No species has all seven, but orb-web weavers have five. Spiders have structures called spinnerets on their abdomen, usually on the underside to the rear. These are the silk-spinning organs. Different ...

Each group of arthropods is defined by a unique arrangement of tagmata: for instance, insects have a head, thorax, and abdomen, while spiders possess a cephalothorax and abdomen. Although these ...