plant Cyathula prostata. This plant has a wide distribution and can be found in Asia, Australia, Africa and tropical America. Parts of the plant are used as food and medicines for diarrhoea, dysentery, pain-relief etc. Locally, this plant can be found in waste places, forest margins and alongside trails in the northern and western catchment reserves. All early stages of the Fulvous Pied Flat feed on the leaf lamina of the host plant and retreat to their leaf shelters between feeds. Typically, they rest in a curled-up posture within the shelter.

Text by Khew SK : Photos by Ash Foo, Khew SK, Lee Yue Teng, Richard Ong, Michael Soh, Horace Tan and Alson Teo