24 September 2011

Life History of the Brown Awl

Life History of the Brown Awl (Badamia exclamationis)
(This is the 100th article in this life history series at BC Blog)



Butterfly Biodata:
Genus: Badamia Moore, 1881
Species: exclamationis Fabricius, 1775
Wingspan of Adult Butterfly: 45-55mm
Caterpillar Local Host Plants: Combretum sundaicum (Combretaceae), Terminalia calamansanai (Combretaceae).



A Brown Awl perching on a flower bud in a forest clearing.


A Brown Awl taking in the afternoon sun on a fallen branch.

Physical Description of Adult Butterfly:
Adults have elongated wings and the hindwing is caudate at vein 1b and excavate along the termen between ends of veins 1b and 2. Above, the wings are dark brown with greyish green scalings 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. Below, 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 in the dorsal area.


A partial view of the upperside of a female Brown Awl, note the prominent streaks/spots.


A view of the partially open wings of a male Brown Awl, note the inconspicuous streaks/spots.

Field Observations of Butterfly Behaviour:

This species is moderately rare in Singapore. Adults have been sighted in multiple locations across Singapore, including the Sungei Buloh Wetland Reserve, Mandai Orchid Gardens, Central Catchment Nature Reserve and also rarely in urban parks and residential areas. The fast flying adults have a habit of resting on the underside of a leaf or other plant parts when they rest among the foliage of a tree.


A Brown Awl perching on the underside of a leaf.


A Brown Awl enjoys the sun while perching on a brick in MOG.

Early Stages:
Across its vast area of distribution stretching from South Asia to East Asia, and to South-East Asia and southward to Australia, Brown Awl utilizes host plants in several families. Both recorded local host plants, Terminalia calamansanai and Combretum sundaicum, are in the Combretaceae family. It is thus very likely that more host plants, either in the same family or others, are yet to be discovered locally for the Brown Awl. Caterpillars of the Brown Awl feed on the very young to the moderately young (before hardening) leaves of the host plants.


Local host plant: Combretum sundaicum.

The eggs are laid singly on very young shoots of the host plants. Each egg is shaped like a bun with a flattened base (diameter: 0.6-0.7mm). Prominent ridges run from the pole to the base. The micropylar sits atop at the pole. Initially greyish white in coloration, the entire egg turns wine red as it develops, and then decolorizes again to yellowish red when the caterpillar is ready to emerge.


A close-up view of a young shoot of Combretum Sundaicum, showing two eggs of the Brown Awl.


Two views of a 1-day old egg of the Brown Awl.


Two views of a mature egg of the Brown Awl, note the black larval head visible through the egg shell.

It takes 2 days for the collected egg to hatch. The young caterpillar eats just enough of the shell to emerge, and has a length of about 1.5mm. It does not make an attempt to devour the egg shell after its emergence. The golden and cylindrical body has a number of very short white setae. The large head is black, slightly bi-lobed and lightly hairy. The body turns pale yellowish green as it feeds on the leaf lamina and grows in this initial instar.


Two views of a 1st instar caterpillar, early in this stage, length: 1.7mm.


Two views of a 1st instar caterpillar, length: 1.9mm.

The young caterpillar constructs its first shelter by spinning a silk web over a void of space on the young shoot. It rests within the shelter and ventures out to eat on nearby leaf surface. In later instars, the Brown Awl caterpillars also construct leaf shelters but do so by joining leaf blades together. The larval growth of the Brown Awl is rapid in pace for all instars, with all but the final instar lasting only 1.5-2.5 days.


A late first instar caterpillar in its shelter. The focus was varied to show details in the net of silk threads securing the shelter.

After reaching a length of about 3.4-3.8mm in the 1st instar, the caterpillar moults to the next instar after a short dormant period. The 2nd instar caterpillar is pale yellowish green with a faint brown rings on its body segments, from the pro-thorax to the 8th abdominal segment. The yellowish head has an upper transverse brown stripe and two lower short stripes on each side of the adfrontal area. The body and the black head capsule are covered in numerous tiny setae.


Two views of a 2nd instar caterpillar, length: 5mm.


A second instar caterpillar in its shelter.

The 2nd instar caterpillar reaches a length of about 6.5-7.5mm, and after 1.5-2 days in this stage, it moults again. The 3rd instar caterpillar has 14 dark brown to black black rings, bold and prominent against the pale yellowish green of the body ground color. There is one ring to each of the 13 body segments and one on the posterior body edge. On the yellow head, the stripes have also become darker and more prominent. This instar lasts another 1.5-2 days with the length reaching 12mm.


Two views of a 3rd instar caterpillar, length: 9.5mm.

The 4th instar caterpillar resembles the 3rd instar caterpillar mostly but has additional intra-segmental dark rings, typically 3 to each segment. These rings are much thinner in width compared to the inter-segmental rings. This penultimate instar takes about 1.5-2 days to complete with the body length reaching up to 21mm.


