Arachnids
Arachnids have eight legs, two body sections and no antennae, which separates them cleanly from insects however often the two get confused. The group covers spiders, scorpions, mites, ticks…
About arachnids
Arachnids have eight legs, two body sections and no antennae, which separates them cleanly from insects however often the two get confused. The group covers spiders, scorpions, mites, ticks and harvestmen, and it is far older than the insects it preys on. Nearly all spiders are venomous and almost none are dangerous to people; the venom is a hunting tool scaled to insect prey. Silk is the group's real innovation — stronger by weight than steel, produced in several different types by a single animal, and used for webs, wrapping, safety lines, egg cases and, in some species, ballooning across long distances on air currents. As predators of insects they exert a very large and largely unnoticed influence on the systems they live in.
Arachnids with a full profile
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Where arachnids are recorded
| Region | Climate | Species |
|---|---|---|
| Southern Africa | Warm and sunny with a summer rainy season. | 54 |
| Mexico & Central America | Warm and tropical with a strong rainy season. | 33 |
| North American Desert | Scorching dry days and surprisingly cool nights. | 26 |
| Arabia & the Middle East | Blistering desert heat with very little rain. | 24 |
| New Zealand | Mild, wet and temperate. | 20 |
| Mainland Southeast Asia | Hot and tropical with a heavy monsoon. | 18 |
| Indian Subcontinent | Hot, ruled by the dramatic monsoon rains. | 17 |
| Eastern North America | Four full seasons — humid summers and snowy winters. | 16 |
| Andes Mountains | Thin, cold mountain air — sunny days and frosty nights. | 13 |
| European Woodlands | Mild, temperate seasons with cool rain and gentle summers. | 10 |
| Coral Reefs & Oceans | Warm, sunlit tropical seas in the shallows; cold and dark in the deep. | 10 |
| American South & Everglades | Hot, humid and subtropical with heavy summer storms. | 10 |
| Caribbean Islands | Warm, breezy and tropical all year. | 7 |
| Sahara & Deserts | Scorching days above 45°C and surprisingly freezing nights. | 6 |
| African Rainforest | Hot, humid and rainy almost every day, around 25°C. | 6 |
| Amazon Rainforest | Warm and extremely humid with heavy rainfall all year round. | 6 |
| Japan & Korea | Four seasons, from the snowy north to the mild south. | 6 |
| Siberian Taiga | Brutally cold winters and short, mild summers. | 6 |
| Madagascar | Tropical and warm with distinct wet and dry seasons. | 5 |
| West Africa | Hot and humid by the coast, drier toward the Sahel. | 5 |
| Australian Outback | Hot, dry and blazing-bright across the interior. | 4 |
| Himalayas & High Asia | Bitterly cold with thin air, snow and fierce winds. | 3 |
| North American Wilds | Four strong seasons with snowy winters and warm summers. | 3 |
| New Guinea & Melanesia | Hot, humid and rainy all year. | 3 |
| China's Bamboo Forests | Cool, misty and damp in the mountain forests. | 2 |
| African Savanna | Hot all year with dramatic wet and dry seasons, typically 25–35°C. | 1 |
| Arctic & Tundra | Long frozen winters far below 0°C and a short, cool summer. | 1 |
| Antarctica | Earth's coldest, windiest place, plunging to −60°C. | 1 |
| Southeast Asian Jungle | Hot and steamy with monsoon downpours. | 1 |
| Pantanal & Cerrado | Hot, with a flooded wet season and a dry winter. | 1 |