Venomous
Guides
Scolopocryptops sexspinosus
Eastern Red Centipede
Scolopocryptops sexspinosus, the eastern red centipede, is a large, venomous scolopendromorph centipede native to eastern North America. Adults reach approximately 69 mm in length and are typically orange to reddish-orange in coloration, though southeastern populations may appear browner. The species is active year-round and is notable for its rapid movement and ability to inflict painful bites. It is the only scolopendromorph centipede definitively documented in Canada.
Scorpiones
scorpions
Scorpiones is an ancient order of predatory arachnids, representing the oldest known terrestrial metazoans with fossil records dating back approximately 435 million years. Members are characterized by a pair of large pedipalps modified into grasping pincers, four pairs of walking legs, and a segmented metasoma (tail) terminating in a telson bearing a venomous stinger. Scorpions are the only arachnids that give birth to live young, with females carrying offspring on their backs until their first molt. They exhibit a unique ability to fluoresce under ultraviolet light due to fluorescent compounds in their exoskeletons.
Serradigitus
Sawfinger Scorpions
Serradigitus is a genus of small scorpions in the family Vaejovidae, commonly known as sawfinger scorpions. The genus contains more than 25 described species distributed across arid regions of the southwestern United States and northwestern Mexico. These scorpions are lithophilous, inhabiting rocky crevices and stone habitats. The venom of Serradigitus gertschi has been characterized through transcriptomic and proteomic analysis, revealing a complex mixture of ion channel toxins, enzymes, and other bioactive peptides.
Sicariidae
Sixeyed Sicariid Spiders, recluse spiders, violin spiders, sand spiders, assassin spiders
Sicariidae is a family of haplogyne spiders comprising three genera—Loxosceles, Sicarius, and Hexophthalma—with approximately 177-180 species. Members are characterized by six eyes arranged in three dyads (pairs), a distinctive trait among spiders. The family includes medically significant species such as the brown recluse (Loxosceles reclusa) and six-eyed sand spiders. All genera produce sphingomyelinase D or related tissue-destroying substances in their venom, unique among spiders. The family exhibits diverse ecological strategies: Loxosceles species are synanthropic and found nearly worldwide in warmer regions, while Sicarius and Hexophthalma are specialized desert dwellers with self-burying behavior.
Steatoda nobilis
Noble False Widow
Steatoda nobilis is a large theridiid spider native to Madeira and the Canary Islands, now established as one of the world's most invasive spider species. It has spread across Europe, North and South America, and other temperate regions, often becoming the dominant spider in urban environments. The species is of moderate medical significance: bites typically cause symptoms similar to bee or wasp stings, though some cases involve more severe reactions including bacterial infections from pathogenic bacteria carried on the spider's body. It constructs strong, irregular cobwebs with concealed tubular retreats and employs an 'attack wrap' hunting strategy to subdue prey.
Vespa mandarinia
Asian giant hornet, Japanese giant hornet, yak-killer hornet
Vespa mandarinia is the world's largest hornet species, native to temperate and tropical low mountains and forests of eastern Asia. It has been introduced to the Pacific Northwest of North America, where it was first detected in British Columbia and Washington State in 2019. The species poses significant threats to European honey bee colonies through coordinated group attacks, and its establishment could impact apiculture, ecosystems, and public health.