Why you should be glad of ‘scorpions’ in your house

Nature: Rex Hancy on the myserious world of the pseudoscorpion.

The discovery of a pseudoscorpion on a tiled floor here caused great excitement. That was many years ago and led to many other encounters as we learned how to find and identify the tiny creatures. How easy it would have been to have missed that initial find as it was a mere couple of millimetres long. The first question was how it had arrived here.

The answer was by taking a major detour from one of the bird’s nests under our tiles which happened to be just above an open window. There is no chance of a repetition. We have had no nests there since the feeding grounds were lost to wildlife a quarter of a century ago.

Other individuals of other species turned up when we were hunting for small spiders in the leaf litter on woodland floors. That was during our spider identification phase. There was a strong ink because psuedoscorpions are near relations of spiders and as such cannot be classified as insects. The list of likely habitats to search is very long.

We have only just over a couple of dozen species in this country but between them they have adapted to life in most habitats. Some may be found in houses but being so small are rarely found. Our number one was certainly in the wrong place at the wrong time. Normally psuedoscorpions keep out of conspicuous, well-lit places.

Having a reasonable population indoors is no bad thing. One of our commonest species is rather fond of booklice so a cupboard full of dusty books is their kind of heaven. The same species is also partial to house dust mites which are extremely difficult to control so a little help from even such tiny friends should be welcomed. In spite of being the victims of chemical warfare clothes moth larvae and carpet beetle larvae occur. Step forward pseudoscorpions and do your duty!

Anyone not using a strong lens with the creature confined in a box is not likely to see the recognition features. In simple terms we have to imagine a really diminutive scorpion. There is the obvious lack of one very significant feature. The fearsome-looking stinging tail of a true scorpion is completely absent.