Two views of a 4th instar caterpillar, length: 15.5mm.

The final and 5th instar caterpillar has similar body markings as the 4th instar caterpillar. Noteworthy is that dark inter-segmental rings are particularly broader in the 2nd, 4th, 6th and 8th abdominal segments. On the head capsule, the transverse black stripes seen in the earlier instars are now broken into short and bold dash-like stripes. This stage takes about 3-4 days to complete with body length reaching up to 46mm.


Two views of a 5th instar caterpillar, early in this stage, length: 30mm.


Two views of a 5th instar caterpillar, later in this stage, length: 43mm.

Towards the end of 5th instar, the body of the caterpillar gradually shrinks in length. The fully grown caterpillar ceases feeding and stations itself in a leaf shelter. During the early part of this pre-pupal stage, the caterpillar constructs a silk girdle across the dorsum of its anterior abdominal segments, and a short transverse silk band on the substrate near its posterior end. Both the dorsal point of the girdle and the transverse band are also secured by vertical/oblique threads to the inner wall of the shelter.


Two views of a pre-pupa of the Brown Awl.

After about 1 day of the pre-pupal phase, pupation takes place within the pupation shelter. The pupa secures itself with its cremaster attached to the transverse band. The pupa has a short thorax, a rather long abdomen and a short and pointed golden brown rostrum. Fresh after the pupation event, the body is pale golden brown to dark brown, but after 0.5 to 1 day, the body surface becomes mostly covered in a white substance. Length of pupae: 24-26mm.


A Brown Awl caterpillar turning into a pupa.



Two views of a pupa of the Brown Awl at any early stage with white substance just appearing on the surface.


Two views of a pupa of the Brown Awl, after the white substance has fully formed on the surface.

After 7-8 days, the pupa becomes darkened in color signaling the imminent emergence of the adult. The next day the adult butterfly emerges from the mature pupa.


Two views of a mature pupa of the Brown Awl


A newly eclosed male Brown Awl.

References:

  • [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, The Malayan Nature Society.
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 1st Edition, 2006
  • A Photographic Monograph on Hong Kong Butterflies, Vol. 4, Hong Kong Lepidopterists Society, 2011.
Text by Horace Tan, Photos by Sunny Chir, Khew SK, and Horace Tan

17 September 2011

Butterfly of the Month - September 2011

Butterfly of the Month - September 2011
The Peacock Royal (Tajuria cippus maxentius)



















September is the 9th month of the Julian and Gregorian calendars, and one of only four months of the year that has 30 days - the others being April, June and November.  In the northern hemisphere, September heralds the season Autumn - a time of falling leaves and rich reds, oranges and browns in the landscape.  The weather cools as Mother Nature prepares for the colder weather ahead. 



















On the Singapore front, in the aftermath of the Presidential Elections where the top two candidates were separated by a whisker of a margin of 0.35%!  Singapore's 7th President, Dr Tony Tan was sworn in on 1 Sep 2011. 



















Elsewhere in the world, America remembers 9 Sep (the infamous '911'), ten years after the Al-Qaeda terrorist attacks on the Twin Towers of the World Trade Centre in New York City in which thousands lost their lives. 



















The birthstone for September is the sapphire [Greek: σάπφειρος; sappheiros, "blue stone"] which is a gemstone of the mineral corundrum, an Aluminium oxide.  The most well known colour of this gemstone is blue, and sapphire is usually synonymous with blue or purple in the nature world. 





















A maiden born when September leaves
Are rustling in September's breeze,
A sapphire on her brow should bind
`Twill cure diseases of the mind.
- Gregorian Birthstone Poems



















The butterfly of the month for September is the Peacock Royal, a pretty four-tailed Lycaenid of which the upperside of the males of the species is a brilliant sapphire blue.  The Peacock Royal frequents urban parks and gardens but can also be found in the nature reserves.  It is a fast flying butterfly, but can often be observed close up when it stops to feed at flowering plants. 



















Both males and females are encountered at flowers, although females are usually more often observed, particularly when its caterpillar host plant, the parasitic Dendrophthoe pentandra can be found growing on other trees. 



















The upperside of the male Peacock Royal is a deep sapphire blue with broad black apical border on the forewing.  The female is a light pale blue with a series of black post-discal striae on the upperside of the hindwing.



















The underside is grayish white with post-discal striae and a series of diffuse black spots. The large black tornal spots are broadly orange-crowned.  The hindwing feature a pair of white-tipped tails at veins 1a and 2.



















The adult butterflies love the red flowers of Ixora javanica and where there are healthy bushes of this plant at parks and gardens, where an observer may be able to find the Peacock Royal feeding.  



















