Latrodectus spp. toxins outside venom glands: past, present and future

Latrodectus spp. are one of the highly poisonous spiders known in the world. Interestingly, the spiders not only produce and secrete toxins by their venom glands, but also have toxic components in other parts of the adult spiders, and even in the newborn spiderlings and unhatched eggs. The venom and venom toxins secreted by their venom glands have been quite extensively studied and, comparatively, the study on the toxins outside venom glands is limited. Although the toxins outside venom glands were discovered at a very early time, it is not until recently that the molecular basis and mechanism of the toxicity outside venom glands have been relatively systematically investigated, which have significantly expanded our understanding of the spider toxins. This review summarizes the progresses in research on Latrodectus spp., particularly black widow spider, toxins outside venom glands, with an emphasis on toxins from the spider eggs.