Size isn’t everything…

It is a good few years now (around eight?) since I really got stuck into my present interest in spiders. Surrey is the spider-capital of the UK, so I’ve now managed to find and identify a significant proportion of the British list, which currently stands at around 670 species. Surrey hosts about 63% of them, mainly down to our lowland heathlands which are a spider-paradise. 

Fangs to spinners, the bodies of the largest British spiders are around 20mm (including the great fox, which I re-discovered in 2020). Other contenders for the largest are the grey bear-spider of river-shingle shorelines north of Yorkshire and in Wales, and the green-fanged tube-web of maritime urban built-heritage structures, in London and along the south coast.

But a huge majority are a mere couple of millimetres in length at best, including most of the largest family – the Linyphiidae or ‘money-spiders’. To study these, it often feels one is entering Marvel’s quantum realm. It takes digital microscopes and high-magnification hand-lenses to reveal them. Anyone who knows anything about spider taxonomy is aware that the mature, adult reproductive structures are the clinching diagnostic features. The size of these on a 1mm-long spider – well, you see my point… 

Collecting, or sampling, spiders is greatly enhanced by use of a D-Vac system, which is really a leaf-blower stuck in reverse. It sucks tiny insects into a collection bag or sieve.  It is only as one upgrades to the D-Vac that the full enormity of species at the smaller end of the spider size-spectrum is revealed. Which in turn generates a shedload more lab-work, of course. 

The excitement to be found at the end of a microscope must not be under-estimated. Many of the males of the smallest money-spiders are equipped with truly bizarre carapaces (the head and thorax combined in spiders), with the anterior (front) head area contorted into extraordinary structures that bear their eyes on towering pillars, elevated plateaux, and other weird bulbosities. Why money-spiders have these features, apart from to improve their visibility, is anyone’s guess.

Worlds-within-worlds

When you consider the sheer faff that serious arachnology demands, it is hardly any wonder that arachnids have been so notoriously ‘under-recorded’.  The same can be said of most other forms of entomology (the study of invertebrates), not to mention bryology (mosses and liverworts), mycology (fungi), etc. 

And yet, we are still prepared to assess the current conservation status of these species, based on their national records database, accumulated over the decades and in previous centuries. To suggest that such assessments must be viewed as somewhat provisional, even tenuous, may appear slightly heretical – but I’m going to anyway. 

On reflection though, the intense attention to detail that the microscopic study of invertebrates requires might be just the thing for our current zeitgeist. 

Plus, as inclusion and acceptance grows, entomology is perfect for autistic people with our specialities and skills, where only the most gifted of tunnel-visionaries have the patience and excitement for such demanding work.

So, on I will forge, descending Alice’s rabbit hole with “Drink Me” flask held tightly in my paw, as I continue to explore the vast universe of the super-small. Just this year, a tiny, untypically pale money-spider popped new into my consciousness, whilst looking for something entirely different on the chalk downs above the Eurotunnel entrance at Folkestone. 

I quickly narrowed this down to a Tapinocyba-like species, but only when we both arrived home did I discover the species to be Tapinocyboides pygmaeus, a downland species undoubted but never before recorded in Kent. This attractive little spider was only discovered in England in 1951 and is officially still ‘Nationally rare’ (recorded in less than 16 of the 3,860 10x10km squares in the UK). But as its ‘Data Deficient’ conservation status is forced to admit in this case, they could be far more widespread in limestone habitats across the country…

For further information or to learn more about spiders visit Spider Recording Scheme.

Author bio: Mike Waite is Director of Research & Monitoring at Surrey Wildlife Trust and a practicing ecologist of some 40 years experience. His thirst for the discovery of fresh species to add to his repertoire is undiminished and only getting keener…