The species is considered moderately common, as it has been seen in parks in urban Singapore and is quite widespread in distribution.  But the Peacock Royal cannot be said to be abundant.  More often than not, only individuals are sighted.  



















At certain times of the day, both the males and females have been observed to open their wings to sunbathe, displaying their more colourful upperside. 



















Most times of the day, however, they stop with their wings folded upright, especially when resting on their favourite perches.  When disturbed, they take off rapidly, moving very quickly out of harm's way.



















The Peacock Royal is one of three species of the genus Tajuria found in Singapore.  The other two, T. mantra and T. dominus are much rarer and not as often seen.  All appear superficially similar on the underside.



















Text by Khew SK ; Photos by Sunny Chir, Federick Ho, Khew SK, Simon Sng, Tan BJ, Anthony Wong & Liyana Zolpakar

This blog article is dedicated to Federick Ho, a veteran butterfly watcher and photographer, and a long-time friend and active supporter of ButterflyCircle. Federick's avatar and nick in the ButterflyCircle community is the Peacock Royal.

10 September 2011

Life History of the Common Tit

Life History of the Common Tit (Hypolycaena erylus teatus)



Butterfly Biodata:
Genus: Hypolycaena C & R Felder, 1862
Species: erylus Godart, 1824
Subspecies: teatus Fruhstorfer, 1912
Wingspan of Adult Butterfly: 27-32mm
Caterpillar Local Host Plants:
Clerodendrum inerme (Lamiaceae, common name: Wild Jasmine, Sorcerers Bush), Saraca thaipingensis (Fabaceae, common name: Yellow Saraca); Hibiscus tiliaceus (Malvaceae, common name: Sea Hibiscus); Ixora javanica (Rubiaceae); Guioa pleuropteris (Sapindaceae), Pithecellobium duice (Fabaceae, common name: Madras Thorn).


A male Common Tit, note the forewings which are more pointed.


A male Common Tit sunbathing on a leaf perch, showing off its upperside.

Physical Description of Adult Butterfly:
Above, the male is deep purple with a circular black brand on the forewing centering roughly at cell-end; the female is dull brown with a dark brown post-discal line on both fore- and hindwings, and has two large, marginal, black, white-crowned spots at spaces 1b and 2. Underneath, both sexes are pale grey, darker in the male than in the female, and have a cell-end bar and a narrow orange post-discal line on both fore- and hindwings. The forewing termen is shaded in orange and this orange shading is more extensive and extend up to the post-discal area. The hindwing has a prominent,  orange-crowned tornal black in space 2 and a smaller one on the lobe. There are two white-tipped tails at ends of veins 1b and 2, with the longer one at vein 1b. The upperside of the abdomen is colored as per wing upperside, but the underside is mostly white and black banded. The legs are also white and black-banded.



A female Common Tit sunbathing on a leaf perch.


A female Common Tit .

Field Observations of Butterfly Behaviour:
This species is not uncommon in Singapore and can be found in multiple habitats, ranging from the mangrove habitats in Sungei Buloh Wetland Reserve, Pasir Ris Park to Central Catchment Reserve, the Southern Ridges, and various urban gardens. Adults have been observed to visit flowers, puddling on roadside seepage and sunbathing with open-wings.



Another Common Tit perching on a leaf.


Another male Common Tit.

Early Stages:
The Common Tit is polyphagous as its early stages feed on a number of host plants from different families.
At Sungei Buloh Wetland Reserve, caterpillars of Common Tit have been found on leaves of Sea Hibiscus and Cleorodendrum inerme which are both common there. In the wild, the caterpillars are typically found in the company of the 'Weaver Ant' or Kerengga (Oecophylla smaragdina). Young to middle-aged leaves of various hosts are utilized by the caterpillars.


Local host plant #1: Cleorodendrum inerme.

Local host plant #2: Yellow Saraca. The caterpillars feed on the young leaves shown in the right panel.


Local host plant #3: Sea Hibiscus.


Local host plant #4: Guioa pleuropteris.

The eggs are laid singly on leaves, stems or young shoots of the host plants. Each egg is about 0.8mm in diameter, white in color with a greenish tinge when freshly laid. It is dome-shaped with a depressed micropylar at the pole, sporting a reticulated pattern of intersecting ridges with large indentations on the surface.


Two views of an egg of the Common Tit

Left: a mature egg with the young making its first nibbles at the shell.
Right: empty egg shell.


It takes about 3 days for the egg to hatch. The pale yellowish brown newly hatched has a length of about 1.4mm and has an obscure dark lateral band on each side of the body. It has a woodlouse appearance with a large pro-thoracic shield in the same coloration as the body ground colour.
The body also features rather long, black, dorso-lateral and whitish, lateral setae (hair). The head is yellowish brown. The newly hatched shows no interest in devouring the remnant of the egg shell after its emergence, and moves straight away to nibble on the leaf lamina in its vicinity. As it grows, the body color becomes more yellowish and the dorso-lateral bands become reddish brown. These bands appear to join at the posterior and anterior end. A thin, reddish, dorsal line also appears at this stage.


