Introduction
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INTRODUCTION Introduction This is a book about an often misunder- large spiders of ancient lineages, spending stood, sometimes feared group of animals, their lives underground. To be able to illustrated with beautiful images and identify and understand these creatures will informed by good science. Its simple aim is surely make the time you spend in natural to inspire interest in the natural world and places more vibrant and meaningful. its invertebrate wonders. Popular nature guides are well-trodden As a child, you might have been lucky ground, if not for spiders, then for many enough to play in local creeks, scooping other groups of animals. Most of all, birds up shrimps and water beetles in a jar and butterflies are the clear winners in the with rainbow fish, tadpoles, skaters and field-guide genre. But why stop there? Birds dragonfly nymphs. The aim of this book and butterflies might be just the beginning. is to inspire a similar wonder, delight and There is so much more out there. interest in tiny jewel-like spiders glinting If you are already a backyard naturalist, from their hiding places under leaves, or you may have ventured into the world of Who doesn’t like a good mystery? These spiders have a pebble-encrusted retreat suspended above a horizontal orb web pulled up at the centre. You don’t see that every day. Strangely, they seem to resemble spiders from Brazil, notably the Twelve-spotted Spilasma. Laurence Sanders discovered this unusual critter about 15 km west of Emerald in a strip of land between the highway and the railway line. Researchers at the George Washington University in Washington D.C. are on the case. DNA analysis so far has suggested this is a quite independent case of pebble-encrusted retreats and this spider is related to Arachnura, not at all related to Spilasma. Such mysteries are an almost everyday occurrence in arachnology and it is discoveries like this that make spidering so much fun. PHOTOS: LAURENCE SANDERS ♀ 4 mm 1 INTRODUCTION 2 INTRODUCTION insects, bugs, beetles and moths. There are their life cycles, behaviours, strengths and guides to help you identify Blue-banded weaknesses? Bees, Harlequin Bugs, Jewel Beetles, In answering these questions, not only Damselflies, Katydids, Lacewings and can you satisfy your own curiosity, you can Mantids. also contribute to the world’s knowledge And then you come to spiders. A few are of nature. Let’s face it, there couldn’t be a dangerous, most are bright and beautiful, better time to discover new nature – before while some are cheeky and disarming. it disappears. They belong to the world of the small, Before going any further, here’s a question. the world of invertebrates, a world which What’s your level of spider knowledge? How has irrevocably changed with the advent much do you know? Very little, quite a bit, of modern digital cameras, magnifying or lots? lenses and super-macro settings. New vistas If you answered lots, you are one of very have opened up, the colours stunning, the few Australians. structures complex and fascinating, the Apart from the Sydney Funnelweb, variety endless. St Andrews Cross, the Redback, the You now have the guide book in your Huntsman, Daddy Long-legs and Garden hands and you are ready to absorb spider Orb-weaver, most Australian spiders are knowledge. virtually unknown to the general public, But the very first thing one learns about even to many naturalists. Australian spiders is that our knowledge This is rather odd, in a world that explores is embarrassingly incomplete. Amazingly distant galaxies and the depths of the there are still many more unknown spiders oceans, because spiders are everywhere and than known ones. often close by. They occupy virtually every The current explorers of this field know possible habitat niche and every continent. all too well how much there is still to learn. There is even a small jumping spider If you join them you are very likely, within known to live at an altitude of 6,700 metres a few days, to discover an undescribed on Mount Everest, making it one of the species yourself, a species new to science. highest-altitude creatures on Earth. That’s exciting and pretty rare in biolog- Spiders are also early colonisers. When ical studies. There are not many groups the remains of the 1883 volcanic explosion of animals visible to the naked eye which of Krakatau were explored in 1884, the only have so many new species to discover in living thing on the island was a tiny spider, your own backyard or in nearby bush. found in a crevice. The adventure of discovering and naming Has anyone tried to calculate how many new species is just the beginning. How do spiders there might be, in total? these species function? How do they fit into Yes, actually. In 1939 British arachnol- food webs? What are their ecological roles, ogist