abstract:The chelicerae are mouthparts of the Chelicerata, an arthropod subphylum that includes arachnids, Merostomata (horseshoe crabs), and Pycnogonida (sea spiders). Additionally, some chelicerae, such as those found in spiders, are hollow and contain (or are connected to) venom glands, and are used to inject venom into prey or a (perceived) threat.