1st instar caterpillar, newly hatched, length: 1.5mm

1st instar caterpillars. Top: length: 2mm; Bottom: 2.5mm, in dormant mode prior to its moult.

After about 2 days of growth in the first instar, and reaching a length of about 2.6-2.7mm, the caterpillar moults to the next instar. Unlike many other butterfly species, the newly moulted does not eat the exuvia. The 2nd instar caterpillar has short fine lateral setae and numerous very short and fine hairs all over the body surface. It is mostly yellowish green with the same reddish lateral and dorsal bands seen in the L1 stage. Even at this early stage, the dorsal nectary organ is discernible on the dorsum of the 7th abdominal segment.



Two views of a 2nd instar caterpillar, early in this stage, length: 2.4mm..

Two views of a 2nd instar caterpillar, length: 3.3mm.

Two early instar caterpillars of the Common Tit attended by Weaver Ants on the back of leaf of the Sea Hibiscus.

The 2nd instar caterpillar reaches a length of about 4.5-4.7mm, and after about 2 days in this stage, it moults again. The yellowish green 3rd instar caterpillar has a more striking appearance with the dorso-lateral red bands now outlined in white and there is now a reddish brown, white-crowned anal patch, extending from the dorsal nectary organ to the anterior end. The peripheral edge of the body becomes more prominently whitish as growth progresses in this isntar. The 3rd instar takes about 2 days to complete with the body length reaching about 8.7mm.


Two views of a 3rd instar caterpillar, early in this stage, length: 4.3mm


Two views of a 3rd instar caterpillar, late in this stage, length: 8.3mm.

The 4th instar resembles the late 3rd instar caterpillar closely with the body ground color in pale to lime green. The broad dorsal band, flanked by the dorso-lateral white-red bands, is edged with reddish brown strips, and has a thin, central intermittent red line. In some specimens, the reddish dorso-lateral band becomes less well defined by infusing white patches. The 4th instar takes about 2 days to complete with the body length reaching 13.5-14mm.



Top: Late 3rd instar caterpillar, dormant prior to its moult.
Bottom: A newly moulted 4th instar caterpillar.



Two views of a 4th instar caterpillar, late in this stage, length: 14mm


Another newly moulted 4th instar caterpillar next to its exuvia.

The 5th instar caterpillar has similar but more striking markings especially in the reddish brown to orangy brown dorso-lateral bands. These bands, unlike in the earlier instars, do not extend into the prothoracic segment. In some specimens, there are noticeably much greater infusion of white in the dorso-lateral bands.


Two views of a 5th instar caterpillar, late in this stage, length:: 21mm


Two views of anoter 5th instar caterpillar, late in this stage, length:: 21mm. Note the greater extent of change to white in the dorso-lateral bands.

After about 4 days of feeding and reaching a length of about 22mm, the caterpillar actually stops food intake for about 1 day. During this time, its body gradually shortened and decolorised to shades of green. At the end of this period, typically the caterpillar chooses a spot on the leaf underside as its pupation site.


Weaver ants attending to a 5th instar caterpillar on a leaf of Cleorodendrum inerme.

The pre-pupa caterpillar prepares for pupation by spinning a silk girdle and a silk pad to which it attaches itself via its anal claspers. After 1 day as a pre-pupa, pupation takes place. The pupa is predominantly pale green and has numerous small dark green speckles. Pupal length: 13-14.5mm. The pupa has a typical but stout Lycaenid shape.


Two views of a pre-pupa of the Common Tit lying (immobile).


Two views of a pupa of the Common Tit. >

Even at the pupal stage, at least for the initial few days of this stage, a little slit on the dorsum of the 7th abdominal segment has been found to exude fluid droplets. This is likely the remnant or continuation of the dorsal nectary organ of the larval stage.


Close-up views of the posterior end of a pupa, showing the remnant (inset) of the dorsal nectary organ still exuding fluid.

Five days later, the pupa turns rather dark, first in the wing pad and thorax, then progressively in the abdomen. The extent of the blue patches in the wing pads gives an early indication of the gender of the soon-to-emerge adult. The next day, the pupal stage comes to an end with the emergence of the adult butterfly.


Two views of a mature pupa of the Common Tit.


A newly eclosed Common Tit, still in the midst of wing expansion.


A newly eclosed female Common Tit.

References:

  • [C&P4] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, The Malayan Nature Society.
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 1st Edition, 2006

Text by Horace Tan, Photos by James Chia, Sunny Chir and Horace Tan