Life History of the Linna Palm Dart

Life History of the Linna Palm Dart (Telicota linna )

Butterfly Biodata:
Genus: Telicota Moore, 1881
Species: linna Evans, 1949
Wingspan of Adult Butterfly: 32-35mm
Caterpillar Local Host Plants: Bambusa multiplex (Poaceae; common name: Hedge Bamboo, Chinese Dwarf Bamboo).

A female Linna Palm Dart, wing upperside view.

A female Linna Palm Dart, wing underside view.

Physical Description of Adult Butterfly:

On the upperside, the wings are black with an orange post-discal band on the forewing running from the dorsum and bent over at vein 6 to continue along the costal margin. The orange-yellow post-discal band on the hindwing runs from vein 1b to space 6. The male has a grey brand on the forewing from about the middle of vein 1b to vein 4. The brand is usually straight and not placed closer to the forewing cell or the inner margin of the post-discal band. Base of space 2 in the forewing of the male is black or largely so. The female has the forewing generally darker, with much of the basal organge darkened. On the underside, the wings are ochreous with post-discal bands outlined with black. The veins crossing the orange-yellow band on the hindwing are not dark-dusted.

A male Linna Palm Dart, wing underside view.

A male Linna Palm Dart, wing upperside view.

Field Observations of Butterfly Behaviour:

A recent addition to the Singapore Checklist, the Linna Palm Dart is moderately rare in Singapore. The adults are strong flyers and are typically sighted along the forest edge and grassy undergrowth. The swift flying adults have been observed to visit flowers and sunbath with open wings in sunny weather.

A Linna Palm Dart visiting flowers for its sugary intake.

A male Linna Palm Dart.



Early Stages:

In Singapore, Linna Palm Dart has thus far been bred on one bamboo species, Bambusa multiplex. The caterpillars feed on leaves of the host plant in all instars and live in leaf shelters. As the caterpillar grows in size through progressing instars, it migrates to ever larger shelters constructed by joining cut leaf fragments or the opposite edges of a single blade.

Local host plant: Bambusa multiplex.

The eggs are laid singly on a leaf blade of the host plant, typically on the underside. Each dome-shaped egg is creamy white and appears to be smooth to the naked eyes. A closer inspection reveals numerous short, discontinuous and irregular tiny ridges running in a longitudinal direction. Each egg has a basal diameter of about 1.1mm.

An egg of the Linna Palm Dart laid on the underside of a leaf blade of Bambusa multiplex.

Two views of an egg of the Linna Palm Dart, diameter: 1.1mm.

It takes about 4-5 days for the egg to hatch. The young caterpillar eats just enough of the shell to emerge, and then immediately proceeds to finish the remaining egg shell. The newly hatched has a length of about 2.5-2.75mm. Its pale whitish body is cylindrical in shape with a small number of very short and tiny dorso-lateral setae. There is a tuff of relatively long setae on the posterior segment. It has a black head and a black collar on the prothorax.

Two views of a mature egg of the Linna Palm Dart.

A newly hatched caterpillar of the Linna Palm Dart in its first leaf shelter.

After consuming the egg shell, the newly hatched caterpillar constructs its first leaf shelter,  typically at the tip of a leaf blade. The body takes on a green undertone after a few feeding sessions on the leaf. The 1st instar takes about 3-4 days to complete with body length reaching 5.5mm.

Two views of a 1st instar caterpillar, length: 4mm.

The body of the 2nd instar caterpillar resembles that of the first instar, but with the dark collar on the prothorax now vaguely present. The setae at the posterior end are now proportionately shorter and the anal plate takes on a greyish coloration. The body colour is yellowish green with a dark green undertone. This instar lasts about 4 days with the body length reaching up to 7.5-8mm.

Two views of a 2nd instar caterpillar, length: 8mm.

The 3nd instar caterpillar resembles the 2nd instar caterpillar except for a more yellowish green body colour and the nearly indistinguishable collar mark on the prothorax. Unlike some of the other Telicota, the anal plate remains colored as per the rest of the body surface. The head capsule is either black or brown. This instar lasts a total of 4-5 days with the body length reaching 12mm.

Two views of a 3rd instar caterpillar with a black head, length: 7mm.

Two views of a 3rd instar caterpillar a with brown head, length: 8.5mm.

