The ant-lion is a small delicate insect
that looks like a brown damselfly. The adult ant-lion has a weak flight and is
most commonly found in vegetation in sandy areas especially along the west
coast. Ant-lions have a worldwide distribution being particularly common in
arid sandy habitats. There are about 2,000 species. About 12 species occur in
the Maltese islands.
In most European and Mediterranean
countries its name in some way or the other describes these insects as
predators of ants. In Maltese they are known as qerd in-nemel. This is
because the larvae feed mainly on small insects especially ants. The adults of
some species feed on nectar and small pollen while others are predators of
small arthropods.
The larva of the ant-lion digs a pit in the
sand by crawling backward, using its abdomen as a plough to shovel up the soil.
It uses one front leg to place heaps of particles on its head, which it then
flicks away from the area in which it is digging. It continues working in this
way as it moves sideways and inwards towards the centre creating a deep pit
with steep sloping sides. When the pit is complete it settles down at the
bottom buried in the sand with only its jaws protruding.
Any insect
venturing over the edge of the pit will find it difficult to maintain a hold on
the loose sand and slips to the bottom where it will find the larva waiting
with open jaws. If it tries to run up the steep sides the larva will shower it
with loose sand to make it fall back to the bottom of the pit. There is no need
for the larva to hit the escaping prey with sand. By removing sand from th
ebottom of the pit, the larvae causes the sides to collapse bring the prey down
with it.
The ant-lion
larva can capture and subdue a variety of insects and even small spiders. The
projections in the jaws are hollow and it uses them to suck out the contents of
its victims. It then flicks the dry carcass out of of the pit and arranges the
pit by throwing out collapsed material from the centre to the sides making them
as steep as possible in readiness for the next victim.
This article was published in The Times on 1 July 2009
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