Midgets to monsters

Armoured Spider.

A few spiders are so small and live such hidden lives that most of us never see them. Others are enormous.

Some of the smallest spiders in the world are anapid spiders, sometimes called armoured spiders because of the cuticular plates on their pinhead-sized bodies. Small spiders like anapids are usually found in damp, cool habitats like forest leaf litter and moss because their small bodies can lose water rapidly in dryer conditions. The largest spiders in the world include the South American Goliath Tarantula, some so big their legs can span a dinner plate. Such spiders may take decades to reach such a size. However, spider size is limited, partly because their respiratory physiology becomes less efficient at very large sizes.

Bodies bizarre

Many spiders have unusual body shapes and colours.

Bizarre bodies can be helpful to spiders in various ways - to deceive and ambush prey, to capture particular sorts of prey, to avoid being eaten and to attract mates.