Butterflies of
Thailand, Malaysia &
Borneo
Branded Imperial
Eooxylides tharis
GEYER, 1837
Family - LYCAENIDAE
subfamily - THECLINAE
Tribe - EUMAEINI
Eooxylides tharis distanti, female, Tapah, West Malaysia ©
Adrian Hoskins
Introduction
The Theclinae ( Hairstreaks ) are found worldwide, with about 270
representatives in Sundaland, the region that encompasses the Malay
peninsula, Borneo, Sumatra, Java and Palawan.
There are several genera which contain species
with long tails, orange undersides, and black and white markings in
the distal area, including Thamala,
Eooxylides,
Drupadia, Cheritra,
Neocheritra,
Thrix and Zeltus.
Eooxylides tharis is
certainly one of the most beautiful species from the genera listed
above. It is recognised by it's particularly brilliant orange
underside colouration, very distinctive markings, and
extraordinarily long and twisted tails. The upperside wings are
blackish brown, with broken white markings in the distal area of the
hindwings.
There are arguably
11 species of Eooxylides, although many
workers regard the majority of these as being subspecies of
tharis, occurring variously in
Thailand, West Malaysia, Singapore, Borneo, Sumatra, Palawan, Java
and some of the smaller islands of Indo-China.
Most authorities however agree that
etias from Borneo, and
meduana from the Philippines are
distinct species.
Habitats
This species is found in wet rainforest areas at elevations between
sea level and about 1000m.
Lifecycle
In August
2004 at Tapah Hills in Malaysia, I observed a female ovipositing on
a woody sprig at the side of a forest road. The eggs were white and
were laid in loose clusters of about 10-15, wrapped around the tip
of the sprig, about 0.5m above ground level. I was unable to
determine the species of plant. The only recorded larval foodplant
is Smilax bracteata, a common forest
vine.
The larva is green, suffused on the thorax and at
the tail end with red. It is smooth-skinned, ovoid, flattened, and
has what could be described as a lip or rib around its lower half,
enabling it to squat limpet-like to it's substrate, with it's legs
completely hidden. This strongly suggests that it needs to protect
its soft undersurface from the ants which attend it. ( Seufert &
Fiedler found that about 50% of tharis
larvae were attended by ants ). The green pupa has the wing cases
suffused with white at their base, and with reddish around the wing
edges.
Eooxylides tharis distanti, male feeding at bird dropping,
Tapah, West Malaysia ©
Adrian Hoskins
Adult behaviour
The butterfly tends to skip
purposefully from perch to perch, searching for food sources which
include bird droppings and aphid secretions. Once settled they are
usually reluctant to move, and oblivious to human disturbance,
particularly if they are feeding.
Males are commonly found
in small groups of about 3 or 4 on
the stems of bushes in shady areas of disturbed forest, having been
attracted by the sweet "honey-dew" secretions produced by aphids and
membracids. At such sites there are invariably at least a dozen ants
sharing their meal, but the ants do not molest the butterflies, which
are possibly protected by their chemical properties. When feeding they
habitually walk around the stems, each butterfly slowly rotating on
its own axis as it avidly probes the sugary secretions with its
proboscis. On more than one occasion I've found males head-locked
together, apparently the result of an eagerness to feed, rather than
aggression.
Females are usually encountered
singly, when searching for oviposition sites. |
