Harvestmen are an order of arachnids, with which they share many characteristics: their body is divided into two body regions (tagmata), the abdomen (opisthosoma) and the cephalothorax (prosoma); however, unlike in spiders, the juncture is often poorly defined. They have chelicerae, pedipalps and four pairs of legs. Most harvestmen have two eyes, although there are eyeless species.