Opiliones
Harvestmen have small round bodies with eight very long, very thin legs. Like ticks and mites, harvestmen have evolved a tight connection between the two body sections that other Arachnids have. Their whole body is one round unit. On either side of their mouth they have short appendages called pedipalps that they use to hold food while they chew it.
These long-legged arachnids are found all around the world. They are most diverse in tropical Southeast Asia and South America, but there are harvestman species everywhere, even in much colder regions.
Harvestmen need humid places to live. They are most often found in forests and caves, climbing on rocks and vegetation.
These animals have to shed their exoskeleton in order to grow. They don't change their shape much as they grow, just get bigger and grow longer legs. Often they hang upside down while shedding.
Usually only one year.
Not much is known about the behavior of this group. Some are active at night, some in daylight.
Harvestmen have eyes, but don't see very well. They probably rely on touch and smell
Harvestmen eat very small invertebrates, and scavenge on larger dead ones and dead plant material.
These animals have large glands that produce toxic chemicals to keep predators away. They also can shed their legs, and move fast even if they loose a couple. If a predator grabs a leg, the harvestman will just leave it behind, still twitching and distracting the predator, while the rest of the animal gets away.