The 4th instar caterpillar resembles the 3rd instar caterpillar closely. In specimens with a brown head capsule, the base coloration is now lighter brown and there is a dark brown band right in the middle. This instar lasts 5-6 days with the body length reaching about 17-18mm.

Two views of a 4th instar caterpillar with black head, length:10mm.

Two views of a 4th instar caterpillar with brown head, length: 11.5mm.

The 5th instar does not bring about any noteworthy change in the body or head markings. This instar lasts 7-8 days with the body length reaching about 24-25mm.

Two views of a 5th instar caterpillar with black head, length:19mm.

Two views of a 5th instar caterpillar with brown head, length: 24.5mm.

In the 6th (final) instar, specimens with brown head now has its base coloration in pale yellowish brown and a dark brown band lining the epicranial suture. For those specimens with black head, small pale brown patches might appear laterally. The body is now predominantly yellow with a a green undertone.

Two views of a female 6th instar caterpillar with black head, length: 29mm.

Two views of a male 6th instar caterpillar with brown head, length: 29mm.

The 6th instar takes about 10-11 days to complete with the body length reaching up to 33-34mm, In the last day of this instar, the body gradually shorten and changes colour to pale beige brown (initially with a purplish tone). The caterpillar ceases feeding and whitish powdery substance begin to appear on its body. Next it proceeds to seal the shelter it is in with silk threads. Soon the caterpillar becomes dormant in this pupation shelter. This prepupatory phase lasts for about 1-1.5 day.

Top: a late 6th instar caterpillar wandering; Bottom: a late 6ht instar caterpillar its its pupation shelter.

A pupation shelter opened to reveal  a pre-pupa of The Linna Palm Dart.

Pupation takes place within the leaf shelter. The pupa does not have a cremastral attachment nor a silk girdle and it is mainly secured with tightly woven silk threads in the shelter. It has a short thorax and a rather long abdomen. The body is generally orangy brown, darker in the thorax and wing pad areas. Length of pupae: 19.5-20.5mm.

Two views of a pupa of the Linna Palm Dart.

After 8-9 days, the pupa becomes dark brown with the thorax and wing pads mostly black. The orange markings present on the forewing upperside are now visible through the now translucent pupal skin. Eclosion takes place the next day.

Two views of a mature pupa of the Linna Palm Dart.

A newly eclosed female Linna Palm Dart.

References:

• [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society, 1992.
• Butterflies of Thailand, Pisuth Ek-Amnuay, 2nd Edition, 2012.
• A Field Guide to the Butterflies of Singapore, Khew S.K., Ink On Paper Communications, 2nd Edition, 2015.

Text by Horace Tan, Photos by Frederick Ho and Horace Tan.

Butterfly of the Month - May 2016

Butterfly of the Month - May 2016
The Blue Glassy Tiger (Ideopsis vulgaris macrina)

The scorching temperatures from last month carried forward into May, with only a little reprieve when there were occasional rainy afternoons which cooled us down somewhat. The 36.7ºC temperature recorded last month was the 2nd highest temperature ever recorded in Singapore! Many days in May continued to see 33-35ºC temperatures, which, when outdoors, felt more like in the 40's! The NEA reported that the El Nino effect is likely to weaken by mid year, with changes in weather patterns caused by the La Nina effect taking over.



In the meantime, butterflying in Singapore can be a rather hot affair as the unforgiving weather takes its toll on both the butterflies and butterfly-watchers. The drying out of vegetation in many areas appeared to have an impact on butterfly population, particularly in the nature reserves. Whilst some species are subject to seasonality in their appearance in Singapore, there is a general drop in count and diversity of the forest-dependent species.




There is probably a strong correlation between new growth of plants (brought about by wetter weather) and the number of butterflies in the environment. Given that the weather has been hot and relatively dry in the first 4 months of the year, this may be one of the reasons for the lower butterfly counts in general. Urban species appear to be less susceptible and populations are generally stable.



Singaporeans wait for the dreaded annual haze, usually coinciding with the dry weather and slash-and-burn season in neighbouring countries. Thus far, it appears to be under control, but for how long, no one can tell. At least there are now satellite images that would give a forewarning of forest fires burning out of control. But that is all that it can do - warn of the imminent deterioration in air quality.



The general global economy is not particularly cheering anyone up either. Political battles in the form of a bye-election in Singapore and the Sarawak state elections in Malaysia resulted in definitive victories for the governments of the day with both the PAP and Barisan National winning their respective positions convincingly. Perhaps the voters chose to stand on the side of political stability of the governments in both countries in the face of the uncertain global economy.



