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THE SLOW-WORM Lampyris noctiluca
The glow-worm is probably our best known
beetle. It has been mentioned in poems and
songs for several centuries. Lampyris is
nat, however, a typical beetle in appearance.
It starts life as a faintly glowing egg which
hatches into a flat larva or "worm". The
larvae feed mainly on slugs and snails by
injecting a liquifying enzyme into their prey,
then sucking up the liquid. The pupal stage
is brief and still resembles the larval stage.
When the adult beetle emerges, if female, it is
still similar to the larva, being slightly
broader and with more complex antennae and
legs. It glows with a pale yellow/green
light. This light comes from enzymic
oxidation of a chemical under the transparent
cuticle of the underside of the last three
segments and can be turned on and off by the
beetle. The male is more beetlelike with very
large eyes, which are used to see the females'
glow. They fly well with their wings and are
strongly attracted to artificial lights.
I first came across glow—worms in Suffolk about
30 years ago. Two females were glowing on
grass by the road in the rain. The glow was
as bright as a cigarette butt, and as I tipped
them into my cupped hand it was hard not be
slightly apprehensive - was I really not going
to be burned? But, of course, the light was
cold. The light was not bright enough to read
by
More recently I found a larva in Thorndon
Country Park at the edge of a pine plantation.