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Booklice, also known as Psocids, are not actually true lice. While they look like lice in size and shape, booklice feed on fungi or mould. There are over 800 different types of Psocids.

The most common found in the UK is Liposscellis bostrycholphila, which cannot live outside in our climate as it is a tropical species.

They do not carry disease and are not classed as a health risk but in large numbers are classed as a nuisance pest.

They are found where there is high humidity as this will encourage the growth of mould and fungi. They can be found in stored food products and grain as well as under wallpaper and of course in books! Another place they are commonly found is on new plaster as it dries out as this offers the humid environment they need.
Booklice are very small 1-1.5mm in length and do not have wings. They cannot fly nor jump but can move quite quickly. They vary in colour from opaque white to grey/brown.

Adult females lay in excess of 60 eggs during the summer and the eggs can mature into adults in less than a month. This is dependent on the temperature, as is the case with most insects, and if the weather is cooler, fewer eggs are laid and maturity may take 3 months to complete.

Nymphs look like small versions of the adults and commonly have four nymphal stages. Booklice live for approximately 6 months.