Over on the western front, our American friends are also in the thick of their own forthcoming elections by year end, as the Republican and Democrat candidates slug it out in the primaries. It would be interesting to see what happens at the end of the year, when the new President steps into the Oval Office. What would be critical to the rest of the world, would be the foreign policy in the hands of the incoming 45th President of the USA.



Our Butterfly of the Month for May 2016 is the common Blue Glassy Tiger (Ideopsis vulgaris macrina). This medium-sized butterfly with an average wingspan of about 75mm, is widespread and appears in urban parks and gardens, mangrove environments as well as in the nature reserves.




Blue  Glassy Tiger feeding on a variety of flowering plants

It is most common in habitats where its lactiferous host plants, Tylophora flexuosa syn. tenuissima, Gymnema sp. and probably other similar vines of the Apocynaceae family grow wild. These host plants are most evident in mangrove and wetland environments and this is where the butterfly, and its closely related cousin, the Dark Glassy Tiger (Parantica agleoides agleoides), which shares the host plants, can be found in numbers.



The Blue Glassy Tiger has wings that are bluish-grey, streaked with black stripes. The ground colour of the wings appear bluer in flight when compared to the Dark Glassy Tiger, which appears greyish. The black transverse bar in the forewing cell distinguishes it from the Dark Glassy Tiger. In recent years, another species - the Grey Glassy Tiger (Ideopsis juventa sitah) has been spotted in Singapore, and it is likely to be a migrant species for the time being. In this latter species, the cell areas of both wings are lightly marked, and it appears much paler in flight than either of the extant species.



Blue Glassy Tiger on the dried seed pods of the Indian Heliotrope (top) and fresh flowers of the same plant (bottom)

The Blue Glassy Tiger flies in an unhurried manner with a slow flying characteristic. It is often seen feeding on flowers of many plants, but is particularly partial to the dried plants of the Indian Heliotrope (Heliotropium indicum), which also attracts other Danainae butterflies. Males of the species feature a distinct brand (usually of a darker colour than the surrounding area) at the sub-tornal area of the hindwing.



Blue Glassy Tigers feeding on False Dill flowers

Besides the Indian Heliotrope, another plant, the False Dill (Artemisia scoparia) also attracts various species of Danainae. The butterflies are attracted to the flowers of the False Dill and dried or damaged parts of the plant. There appears to be some form of alkaloids that the Danainaes go for. The Rattleweed (Crotalaria mucronata) also attracts the Danainaes and the Blue Glassy Tiger is no exception. It can often be seen feeding on sap from the stem, leaves and seed pods of the plant.



Blue Glassy Tigers resting in the shady understory

After feeding, a unique behaviour of the Blue Glassy Tiger is that it will look for heavily shaded areas to rest, clinging on to vines and thin branches under shade, keeping very still unless disturbed. The Blue Glassy Tiger has been successfully bred on the lactiferous vine, Tylophora flexuosa (syn. tenuissima). The spotted caterpillar sports red based tubercles and is quite attractive.



Text by Khew SK : Photos by Chng CK, Goh EC, Khew SK, Loke PF, Jonathan Soong, Horace Tan and Tea Yi Kai

Butterfly Photography at Our Local Parks - Gardens by the Bay

Butterfly Photography at Our Local Parks
Featuring : Butterfly Sanctuary @ GB


An overview of the Butterfly Sanctuary @ GB with the Marina Bay Sands Hotel in the background

Singapore's premier waterfront gardens, Gardens by the Bay, have attracted well over 24 million visitors since it opened its doors in 2012. Its visitorship numbers have exceeded similar garden attractions in the developed world by quite a bit, hovering around 6 - 8 million visitors per annum. A visit to Bay South Gardens would never be complete without taking in the awesome exhibits at the Flower Dome, Cloud Forest and the Supertrees!

Different views of the Butterfly Sanctuary @ GB

ButterflyCircle conducted a series of surveys at Bay South gardens some time back in 2013, and recorded nearly 50 species of butterflies around the gardens. All the butterflies were spotted outside the glass conservatories, of course, although there are often people who asked if there were butterflies inside the Flower Dome or Cloud Forest. One of the conservation visions of GB was to enhance the local biodiversity and to attract more species of fauna back into the site after the development was completed.

