Theridiidae
Guides
Anelosimus
cobweb spiders
Anelosimus is a genus of cobweb spiders (Theridiidae) renowned as a model system for studying the evolution of sociality in arachnids. The genus contains approximately 75 species exhibiting the full spectrum of social organization, from solitary to highly social (quasisocial). Eight quasisocial species have been documented, more than any other spider genus. Social species such as Anelosimus eximius form massive communal webs housing tens of thousands of individuals, while solitary species occur at higher altitudes and latitudes. The genus is cosmopolitan, with significant diversity in the Americas, Madagascar, and Australasia.
Anelosimus analyticus
Anelosimus analyticus is a species of cobweb spider in the family Theridiidae. It was described by Chamberlin in 1924. The species is found in the United States and Mexico. It belongs to a genus that includes both solitary and subsocial species, though the social behavior of A. analyticus specifically has not been documented.
Argyrodes elevatus
dew-drop spider, American Dewdrop Spider
Argyrodes elevatus is a kleptoparasitic spider in the family Theridiidae that steals food from the webs of other spiders rather than building its own. Adults measure 4–7 mm in length, with males smaller than females. The species exhibits specialized adaptations for stealth, including vibrational detection of host activity, rapid prey theft completed in under 12 seconds, and nocturnal activity patterns that oppose those of diurnal host species. Courtship involves males presenting silk-wrapped prey as nuptial gifts to females.
Argyrodes nephilae
dewdrop spider
Argyrodes nephilae is a small cobweb spider in the family Theridiidae, commonly known as a dewdrop spider. It lives as a kleptoparasite in the webs of large orb-weaving spiders, particularly those in the genus Nephila. The species ranges from the United States through Central and South America to Argentina and the Galapagos Islands, with introduced populations in India.
Argyrodes pluto
Argyrodes pluto is a species of cobweb spider in the family Theridiidae. It is found in the United States, Mexico, and Jamaica. Like other members of the genus Argyrodes, it is likely a kleptoparasite that lives on the webs of larger orb-weaving spiders, though specific behavioral observations for this species are not documented.
Asagena
Asagena is a genus of cobweb spiders (family Theridiidae) established by Carl Jakob Sundevall in 1833. It comprises nine species distributed across North America, Europe, Asia, and North Africa. Members are small spiders (2.4–5.9 mm body length) that construct webs in sheltered microhabitats including under stones, in leaf litter, under bark, and in moss. The genus was formerly classified within Steatoda.
Asagena americana
Two-spotted Cobweb Spider, Twospotted Cobweb Spider
Asagena americana, commonly known as the two-spotted cobweb spider, is a small theridiid spider native to North America. Males are notably robust with short, muscular legs and possess a stridulating organ used to produce sound during courtship. Females construct cobwebs in concealed microhabitats including under stones, in leaf litter, under bark, and in moss. The species exhibits pronounced sexual dimorphism in body form and is frequently preyed upon by mud dauber wasps.
Asagena fulva
Red-and-white Asagena
Asagena fulva is a small cobweb spider in the family Theridiidae, found in the southwestern United States and Mexico. Females range from 3–5.9 mm in body length, males from 2.4–5 mm. The species appears distinctly redder with more white markings than its congener A. americana. It has been observed in association with harvester ant nests, suggesting possible ant specialization.
Canalidion montanum
Canalidion montanum is a small tangle-web spider (family Theridiidae) and the sole species in the monotypic genus Canalidion. Originally described as Theridion montanum by James Emerton in 1882, it was transferred to its own genus by J. Wunderlich in 2018 based on distinctive cheliceral dentition and male genitalic morphology. The species has a holarctic distribution, occurring across northern North America and Eurasia.
Chrosiothes
Chrosiothes is a genus of comb-footed spiders in the family Theridiidae, established by Eugène Louis Simon in 1894. The genus contains 27 species distributed primarily in the New World, with most species occurring from the United States to Brazil. Males are noticeably smaller than females, with females of C. jamaicensis measuring approximately 2.9 mm compared to 1.6 mm for males. The genus is considered a senior synonym of Theridiotis.
