01 December 2019

Butterflies of South Africa

Feature Book :
Butterflies of South Africa

A friend who recently visited South Africa managed to get me a copy of the Field Guide to Butterflies of South Africa by Steve Woodhall. A prolific author of several books on butterflies, Steve has effectively introduced the amazing diversity of South African butterflies through his excellent books and on social media to those of us in "faraway" lands who can only drool at the beauty of the butterflies in Steve's backyard.

The Field Guide to the Butterflies of South Africa was first published in May 2005. It was back then, the definitive book for butterfly enthusiasts and sold over 20,000 copies around the world! Steve went on to published several other books on butterflies in 2008, 2013 and 2016 and even has an app for iphones. He is currently working on the 2nd edition of his Field Guide and it is expected to be launched some time in 2020.

A nice "index" at the start of the book that shows all the families/sub-families of the butterflies featured in the species accounts section.

Butterflies of South Africa is a 440-page softcover book in a handy standard A5 sized format. The majority of the 1,800 photos in the book are by Steve and the remaining photos are by a group of his associates. The photos are mainly of field shots of the 660 species in South Africa, with some pinned specimen shots where field shots are not available.

Biogeography, vegetation ecosystems and habitats where the butterflies are found in South Africa

The book starts with the necessary introduction to butterflies - their taxonomic classification, biology, life history. anatomy, life history and so on. As the land area of South Africa is relatively large, the author elaborated on the different biomes (vegetation ecosystems) found in South Africa.

Introduction section with anatomy, taxonomy, etc.  Here, the Comstock system of wing venation is used

The largest section in the book, as can be expected, is the species accounts. The author organised the book by families, starting with the group with the largest number of sub-families - the Nymphalidae. It is then followed by Lycaenidae, Pieridae, Papilionidae and Hesperiidae. It is interesting to note that the 6th family in the butterfly world, Riodinidae (Metalmarks) is missing from South Africa.

This blogpost features some of sample pages of the species accounts. Each pair of pages are organised such that the write-ups are on the left, and the photos of species described are on the right. This is a convenient format for readers, as the pictures correlate directly to the write-ups without having to flip and cross-reference to a set of plates located elsewhere in the book, or even having to turn to a next page to view a photo of a butterfly that was described in a preceding page.

The descriptions of the species and other useful information are formatted on the left page, with the corresponding photos of the species on the right.  Photos are labeled for easy reference and there is no need to flip pages to refer to photos in appendices or plates in other parts of the book.

Each photo is labeled 1A, 1B, 2A and so on, to correlate to the write ups, showing upperside, underside, male or female of a species as the case may be. Where field shots are unavailable, these are supplemented with photos of pinned specimens. As field butterfly photography goes, it is not always possible that one can get good photos of all the uppersides and undersides of every species. Hence the most practical way of allowing readers to have a view of the uppersides (or undersides) of some species, a shot of a pinned specimen may be the best compromise.

Danainae section featuring the genus Amauris

The Danainaes of South Africa look quite different from those of Southeast Asia and have interesting common names to boot. The genus Amauris have common names like Layman, Friar, Novice and Chief! It appears that there are only 6 Danainae species in South Africa, of which the African Monarch (Plain Tiger in Singapore) is one species that we have in common. However, in South Africa, there are no fewer than 7 different forms of this species.

There are 21 Acraea species in South Africa compared to Singapore's single non-native species

The subfamily Heliconiinae is of interest, particularly from the genus Acraea. In Singapore, the Tawny Coster (Acraea terpsicore) was added as a new species in 2006. It is the sole representative of the genus found here. However, in South Africa, there are 21 Acraea species! The diversity in colours and patterns of this genus is quite amazing. But the similarities with A. terpsicore in wing shapes and general appearance are obvious.

The amazing Emperors (Charaxes) species of South Africa

The subfamily Charaxinae features some of the most spectacular butterflies in the world.  Their intricate patterns and colours are often a sight to behold.  Often referred to as the Rajahs in Asia, the genus Charaxes usually features robust-bodied species with twin tails.  Over in South Africa, there are 23 species (of which two species have single tails).  Definitely a country to keep Charaxes enthusiasts busy!

The Pansy species.  Blue Pansy is the name given to Junonia oenone in South Africa

South Africa shares many species of Junonia with Southeast Asia. There are 6 species, of which J. orithya (Blue Pansy in Singapore) is also extant as a different subspecies. However, in South Africa, it is called the Eyed Pansy instead, whilst the common name Blue Pansy is reserved for another species, Junonia oenone oenone.