Birds galore at Gardens by the Bay

Indeed, the number of birds, butterflies, dragonflies and other mammals increased manifold after the Gardens were completed and opened to the public. A family of otters was also regularly seen frolicking around the gardens, particularly areas which are adjacent to the Marina Reservoir. Despite the human crowd, it is interesting to observe that urban biodiversity continues to return to GB. Bird watchers and photographers are seen toting their "heavy guns" around the lush greenery at GB. The Common Kingfisher (which is ironically, quite rare), is often seen at GB.

And so I've often been asked, where can you find butterflies at GB? Butterflies are free-ranging in our open environment. They are generally thermally-sensitive creatures and have been observed to shun heat sinks like buildings and metal facades that radiate heat. You will more likely see butterflies in open gardens areas where there are nectaring plants.

Location Map of the Butterfly Sanctuary @ GB

A small area near the Meadows was set aside as a "butterfly sanctuary". Though not officially known as a butterfly garden, nor are there signs to indicate that it is, this small area of roughly 600-800sqm was planted with numerous butterfly-attracting plants. Both host and nectaring plants were judiciously placed in planting beds, with a wide path allowing visitors to walk up close to the plants to admire the pretty flowers and observe the butterflies feeding on the flowers.

A Plain Tiger caterpillar on Crown Flower Plant

Amongst the caterpillar host plants available are Blood Flower (Asclepias currasavica), Crown Flower (Calotropis gigantea), Seven Golden Candlesticks (Senna alata). Rattleweed (Crotalaria retusa) and many others. Colourful flowering plants dot the entire area with Lantana, Ixora, Cosmos, Marigold, Asystasia, Snakeweed and many others, making this quiet sanctuary a nicely-designed landscaped garden.

On a typical day, an observer can spot at least 10-15 butterfly species flying around. The most obvious species (and plentiful), is the Plain Tiger (Danaus chrysippus chrysippus), flying leisurely around the flowers and often seen feeding on the red-and-yellow flowers of the Blood Flower plants. The fast-flying Lemon, Orange and Mottled Emigrants are usually around too, but are quite challenging to photograph, as they are skittish and tend to fly around non-stop.

The sun-loving butterflies like the Blue and Peacock Pansys can be regularly seen, dog-fighting amongst the shrubbery. The smaller Lycaenids like the Cycad Blue, Pea Blue and Gram Blue are sometimes seen flying skittishly amongst the flowers. Do remember to look out for the small blues like the Lesser Grass Blue, Pale Grass Blue and the Pygmy Grass Blue amongst the wild flowers growing at the turfed areas.

All the "Tigers" shot at Gardens by the Bay!

Amongst the other Danainaes, the various "tigers" are often seen - Blue Glassy Tiger, Dark Glassy Tiger, Common Tiger and Black Veined Tiger. There are also a number of Skippers zipping around in the early morning hours. The Yellow Palm Dart (Cephrenes trichopepla) is often observed and do keep a good lookout for this species basking in the sun.

Look out for the little butterflies at the Ixora bushes!

Over at the Meadows driveway and carpark, you can find the Javanese Ixora (Ixora javanica), Red Tree Shrub (Leea rubra), Bandicoot Berry (Leea indica) lining the planter beds. This area is pretty good for the shade-loving Hairstreaks like the Peacock Royal, Common Tit and Ciliate Blue. A quick walk around these flowering shrubs may sometimes pay good dividends as far as spotting these pretty Hairstreaks are concerned.

So, if you want some quiet time with the butterflies, do pop over to this little sanctuary at the Meadows. Unless there are big events planned at the Meadows, the butterfly sanctuary is usually quiet and serene. On most of my visits in recent months, I've had the whole place to myself for the entire morning! For those who drive, the car parks are always empty in the daytime and on weekends. The little garden is also close enough to public transportation networks and is a short walk away if you come by bus or MRT.

Butterfly Sanctuary @ GB is a convenient place for a butterfly "quick fix". It is also an ideal and safe place for beginners who are starting out to photograph butterflies, and near enough to amenities like a water cooler, public toilets and so on, if jungle-bashing is not yet your cup of tea. And there should be enough butterflies to keep you busy for an hour or two on each visit.

Text by Khew SK : Photos by Sunny Chir, Chng CK, Khew SK, Loke PF, Nelson Ong and Anthony Wong.

* All the butterfly shots on this blogpost were taken at the Butterfly Sanctuary @ Gardens by the Bay