25 July 2015

Larval Host Plant for Butterflies: The Chinese Violet

Butterflies' Larval Host Plants #2
The Chinese Violet (Asystasia gangetica micrantha)

This 2nd instalment of our Butterflies' Larval Host Plants series features the Chinese Violet (Asystasia gangetica subspecies micrantha), a member of the family Acanthaceae, which is a family of dicotyledonous flowering plants occurring as tropical herbs, shrubs or twining vines.

A. gangetica micrantha is native to sub-Saharan Africa. It has spread to and become naturalized in other tropical regions including Singapore where its occurrence is widespread as a weed in multiple habitats including wastelands, roadside, forest fringes, coastal areas and other neglected land parcels.

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
Other Local Names : Ara Songsang, 赤边樱草
Larval Host for Butterfly Species: Hypolimnas bolina jacintha (Jacintha Eggfly), Doleschallia bisaltide ?bisaltide var. (Autumn Leaf), Junonia orithya wallacei (Blue Pansy).

A small patch of the Chinese Violet on the side of a pathway at Mount Faber.

An ascending and spreading herb, the Chinese Violet is a fast growing plant that could reach up to a height of 60cm, and to about 100cm if supported. The stems root easily when the nodes come into contact with moist soil.

A young plant of the Chinese Violet establishing itself at a patch of soil (disturbed by foraging wild boars) at a reservoir park, showing the branching of stems.

The leaves are simple, opposite and decussate (successive pairs of opposite leaves occur at right angle to each other). Each leaf is ovate or heat-shaped, 3 to 7.5cm long. In parts of Africa, the leaves are used as a vegetable and as a herbal medicine.

A top view of two successive pairs of leaves, showing the opposite and decussate arrangement.

A side view of two successive pairs of leaves, showing the opposite and decussate arrangement.

Flowers of the Chinese Violet are small and tubular, each up to 3.5cm long. There are usually 6 to 10 flowers borne on one side of a spike-like inflorescence. The calyx (sepals) is deeply 5-lobed, and the five spreading petals are mostly white with the bottom petal bearing purple blotches. These bisexual flowers attract insects including various species of butterflies to act as pollinators in the reproduction process.

An inflorescence with two flowers near bottom and flower buds further up.

Close up view of a flower of the Chinese Violet.

Butterflies taking nectar from the flower of the Chinese Violet. Top left: Chestnut Bob, Top right: Cabbage White; Bottom left: Common Dartlet; Bottom Right: Common Tiger.

Butterflies taking nectar from the flower of the Chinese Violet. Top left: Fulvous Pied Flat, Top right: Telicota sp.; Bottom left: Pitcher Blue; Bottom Right: Tree Flitter.

The flower buds on an inflorescence of the Chinese Violet do not blossom simultaneously but progressively from the bottom to the top, and fruits would be forming while the upper flower buds are yet to blossom.

An inflorescence of the Chinese Violet showing the progressive development of the flower buds, in the bottom to top order.

Each fruit is a club-shaped capsule, up to 35mm long, green when developing and pale brown when ripened. Each fruit has 4 seeds which are brown, lens-shaped with irregular margins. The seeds are expelled explosively upon ripening of the fruit.

Two young fruits near bottom of an inflorescence of the Chinese Violet.

Two fruits, one ripened, at the terminal end of an inflorescence of the Chinese Violet.

Two views of an opened fruit capsule with one remaining seed shown.

In Singapore, the Chinese Violet also serves as the larval host plant for three butterfly species: Jacintha Eggfly, Autumn Leaf and  Blue Pansy. All three belong to the Nymphalidae family and the Nymphalinae sub-family.

A Jacintha Eggfly butterfly.

An Autumn Leaf butterfly.

A Blue Pansy (female) butterfly.

Eggs of these three butterfly species are laid singly or in a small, loose cluster on the underside of a leaf of the Chinese Violet.

A female Jacintha Eggfly laying eggs on the underside of a leaf of the Chinese Violet (not far from the Vivocity mall).

A female Autumn Leaf butterfly laying eggs on the underside of a leaf of the Chinese Violet.

Caterpillars of all three species feed on leaves of the Chinese Violet and typically rest on the underside of a leaf when resting.

Several caterpillars of the Autumn Leaf butterfly sighted on the Chinese Violet in a wasteland.

A final isntar caterpillar of the Autumn Leaf butterfly sighted on a Chinese Violet plant at a forest fringe.

A Blue Pansy caterpillar found on the inflorescence of a Chinese Violet plant at a roadside in Jurong.

The caterpillars of all three species would wander away from the host plant (seeking a pupation site) when it is time to pupate. However some of them could still opt to pupate on the underside of a leaf or a leaf stalk of the Chinese Violet.

A pre-pupatory larva of the Autumn leaf found on the underside of leaf of the Chinese Violet.

A pupa of the Autumn leaf found on the underside of leaf of the Chinese Violet.

Next time when you are out for a walk in our parks and forests, or simply taking a stroll on a pavement in your residential estate, do take a good look at any patch of weeds present, chances are that the Chinese Violet will be there. And you might just be rewarded with a sight of insects visiting its flowers, or caterpillars munching away or resting on its leaves.

Text by Horace Tan, and Photos by Tan Ben Jin, Mark Wong, Khew SK and Horace Tan.

