Jumping spider's fang. Coloured environmental scanning electron micrograph (ESEM) of the fangs on the end of a jaw (chelicera) of a jumping spider (family: Salticidae). Some chelicerae in spiders are hollow and contain, or are connected to, venom glands. The fangs are used to inject venom into prey. Also present here sensory bristles (setae), which form a spider's main sensory apparatus covering its body.