MONEY SPIDER
SPIDERS are in the class Arachnida together with harvestmen, mites, and ticks and all have eight legs, can produce silk, and most have fangs able to inject venom into their prey.
There are around 650 species of spider in the UK, ranging from those with a leg span of just a couple of millimetres, to the 12cm leg span of the cardinal spider.
According to the Natural History Museum there are just 12 species of spider that are known to have bitten people in the UK, and bites from these spiders are extremely uncommon as, like most spiders, they are not aggressive.
It is extremely unlikely that a bite would develop into anything more than short-lived, low-level pain – some spider species have venom that might also cause some localised swelling or itching.
It should be remembered that spiders play an important role in our ecosystems as both predator and prey. They keep insect populations in check, and in turn they help to control the spread of disease and provide valuable food sources for birds and small animals.
There are 270 species of tiny UK spiders known as money spiders which are typically one to 7mm long belonging to the Linyphiidae family – over 40% of the spiders found in Britain.
Generally, they are a grey to black in colour, but some have distinctive markings and identification to species level requires microscopic examination. Whilst many people exhibit some fear towards spiders (arachnophobia), this does not always relate to money spiders, where superstition has it that if a money spider was to walk across you it will spin you some new clothes and in turn financial good fortune would come your way!
To increase their luck, it is a tradition that people would spin the spider around their heads by its web before letting it go. This superstition dates to Ancient Rome, with many Romans carrying coins with the images of spiders on them in the hope that poverty would be kept from their door.
The shiny black spiders that originated the name ‘money spider’ belong to the genus Erigone. To aid their dispersal, they use a method known as “ballooning” where the spider lets out a strand of silk into the air and air currents lift it into the air. This technique of dispersal is also known as aeronauting, and this method can often result in these tiny spiders landing on passing people.
Spiders belonging to the Linyphiidae family make sheet webs to catch their prey, which consist of horizontal sheets of silk with guide threads above and below the web which deflect their prey of flies and other small invertebrates into the web where the spider patiently waits.
The tiny “money spider” Tenuiphantes tenuis at 2mm to 3mm long is regularly recorded indoors and is believed to be the commonest spider in the UK. In lowland England, its habitats include ruderal vegetation, gardens, grassland, arable fields, wetland, heathland, and woodland, but it is perhaps especially associated with grasslands and is usually found in low growing vegetation and leaf litter.
Britain holds the world record for the largest ever spider’s web, created by tiny little money spiders on Kineton High School’s playing fields in Warwickshire in October 1998. The cobweb was shown to cover the entire 11.2 acres and features in the Guinness Book of Records.
Whilst this seems unbelievable, the population densities that these spiders can reach is estimated to be up to 4,000,000 in just two and a half acres of an ungrazed meadow.