Butterflies of
Thailand, Malaysia &
Borneo
Long-tailed Blue
Lampides boeticus
LINNAEUS, 1767
Family - LYCAENIDAE
subfamily -
POLYOMMATINAE
introduction
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habitats |
lifecycle |
adult behaviour
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Lampides boeticus, Ringlet, Cameron
Highlands, West Malaysia |
Introduction
The Long-tailed Blue, or
Pea Blue as it is often called, is the sole member of the genus
Lampides. Despite its small size and apparent
fragility it is strongly migratory, able to cross seas, oceans and low mountain
ranges with relative ease. It is one of the commonest and most widespread
species in the Old World, breeding in southern Europe, almost throughout Africa,
and across southern Asia to Indonesia and Australia, and reached New Zealand in
1965.
The butterfly
reached Hawaii in 1882 but has not yet reached the Americas, although it will
almost certainly manage to do so within a few years, probably as a result of
being accidentally introduced with an imported plant.
In the Oriental region
boeticus is widespread and common, largely due to
the use of one of its larval foodplants Crotalaria
as a cover plant in rubber plantations.
On the upperside males are pale
blue with narrow dark borders. Females are dark earthy brown, with a slight
flush of pale blue scales at the base of the wings. The pattern on the underside
is unique, so this species is unlikely to be confused with any other.
Lampides boeticus, Orissa, India
( image
© Haraprasan Nayak )
Habitats
In Malaysia
this highly adaptable species is found in many different types of environment
including coastal habitats, open grasslands, riverbanks, plantations ( e.g. oil
palm, tea, eucalyptus, rubber ), parks, gardens, quarries, temperate forests and
along roadsides. It occurs at all elevations up to about 1500m.
Lifecycle
The eggs are
china-white and covered with a network of reticulations. They are laid on the
flowers, sepals and flower stalks of herbs and bushes in the family Fabaceae
including
Alhagi,
Astragalus, Cajanus,
Canavalia,
Chamaecytisus, Cicer,
Clianthus,
Crotalaria,
Cytisus,
Dolichos, Helianthemum,
Kennedia, Lathyrus,
Lotus, Lupinus,
Medicago,
Onobrychis,
Phaseolus,
Pisum,
Psoralea, Pueraria,
Sesbania, Spartium,
Sutherlandia, Swainsona,
Trifolium,
Ulex,
Vicia and
Virgilia.
The larvae when fully grown are cylindrical, and occur in several colour forms
including dark green, yellowish green, and pearly white. All forms have a brown
dorsal stripe, reddish lateral streaks and a brown head. The larva has a honey
gland on the 7th abdominal segment which attracts certain ant species which milk
it for the secretion. The presence of the ants is undoubtedly beneficial in
providing a degree of protection against parasitoid wasps and flies. The larva
is cannibalistic at all stages of its life, with the result that only one larva
survives on each plant.
The smooth rounded chrysalis is creamy or pale brown, with a dark dorsal line.
It is usually formed at ground level, attached to a dead leaf.
Adult behaviour
The migratory
nature of the butterfly means that adults can be seen singly almost anywhere,
but normally in the areas where it breeds several can be seen flying together
around leguminous herbs and bushes.
Both sexes nectar at a wide variety of wild and cultivated flowers. Males also
visit damp ground to imbibe mineralised moisture, usually aggregating with other
Polyommatine species.
The antennae-like "tails" on the hindwings, together with the orange, silver and
black "eyespot" at the tornus act together to create the impression of a false
head, and divert the attention of birds away from the body. When the butterfly
first settles it immediately turns around, and when it is feeding it often walks
about in tight circles, thus a predator is never quite sure which direction it
is facing. It also oscillates its hindwings causing the tails to wiggle like
antennae. This reinforces the back-to-front illusion, and probably causes
attacking birds to aim at the tail instead of the head of the butterfly,
enabling it to escape relatively unharmed, leaving the bird with nothing but a
piece of detached wing in its beaks.
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