W. S. Bristowe calculated that in one Sussex field there were at certain seasons more than 2,000,000 spiders to the acre. Opposite Sphecotheres vieilloti Australasian Figbird This translates to an amazing 500 per square ♂ Brisbane QLD PHOTO: ANNE JONES. Will spiders ever metre, which admittedly stretches credulity. become as popular as birds? Probably not. But surely they deserve more love and affection than they In 1999 Martin Nyffeler of the University presently get. of Bern reworked the calculations (using 3 INTRODUCTION data available since Bristowe’s original 1939 undescribed. Elsewhere this is not the estimates) finding a much more reasonable case. Occasionally previously-undescribed average of 200 per square metre. British species are found but they are a Whether there are 500 or 200 spiders per rarity rather than an everyday occurrence. square metre in optimal conditions, the In Japan and Germany previously-unde- simple fact is there are lots of spiders out scribed species are so rare, if you discovered there, and more than the ones you normally one you would probably be carried through see. There are spiders in the forest canopy, the streets on the shoulders of Ministers of under leaves, under bark, in leaf litter and the Environment. underground. There are also spiders so The total number of Australian spider small they are simply overlooked, and species is probably around 15,000 to others so well camouflaged you miss them 20,000. So far only 4,000 of them have been even in plain sight. described, a small percentage. In Australia, most of them are Euryattus ventralis Creeping Jumping Spider ♀ Cape York QLD PHOTO: ROBERT WHYTE. This is not a new species but it is the first recorded Australian specimen of this species normally found in PNG (and its neighbours). Thanks to its describer Jerzy Prószyński for identification. ♀ 8 mm ♂ 7 mm 4 INTRODUCTION Why are so many spiders unknown? eventually reaching the Nullarbor, while Australia is a vast, old continent and it has the far north drifted into the tropics where been on its own, separated from other land it came under the influence of a monsoon masses, for a long, long time. Around 80 climate. million years ago Australia and its most The result of all this has been plenty of recent companion, Antarctica, began slowly time for separate evolution. This is why separating. Africa and South America were more than 90 per cent of Australia’s inverte- far distant, even though they were still brate species are known nowhere else. attached to Antarctica. Western science has been operating in Around 46 million years ago Australia Australia for not much over 200 years, began moving rapidly north towards the nowhere near enough time to explore Equator, finally completing its separation every nook and cranny; secondly much of from Antarctica, becoming a true island Australia is harsh, making exploration is continent. Drying began in the north, difficult. Austracantha minax Australian Christmas Jewel Spider ♀ Glenmorgan QLD PHOTO: ROBERT WHYTE. A common and much-loved spider throughout Australia, sometimes found in large groups (with overlapping webs) in a range of habitats. ♀ 8 mm ♂ 4 mm 5 INTRODUCTION Is the challenge too big? Not really. It is designed to be a welcome addition to the certainly a big challenge, but citizen science libraries of naturalists, scientists, students, is helping. Will all Australia’s spiders be farmers, gardeners and the general public. known one day? Unlikely. Their diversity Everyone has a story about spiders and is mind-boggling. The closer you look, the most people have an opinion about them. more you find. One simply has to accept More and more the opinions are becoming this world of the small, the engine room of favourable as people learn spiders are ecosystems everywhere, is something that fascinating and wonderful to photograph. may never completely mapped, defined or The vast majority of spiders are harmless written down. But this shouldn’t stop us and all of them, in fact, are beneficial. trying. For many groups of Australian inverte- Australomisidia pilula Lozenge-shaped Crab Spider brates, progress is being made. Lavishly ♂ Central Highlands TAS PHOTO: ROBERT WHYTE. This spider was previously in the genus Diaea. A modern illustrated field guides cover more species of revision by Pawel Szymkowiak has found there moths, beetles, dragonflies, butterflies, stick are no genuine Diaea spp. in Australia. They have insects, even cockroaches, than ever before. all been moved to new genera, see page 352. This guide to the spiders of Australia is ♀ 6 mm ♂ 4 mm 6 INTRODUCTION Argiope keyserlingi St Andrews Cross Spider ♀ Brisbane QLD PHOTO: ROBERT WHYTE. This is one of the more recognizable and easily-identified Australian spiders. ♀ 20 mm ♂ 5 mm 7 FROM ARACHNOPHOBIA TO ARACHNOPHILIA From arachnophobia to arachnophilia Fear of spiders is learned.