Spiders are a large group with approximately 2,500 species. The bodies are divided into two regions, the cephalothorax (head and thorax are fused to form one region) and the abdomen. The mouthparts, eyes and legs are all located on the cephalothorax. Typically there are 8 eyes, but many species have fewer. The abdomen is unsegmented. The spinnerets, which are used in creating silk, are located at the tip of the abdomen.