IT'S A LAC'S LIFE Amanda Rofe investigates the hitherto mysterious world inhabited by the shellac industry
T
he lac (Laccifer lacca) is one of 200 species of scale insect that attach themselves in great numbers to plants and trees. It is exploited primarily for it resinous secretions, which form the basis of shellac — a multi-purpose substance with a wide variety of commercial applications. Some defenders of the use of shellac — including companies claiming 'cruelty-free' credentials — claim that during its production no insect is harmed. This is untrue.
BROODY The life cycle of a lac insect spans approximately six months and consists of four stages: egg, larva, pupa and adult. The 'brood lac' ('mother cell') containing a female lac insect is tied on to new twigs of'lac host trees', where she
Shellac has been credited with providing the catalyst for the modern plastics industry
The V e g a n , S u m m e r 1997
thrives. After the trees have been 'infected' with brood lac, the whole process requires litde or no human intervention until harvest. Following fertilisation by a male (see below), the resulting red larvae, roughly 0.5mm long, crawl out of the brood lac and settle on the twigs. At this stage both the male and female larvae live off the sap of the trees. They insert their long suctorial mouth part, or proboscis, into the tree and draw out sustenance. A secretion is exuded from their bodies which, in essence, is a protective covering to fend off attacks by predators. This secretion forms into hard resinous layers which completely cover their bodies, leaving small anal and breathing openings. The insects mature into adults within this protective layer (known as the 'cell') — both the male and female larvae become sexually mature in about eight weeks. Only the male insect undergoes a complete metamorphosis; it loses its proboscis and develops antennae, legs and a single pair of wings. The male cell, somewhat longer than the female equivalent, contains a round trap door
through which the male insect emerges, sometimes winged, to walk over the females, fertilising them. After fertilisation he dies.
SHELL-LIKE
The female cell is shorter and roundish in shape. The female retains her mouth part but fails to develop wings or eyes. Her ovaries contain lac dye, a crimson fluid resembling cochineal (a food/ drink colouring consisting of the dried bodies of the cochineal insect, Coccus cacti). While developing rudimentary antennae and legs, for all intents and purposes she becomes an immobile shell-like organism with scant resemblance to an insect. Females are little more than egg producers. The female increases in size to accommodate her growing number of eggs. Lac resin is secreted at a faster rate and a continuous layer coalesces or grows into one long crusty knobbly cell. After fourteen weeks the female contracts, allowing light into the cell, and lays her eggs. When the eggs hatch, the larvae appear, and the whole cycle begins again.