The Sumatran Tiger Beetle



EXCERPT FROM “A GENERAL HISTORY OF THE INSECTS OF SUMATRA” by
Simeon Van Berger Op Zoom, translated by Jules Fischer, published in Britain by Random
House, 1958.
In general it is the size of Sumatran insects that is most remarkable, rather then any
general deadliness to the species of man; the density, humidity and fecundity of the Sumatran
jungle, especially in the Achinese highlands, guarantees that most insects found there will be large.
Most are harmless, as hopefully this work has done at some lengths to assuage the reader in lands
remote and altogether more civilised then the isle of Sumatra.  There is, however, a curious but
also potentially lethal exception to be found on this tropical island, to which this chapter will now
turn.  The Sumatran Red Tiger Beetle, or Vorocarnisae sumatranus, sole amongst predatory
insects, has a dangerous habit during its larval stage of eating out the insides of a human skull,
brain and all.  Despite this terrifying behaviour, the Sumatran Red Tiger Beetle is practically
unknown outside of Sumatra.  We hope to rectify this situation somewhat.
The Sumatran Red Tiger Beetle is a member of the Cicindelidae family, better known to
the public as the tiger beetles.   Tiger beetles as a whole are identifiable by their large bulging
eyes, long, slender legs and large curved mandibles, in addition to an inability to fly well and a
quickness of foot on the ground; those species common to North America are ground-dwelling
predators, often startled out from under rocks during the day or seen prowling at night.
Vorocarnisae sumatranus shares some of these characteristics, particularly as it is equipped with a
heavy pair of mandibles and long slender legs.  In other ways it is morphologically distinct.
The eyes, for instance, are very diminutive, especially in the adults, and it is unlikely that
vision is heavily used in hunting.   Although its antennae are filiform, the Sumatran lacks the
fivefold segmentation of tarsi found in other Cicindelidae. Indeed, so distinct is the Red Tiger
Beetle from all other species of Cicindelidae that it has a genus all to itself; the closest living
relatives are the large South African beetles of the genus Mantichora.  Even then, the Sumatran
Red Tiger Beetle stands apart, notably in its bizarre and lethal form of reproduction.  To this day,
it is the only species of tiger beetle known to be deadly to man.
The mature adult of the species is not as active a hunter as other members of the family
Cicindelidae.  Its body is considerably more rotund, its double pair of mandibles arranged in a
vertical rather then lateral fashion.  Along its elytral are several brightly coloured ovals, the
vestiges of special glands, phosphorescent in nature, present on the larvae.  Like all tiger beetles,
the Sumatran is brightly coloured, especially on its legs and underside of the thorax, with the
elytra being much duller, variegated only by alternating stripes of light and dark browns.  The
elytral, as in most tiger beetles, is fused and incapable of opening, forming an excellent protective
shield.  The pronotum teeth are especially smooth and well-linked together.
Nearly 2.5 inches in length, Vorocarnisae sumatranus is primarily an ambush predator,
waiting carefully for prey as large as frogs.  The presence of numerous fine hairs on their limbs
allows them to sense vibrations made by prey, whereas the fused tarsi are heavily clawed and
well-adapted for climbing and digging burrows.  The adults are nonetheless usually found on the
forest floor, often hidden by fallen logs or leaves.  They are most commonly seen by humans
around or on corpses, which earned the beetle its popular name in Indonesian, badanmak, or
‘body-eater’.
Like all beetles, Vorocarnisae sumatranus, goes through holometabola, or complete
metamorphosis, changing from a worm-like larva to a quiescent pupa to a beetle during its life.
The Sumatran Tiger Beetle depends upon the decaying remains of higher animals for
reproduction.  The adult female, after a short mating season, lays a cluster of eggs in a cavity on
the corpse of a large animal like a water buffalo or orangutan.  The eggs hatch very quickly, and
the new oligopod grubs, brightly coloured with alternating stripes and possessing a jaw structure
much better suited to chewing and rasping then the adults, burrow into the decaying body through
an orifice.  For unknown reasons the larva have active phosphorescent organs, although this may
be related to driving away other scavengers or startling predators.  The larva, after upwards of ten
days, emerges and crawls away to pupate.  Although this in itself can be ghastly to humans, it is
no worse then what maggots or other scavengers do.  Vorocarnisae sumatranus,, however, has
adapted a considerably more terrifying way of feeding.
Somehow, long ago, the Sumatran Red Tiger Beetle adapted itself to lay eggs in a living
host.  The eggs are usually deposited in the ears, and after hatching, the larva, very small, quickly
crawl down the main cavity and find their way into the brain, where vast amounts of protein can
be rapidly accumulated for growth.  This is extremely painful for the victim, who is often aware of
a kind of burning sensation in the immediate hours afterwards.   The larva usually devour non-
essential sections of the brain first, leaving the basic pulmonary, cardiac and sensory systems
operating until the end.  The pain grows worse and worse with every passing day. In the final
phase of this predation, the victims eyes roll back into the head due to the larva’s actions upon the
main optic nerves.  Still functioning, the victim’s eyes can see the greenish glow of the larva at
work.  Death is almost always inevitable, and there is no known method of prevention or removal
of the larva, short of cutting open the head or pouring pesticide down the ear.  Neither treatment
is likely to save the victim.  Luckily, because the Sumatran Red is a relatively sluggish animal, and
because they are easily spotted, deaths are rare, even if highly visible.  The victim is often
rendered near insane by the larva, perhaps leading to Achinese legends of demonic possession.
The first widespread knowledge of the Sumatran Red only came, however, after the Dutch
invasion of Aceh in the 1870’s; the Dutch soldiers, unused to jungle warfare, often fell prey to the
Vorocarnisae sumatranus, and thus the symptoms came to be known as ‘Dutch madness’.