Life History of the Common Bluebottle (Graphium sarpedon luctatius)
Butterfly Biodata:
Genus: Graphium Scopoli, 1777
Species: sarpedon Linnaeus, 1758
Subspecies: luctatius Fruhstorfer , 1907
Wingspan of Adult Butterfly: 90mm
Local Caterpillar Host Plants: Cinnamomum iners (Lauraceae) and one plant (to be identified) found in nature reserves.
Physical Description of Adult Butterfly:
The Common Bluebottle has a macular band which runs from the apex of the forewing to the inner margin of the hindwing on both the upper and underside. This band varies from pale green through various hues of bluish-green to deep blue. The hindwing has a series of blue submarginal spots on the upperside, and additional red spotting on the underside of the hindwing. There is a red spot near the base of the hindwing on the underside as well.
A Common Bluebottle puddling in the nature reserves
Group puddling of Common Bluebottle adults
Another puddling Common Bluebottle in an open-wing pose
Field Observations of Butterfly Behaviour:
The adults fly with a fast, agile flight typically at tree-top level. The males of this species can often be found feeding on roadside seepages or urine-tainted sand. Occasionally, a large puddling group can be found congregated on one spot. This swift-flying butterfly is common both in the nature reserves and urban parks. In flight, one normally catches a glimpse of its blue wings. Females are rarer, but often encountered when she tries to oviposit in areas where the host plants grow in abundance.
Early Stages:
The early stages of the Common Bluebottle feed on leaves of serveral plants in the Lauraceae family. There are two recorded local host plants, Cinnamomum iners (Common name: Clover Cinnamon, Wild Cinnamon) and another yet-to-be-identified plant in the nature reserves. Eggs and early stages of the Common Bluebottle are typically found on saplings at low heights.
Host plant : Cinnamomum iners
Host plant found in the nature reserves
A mating pair of the Common Bluebottle
A female Common Bluebottle was spotted laying an egg was on a sapling of wild cinnamon.
Can you spot the egg?
The eggs of the Common Bluebottle are laid on very young leaves or petioles of a sapling of the host plant. The spherical egg is creamy white with a diameter of about 1.2mm.
Left: egg laid on a young shoot.
Right: close-up on the egg shown in the left panel
Two close-up views of a mature egg of the Common Bluebottle.
Can you spot the mandible?
The egg takes 3 days to hatch, and the newly hatched has a body length of about 3mm. Immediately after emergence, it turns around and eats the entire egg shell as its first meal. Its body is initially pale yellowish brown but turning dark greenish brown hours later. It has a pair of lateral spines each of the three thoracic segments, and another white pair at the anal segment. The body also features rows of short dorsal-lateral tubercles with long setae. Between feeds, the Common Bluebottle caterpillar of all instars rests on the upper leaf surface, usually alongside the midrib.
Two views of a newly hatched Common Bluebottle caterpillar.
Almost done with the egg shell in top view. Length: 3mm
Two views of 1st instar caterpillar, 1-day old, length: 4mm
After two days of feeding on young and tender leaves, the 1st instar caterpillar grows to a length of about 5mm. Now the body looks pumped up, and assumes a yellowish brown coloration with a green undertone. After a period of inactivity, the caterpillar moults to the next instar.
1st instar caterpillar, late in this stage, length: 5mm.
In the 2nd instar caterpillar, the thoracic segments are much enlarged from the 2nd to 3rd segment, compared to abdominal segments which taper towards the anal spine. The basal ends of the thoracic spines turn black while the distal ends are still yellowish brown. The body color is dark yellowish green with the abdominal segments in alternating shades of yellow to dark green. The growth is again rather rapid, after just 2 days and the body length reaches about 6-8mm, the caterpillar moults to the next instar.
Two Common Bluebottle caterpillars (1st and 2nd instar) sighted resting on the upper surface
of Wild Cinnamon leaves in the Southern Ridges.
2nd instar caterpillar, length: 7mm
There is no drastic change in appearance in the 3rd instar caterpillar. Noteworthy are the change to completely black (with bluish shines) thoracic spines, and greater contrast between the yellow and dark green ``rings'' on the abdominal segments. This instar takes another 2 days to complete with body grown to about 10-12mm in length.
3rd instar caterpillar, length: 9.5mm
The body of the 4th instar caterpillar is mainly yellowish green, speckled with small yellow markings. Dorsally, a prominent yellow transverse band connects the two spines on the 3rd thoracic segment. A faint and thin yellow band runs laterally on each side. In contrast to yellowish green in the precedingr segments, the anal segment is bluish green. This instar lasts a further 2 days with body length reaching about 19-20mm.
Two views of a 4th instar caterpillar, length: 27mm
A 4th instar Common Bluebottle caterpillar found in the Southern Ridges
The 5th instar caterpillar closely resembles the 4th instar. The only noticeable change is the more prominent yellow transverse band connecting the 3rd pair of thoracic spines, and the basal ends of the first two pair of thoracic spines and the anal pair turning white. The 3rd pair of thoracic spine is almost completely white with the basal end circled in alternating black and yellow.
5th instar caterpillar, early in this stage, length: 29mm
As with the Common Mime featured in an earlier life history article, the Common Bluebottle caterpillars also possess an osmeterium in the prothoracic segment. This informative Australian site shows the fully everted osmeterium of the final instar caterpillar.
The 5th instar lasts for 4 days, and the body length reaches up to 40-43mm. Toward the end of this instar, the body gradually shortens in length, the body color turning almost entirely green after the fading away of the yellow transverse band and most yellow speckles. Eventually the caterpillar comes to rest on the surface of a leaf in an upright position and becomes a pre-pupatory larva.
Two views of a pre-pupatory larva of the Common Bluebottle.
Pupation takes place a day later. The pupa suspends itself with a silk girdle from the leaf surface, further secured with and a firm anchor at the posterior end. The pupa is green with a slender and obtusely pointed thoracic process. Lateral and yellow ridges run from the cremaster to the tip of pointed thoracic process giving the pupa a veined leaf appearance.
Two views of a late pre-pupatory larva of the Common Bluebottle,
with the pupation just minutes away.
A time-lapse pupation sequence of a Common Bluebottle
Two views of a leaf like pupa of the Common Bluebottle.
The pupal period lasts for 10 days, and the pupa turns black in the wing pads the night before eclosion. The bluish-green spots on the forewings also become visible through the pupal skin at this stage. The adult butterfly emerges the next morning to commence the ``high-flying'' phase of its life cycle.
Maure pupa of a Common Bluebottle caterpilar, with the left picture taken hours earlier than the right.
The orange band on the adult abdomen is also visible in the right panel.
A newly eclosed Common Bluebottle resting near its pupal case.
A newly eclosed Common Bluebottle
References:
- The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
- The Butterflies of Hong Kong, M. Bascombe, G. Johnston, F. Bascombe, Princeton University Press 1999
- Don Herbison-Evans & Stella Crossley: "Caterpillar of Australia", Life History of Graphium sarpedon choredon.
