Thomisidae
Guides
Xysticus emertoni
Emerton's Crab Spider
Xysticus emertoni, commonly known as Emerton's crab spider, is a species of ground crab spider in the family Thomisidae. It occurs across a broad transcontinental range spanning North America and Eurasia, including the United States, Canada, Russia, and Central Asia through China. As a member of the genus Xysticus, it exhibits the typical crab spider body plan with laterally extended legs adapted for ambush predation. The species has been documented as prey for spider wasps in the genus Dipogon.
Xysticus fraternus
Brotherly Ground Crab Spider
Xysticus fraternus is a species of ground crab spider in the family Thomisidae. It occurs in the United States and Canada. Like other members of the genus Xysticus, it is an ambush predator that does not construct webs to capture prey. The species is part of a diverse genus of crab spiders that includes many habitat generalists.
Xysticus funestus
mournful ground crab spider, sad ground crab spider, deadly ground crab spider
Xysticus funestus is a ground crab spider in the family Thomisidae, native to North America. It is one of many ambush-hunting crab spiders that rely on elongated front legs to capture prey. The species has been documented in field observations as an adult in early spring and has been recorded as prey for the spider wasp Dipogon calipterus. Despite its alarming common name "deadly ground crab spider," it poses no medical threat to humans.
Thomisidaeground-crab-spiderambush-predatorNorth-Americaballooningspider-wasp-preynon-medical-bite-riskspring-activityoverwintering-adultgravid-female-March-observationColoradoWisconsinDipogon-calipterus-prey-recordconcrete-path-habitatmailbox-post-observationforest-edgeleaf-litter-overwinteringmisleading-common-nameKeyserling-1880Xysticus gosiutus
Xysticus gosiutus is a species of crab spider in the family Thomisidae, first described by Gertsch in 1933. As a member of the genus Xysticus, it belongs to a group of ground-dwelling ambush predators commonly known as ground crab spiders. The species is recorded from the United States and Canada, with specific distribution records from Alberta and British Columbia. Like other Xysticus species, it is likely an ambush hunter that relies on camouflage and rapid leg extension to capture prey.
Xysticus gulosus
Xysticus gulosus is a species of crab spider in the family Thomisidae, described by Keyserling in 1880. It belongs to the genus Xysticus, a diverse group of ground-dwelling ambush predators commonly known as ground crab spiders. The species is distributed across North America, with confirmed records from the Canadian provinces of Alberta, Manitoba, and Saskatchewan. Like other members of its genus, it likely employs a sit-and-wait hunting strategy, using its enlarged front legs to capture prey.
Xysticus locuples
Xysticus locuples is a species of crab spider in the family Thomisidae, first described by Keyserling in 1880. It is distributed across North America, with records from Canada and the United States including Alberta. As a member of the genus Xysticus, it belongs to a group of ground-dwelling ambush predators commonly known as ground crab spiders. The genus Xysticus is known for species that employ ballooning as a primary dispersal mechanism, particularly in spring and fall.
Xysticus luctuosus
Xysticus luctuosus is a species of ground crab spider in the family Thomisidae, first described by Blackwall in 1836. It has a broad distribution spanning North America, Europe, Turkey, the Caucasus, Russia (from European to Far East regions), Kazakhstan, Iran, and Central Asia. As a member of the genus Xysticus, it exhibits the characteristic crab spider body plan with laterally extended legs adapted for ambush predation. The species has been documented in 45 iNaturalist observations, indicating moderate citizen science engagement.
Xysticus montanensis
Montane Crab Spider
Xysticus montanensis is a species of crab spider in the family Thomisidae, first described by Keyserling in 1887. It is distributed across western and central North America, with records from Canadian provinces including Alberta, British Columbia, and Manitoba, as well as the United States. As a member of the genus Xysticus, it shares the typical crab spider morphology and ambush-hunting behavior, though species-specific details remain limited in the literature.
Xysticus obscurus
Xysticus obscurus is a species of ground crab spider in the family Thomisidae, first described by Collett in 1877. It is a holarctic species with a broad distribution spanning North America, Europe, and across Russia from European Russia to Siberia. As a member of the genus Xysticus, it is an ambush predator that does not construct webs for prey capture. The species has been documented in Alberta, Canada, and is part of a genus known for ballooning behavior as a dispersal mechanism.
Xysticus paiutus
Xysticus paiutus is a species of crab spider in the family Thomisidae, first described by Gertsch in 1933. Like other members of its genus, it is a ground-dwelling ambush predator. The species occurs in the southwestern United States and Mexico. Information on its biology and ecology remains limited.
Xysticus pellax
Xysticus pellax is a species of crab spider in the family Thomisidae, first described by O. Pickard-Cambridge in 1894. It is native to North America, with records from Canada and the United States. Like other members of its genus, it is a ground-dwelling ambush predator.
Xysticus possiblefunestus
Xysticus possiblefunestus is a species of crab spider in the family Thomisidae. The genus Xysticus comprises ground-dwelling crab spiders that are ambush predators, typically found in terrestrial habitats across the Northern Hemisphere. This species belongs to a diverse genus with over 360 described species worldwide. Like other Xysticus species, it likely exhibits the characteristic crab-like posture with enlarged front legs used for seizing prey. The specific epithet "possiblefunestus" suggests taxonomic uncertainty or similarity to Xysticus funestus, a European species.
Xysticus punctatus
Punctated Ground Crab Spider
Xysticus punctatus is a ground-dwelling crab spider in the family Thomisidae. It is found in the United States and Canada, with records from provinces including Alberta, British Columbia, and Manitoba. As a member of the genus Xysticus, it shares the characteristic crab-like posture and ambush hunting strategy of its relatives.
Xysticus robinsoni
Xysticus robinsoni is a species of ground crab spider in the family Thomisidae, first described by Willis J. Gertsch in 1953. The species belongs to a genus of ambush predators characterized by their crab-like posture and enlarged front legs used to seize prey. Like other Xysticus species, it is likely a sit-and-wait predator that does not construct webs for prey capture. The species occurs in the United States and Mexico, though specific details about its biology remain poorly documented.
Xysticus speciese
Xysticus speciese is a species of crab spider in the family Thomisidae. The genus Xysticus is characterized by ambush hunting behavior and distinctive leg morphology adapted for seizing prey. Members of this genus are typically ground-dwelling and known to overwinter as adults or immatures.
Xysticus triguttatus
Three-banded Crab Spider
Xysticus triguttatus, commonly known as the three-banded crab spider, is a small ambush-hunting spider in the family Thomisidae. The species is widely distributed across North America, with records from the United States and Canada including Alberta, Manitoba, and Saskatchewan. As a member of the genus Xysticus, it exhibits the characteristic crab-like posture and hunting behavior typical of ground crab spiders, lying in wait for prey rather than constructing webs.