18 July 2015

Butterfly of the Month - July 2015

Butterfly of the Month - July 2015
The Colonel (Pandita sinope sinope)

We have just edged past the halfway mark of the year 2015. A relatively quiet month so far, compared to the more tumultuous preceding months. The summer heat is upon us as Singapore's outdoor ambient temperatures move into the 30's - and made worse by the high humidity. On my short business trip to Delhi and Ranchi in India at the end of last month, I experienced even higher temperatures, although fortunately, the monsoon rains have just started there.

ButterflyCircle members had an enjoyable weekend at the Festival of Biodiversity 2015 at the end of June. More forthcoming community projects with NParks are on the cards, with the NParks Butterfly Count project in September. A challenging project, considering that it involves the general community and sightings of butterfly species in urban parks have to be recorded and counted. Unlike birds, sighting and identifying butterflies requires a bit more experience and training. It will be a good platform to learn how best to deal with field surveys with beginners.

On the local political front, the signs of general elections (GE) are in the air. A lot of chatter in social and mainstream media and speculation on when our PM is going to announce the date of the GE. In an era of greater awareness and a more educated electorate, Singapore is at a "first-world" level of democracy where high majorities for the ruling party are probably something that can no longer be expected. Again, food for thought, as we wait with bated breath for GE.

Across our northern border, the political arena is even more complex. Allegations of corruption of unprecedented proportions at the highest political office gripped Malaysians of all walks of life. Alleged "indisputable" evidence from a prominent western media giant pointed to large sums of money being misappropriated. Again, as the drama unfolds, this will be another significant event in the political history of Malaysia. We will have to wait and see what pans out.

Further drama was in the news in the global scene, when the Greeks voted on a referendum regarding the bailout conditions of their country's debt. On the economic scene in Asia, China's stock markets took a bashing dropping a third over the past month. It is no wonder that economic soothsayers are predicting more doom and gloom in the global economy - a situation that would no doubt affect Singapore as well.

Let's leave the worldly woes for awhile as we introduce our Butterfly of the Month for July 2015 - the Colonel (Pandita sinope sinope). This Nymphalidae is one of many species in the family that has been christened with military names. In my article on this blog some time back, I gave some possible reasons how this came to be.

A Colonel feeding on the ripened fruit of the Singapore Rhododendron (Melastoma malabathricum)

The Colonel is a mid-sized orange butterfly that may be considered moderately rare. However, it is quite local in distribution and often observed in the vicinity of its caterpillar host plants. Sporting an average wingspan of about 50mm, it is not an unusually large butterfly, and may be confused, when in flight, with several other orange-coloured butterflies.

The Colonel is a bright orange above, with the fore and hindwing bases shaded with brown streaks. The outer half of both the fore and hindwings is a prominent brown post-discal band and three dark submarginal lines. The underside is similarly marked, but lighter, with the basal wing area a greenish-grey.

The butterfly is skittish and active and flies with rapid beats of its wings and glides in a manner that is quite consistent with many related species in the sub-family Limenitidinae. Often it may be encountered at the ripened fruits of the Singapore Rhododendron (Melastoma malabathricum), on which it feeds greedily. In the early morning hours, it may be encountered gliding amongst the shrubbery and settling to sunbathe with its wings fully opened.

The full underside of the Colonel in this in-flight shot

It is a forest butterfly, and rarely observed in urban parks and gardens. At times, it takes on a territorial behaviour, returning repeatedly to a few favourite perches after flying around to explore its environment. When feeding, it also tends to move its wings often and is very alert. Any threatening movement by an observer will quickly spook it off to the treetops.

A newly-eclosed Colonel clinging on to its pupal shell

The complete life history of the Colonel can be found on this blog article. The host plant on which the species has been successfully bred in Singapore is Uncaria. It has also been bred in Malaysia on another plant - Nauclea subdita also from the Rubiaceae family.

Text by Khew SK : Photos by Sunny Chir, Chng CK, Khew SK, Huang CJ, Loke PF, Nelson Ong, Horace Tan and Mark Wong.

11 July 2015

Life History of the Common Yeoman

Life History of the Common Yeoman (Cirrochroa tyche rotundata)

Butterfly Biodata:
Genus: Cirrochroa Doubleday, 1847
Species: tyche C & R Felder, 1861
Sub-species: rotundata Butler, 1879
Wingspan of Adult Butterfly: 50-60mm
Caterpillar Local Host Plants: Hydnocarpus castanea (Achariaceae), Hydnocarpus alpina (Achariaceae).

A male Common Yeoman puddling on wet ground.

A pristine male Common Yeoman resting on the underside of a leaf.

Another puddling male Common Yeoman.

Physical Description of Adult Butterfly:
On the uppersdie, the wings are tawny orange with black distal margin, sinuate marginal and submarginal lines. The hindwing has a series of black post-discal spots. The female is duller orange with black margin at the forewing apex broader than that in the male. On the underside, the wings are paler orange in the male and dull brownish orange in the female. Both wings feature a silvery white transverse discal band.

A female Common Yeoman resting on a perch.

A female Common Yeoman showing us its upperside.

A female Common Yeoman sunbathing on a perch in between oviposition flights to the host plant nearby.

Field Observations of Butterfly Behaviour:
This newly discovered species has so far been sighted at two locations in Singapore. The adults are rapid in flight and not easy to photograph. Typically, photography opportunities arise when the males are puddling on wet ground, or when the females are taking breaks between oviposition runs.