The Bar species (related to the Silverlines in Asia)

The Lycaenidae family features amongst the largest number of species worldwide. Over in South Africa, the genus Cigaritis is related to the Spindasis found in our part of the world. And indeed, the jury is out (or rather, still debating) on which should be the "right" genus name for these pretty Silverlines. They are called "Bars" in South Africa but are no less pretty than their Asian counterparts.

Amongst these amazing Lycaenidae is the Golden Flash (Chrysoritis phosphor) a sought-after rarity in afromontane forest. Read the humourous article by Paulo and Rob Candotti about how Steve managed to capture one of these beauties.

The family Pieridae features the same white and yellow species that we can find all around the world, and South Africa's diverse range of these usually fast-flying brightly coloured butterflies is no exception. Some of the genera that are similar to the Southeast Asian butterfly fauna are Appias, Leptosia, Eurema and Catopsilia.

The spectacular Swordtail species of South Africa with their long elegant tails

The Birdwings and Swallowtails are amongst the most spectacular butterflies in the world. South Africa has 14 species in only two genera - Papilio and Graphium. As a comparison, Singapore is home to 18 species of Papilionidae. However, the Swordtails of South Africa are gorgeous and also share the same mud-puddling habits of their Asian cousins.

Some colourful Skippers of South Africa

The final family, the skippers or Hesperiidae showcases some pretty amazingly coloured species in South Africa. Generally similar in appearance to their Asian cousins amongst the majority of the species, the Hesperiidae of South Africa features a good variety of brown, orange and spotted species.

Coming Soon! The 2nd Edition of Butterflies of South Africa by Steve Woodhall

With this short blogpost introducing Steve Woodhall's Butterflies of South Africa, I hope that I have whetted your appetite for South African butterflies. If you are thinking of getting a copy of the book, the advice is don't! The reason is that Steve has been working on a 2nd edition of this book and will certainly outdo himself in the forthcoming 2020 edition that will be out on the shelves in May next year (according to Amazon).

Text by Khew SK : Photos reproduced from Butterflies of South Africa, with the kind permission of Steve Woodhall.

24 November 2019

Relative Abundance Indicators

Butterflies : Relative Abundance Indicators
From Common to Rare

A Malay Lacewing feeding on the flower of Lantana camara at Central Catchment Area. Circa 2005

A friend recently asked me, "so has your butterfly survey project concluded?". My answer was yes and no. Firstly, surveys to "inventorise" our local butterfly fauna are always "ongoing". Although each official project may last 1-2 years, like the Bukit Timah Nature Reserve Comprehensive Biodiversity Survey, and the current Pulau Ubin Biodiversity Survey commissioned by the National Parks Board, many local butterfly watchers and enthusiasts continue to observe and keep records of butterfly activity in Singapore.

A Magpie Crow feeding on a sweaty backpack strap at MacRitchie Nature Trail. Circa 2005

With social media and digital photography, it is much easier to collect records and collate information on butterflies today. Apps such as Biome and iNaturalist are relatively good repositories of sightings and documentation of species diversity, abundance and location. Data collected can henceforth be analysed and may give a better overview of butterfly activity across Singapore the years.

In the Red Data Book, the convention used to describe the relative abundance of species is crafted after the International Union for Conservation of Nature (IUCN) guidelines. The Red List Categories and Criteria were basically categorised by "threat to extinction". For the layman, it may be rather scientific and hard to relate to.

Hence, when I was working on the Butterflies of Singapore, I adopted a less scientific approach  and used a more simple "Relative Abundance Indicator" table and layman-friendly 6-category abundance indicators from "Common to Very Rare". The final category of "Seasonal Migrant" covers all the occasional appearances of species that are non-resident in Singapore.

The annual variability and irregularity in the sightings of certain species over the years continue to affect their relative abundance. It is more pronounced in some species compared to others. Hence what was listed as "common" or "moderately common" may be come "rare" and conversely, what was "rare" or "moderately rare" may become "common".

Examples of some of the more obvious species that may require a re-classification of their abundance, are highlighted here. These are certainly not exhaustive nor definitive and the relative abundance indicators will continue to evolve and change over the years, as more data and observations are collected.

1. The Magpie Crow (Euploea radamanthus radamanthus)

A Magpie Crow puddling at a damp streambank near Rifle Range Trail. Circa 2008

The Magpie Crow was widely distributed across Singapore in the past decade and often spotted mainly in the nature reserves. It was most regularly seen at the Bukit Timah Visitor Centre before the upgrading works, but has been spotted at Rifle Range Road Trail, Sime Forest, MacRitchie Reservoir Park, Upper Seletar Reservoir Park and many other localities.

A trio of Magpie Crows puddling at a muddy spot at Upper Seletar Reservoir Park in 2005

A Magpie Crow puddling on a concrete water pipe

Considered "Moderately Common" between 2005 and 2015, the Magpie Crow appears to be rarely sighted in recent years. Records from recent social media posts seem to validate this observation. Have there been any ecological changes that made the species become much rarer? Has its caterpillar host plant been affected in some way and become less common? We will need to keep looking out for this species again in the coming years to see whether its population rebounds.

2. The Malay Lacewing (Cethosia hypsea hysina)

The Malay Lacewing, once a regularly-seen species in the nature trails, appears to be much rarer these days

A favourite amongst butterfly watchers and photographers, the Malay Lacewing features intricate patterns on black and orange coloured wings and is one of the prettiest butterflies in Singapore. The species was also categorised as "Moderately Common" as it was often seen flying around in the Central Catchment Nature Reserves along forest trails and feeding on flowering plants.

A Malay Lacewing perched on a leaf at Ulu Sembawang Park Connector, Mandai. Circa 2013

Again, after 2015, records of sightings of this species have decreased significantly. The non-native Leopard Lacewing, discovered in 2005, was not known to aggressively compete with the Malay Lacewing for its host plant, Adenia macrophylla, as its caterpillars prefer to feed on Passiflora foetida found abundantly in urban areas. Could something have changed and the "invader" has edged the native species out? This is something for the environmental ecologists to study further.

3. The Common Tree Nymph (Idea stolli logani)

Will the Common Tree Nymph soar amongst the treetops as commonly as before?

The large and spectacular Danainae is always a crowd pleaser whenever it appears high up in the forest canopy, soaring and gliding amongst the treetops. It is a forest-dependent species and the Common Tree Nymph has almost exclusively been sighted only within the forested nature reserves of Singapore. Also categorised as "Moderately Common" between 2005 and 2015, sightings of this species have become rarer these days.

Three Common Tree Nymphs frolicking at tree-top level at Upper Seletar Reservoir Park in 2008

In the past decade, when the Spicate Eugenia is in full bloom, the flowers attract a myriad of butterflies.  The Common Tree Nymph is one of the species that makes an appearance.  In recent years, when this tree is in flower, the Common Tree Nymph is sadly absent.

At the forest fringes of the nature reserves, when the Spicate Eugenia (Syzygium zeylanicum) trees flower, there are many species of butterflies that are instantly attracted to feed on the nectar of the flowers. The Common Tree Nymph was one of the species that turns up regularly - sometimes even up to 3-4 individuals. In the past few years, when the Spicate Eugenia trees are in bloom, the Common Tree Nymphs have failed to show up. Has anything changed in the environment to make this species become "Rare"?

4. The Common Three Ring (Ypthima pandocus corticaria)

The Common Three Ring, the largest of the Ypthima species, is no longer as common as before

This "unattractive" butterfly was described in the reference book, Butterflies of the Malay Peninsula to "almost dispute the claim of the Common Grass Yellow to be regarded as the commonest butterfly in Malaya". Usually seen along forest fringes amongst grassy patches, this species was categorised as "Common". It flies close to the ground, and in the past, several individuals can be encountered at its favourite locations.

Today, the species is not as often encountered. Could it be due to the reduction of its grass host plant, Ischaemum muticum? For a common butterfly, its life history is interestingly long - between 30-35 days as a caterpillar. Did something happen in its habitats to interrupt the life history development? Once again, should the Common Three Ring, which was previously "Common" may now have to be reclassified as "Moderately Rare"?

The abundance of various species of butterflies will continue to change and evolve, as the environment, habitats and ecology changes over the years. Climate change may have a strong influence on these factors. Nature groups and researchers with the resources to undertake projects to sustain butterfly populations in Singapore may need to widen their scope to look at some of these previously "common" species and target species recovery programmes to include these butterflies.

Text and Photos by Khew SK

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