Chrosiothes jenningsi
Chrosiothes jenningsi is a species of cobweb spider in the family Theridiidae. It was described by Piel in 1995. The species is known from the United States. As a member of Theridiidae, it constructs irregular, tangled webs. Very few observations of this species have been documented.
Chrosiothes jocosus
Chrosiothes jocosus is a species of cobweb spider in the family Theridiidae. The species was described by Gertsch & Davis in 1936. It occurs in the United States and Mexico, representing a relatively restricted North American distribution within its genus.
Chrysso
Chrysso is a genus of comb-footed spiders (Theridiidae) first described by Octavius Pickard-Cambridge in 1882. The genus currently contains approximately 64 species distributed primarily in the Americas and Asia, with some species exhibiting wide geographic ranges. Many species display striking and variable coloration, with some capable of rapid color change when disturbed. The genus has undergone recent taxonomic revision, with several former species transferred to the related genera Megama, Meotipa, and Physcoa.
Chrysso albomaculata
Chrysso albomaculata is a species of comb-footed spider in the family Theridiidae, first described by O. Pickard-Cambridge in 1882. The species is documented from the United States, Caribbean islands, and Brazil. It belongs to a genus of small spiders often associated with leaf litter and vegetation in tropical and subtropical habitats. As with many Theridiidae, detailed natural history information remains limited.
Coleosoma
Coleosoma is a genus of comb-footed spiders in the family Theridiidae, established by O. Pickard-Cambridge in 1882. The genus comprises ten currently recognized species with a cosmopolitan distribution. Taxonomic revision has been ongoing, with several species transferred to other genera and numerous synonymies established. The genus includes both native and introduced species, with C. octomaculatum documented as established in New Zealand through anthropogenic introduction.
Coleosoma acutiventer
Coleosoma acutiventer is a species of cobweb spider in the family Theridiidae. It has been recorded across a broad geographic range spanning from the United States through Central America to Argentina. The species was originally described as Achaea acutiventer by Keyserling in 1884. As a theridiid spider, it constructs irregular, tangled webs for prey capture.
Coleosoma floridanum
Coleosoma floridanum is a small cobweb spider in the family Theridiidae. The species has a broad native distribution across the Americas and has been introduced to multiple regions worldwide, including Europe, West Africa, and Pacific islands. It builds irregular, tangled webs characteristic of its family.
Crustulina altera
cobweb spider
Crustulina altera is a small species of cobweb spider in the family Theridiidae, first described by Gertsch and Archer in 1942. It is known from the United States and Jamaica. Like other members of its genus, it constructs irregular, tangled webs typical of theridiid spiders. Very little has been published about the specific biology or ecology of this species.
Crustulina sticta
Brownblack Cobweb Weaver
Crustulina sticta is a small cobweb spider in the family Theridiidae, commonly known as the Brownblack Cobweb Weaver. It has a broad distribution across the Northern Hemisphere, occurring in North America, Europe, and Asia. The species is part of a genus closely related to Steatoda, which includes spiders frequently mistaken for black widows. Available information on its biology is limited compared to better-studied relatives.
Dipoena
tangle-web spiders
Dipoena is a genus of tangle-web spiders (family Theridiidae) containing approximately 162 species distributed worldwide. The genus was established by Tamerlan Thorell in 1869. Males are distinguished by a characteristically high, cylindrical carapace often bearing grooves or depressions on the dorsum, while female carapaces are rarely modified though sometimes elevated. Species occur across Asia, Central America, North America, Africa, the Caribbean, Europe, South America, Australia, and Pacific islands including Vanuatu.
Dipoena dorsata
Dipoena dorsata is a species of cobweb spider in the family Theridiidae, first described by Muma in 1944. It has been recorded across a broad geographic range from the United States to Paraguay, spanning North, Central, and South America. As a member of the genus Dipoena, it constructs irregular, tangled webs typical of theridiid spiders. Specific details regarding its biology, ecology, and behavior remain poorly documented in the scientific literature.
Dipoena malkini
Dipoena malkini is a species of cobweb spider in the family Theridiidae, first described by Levi in 1953. It is a small spider known from the United States. Like other members of the genus Dipoena, it constructs irregular, tangled webs characteristic of theridiid spiders. The species remains poorly documented with limited observational records.
Dipoena washougalia
Dipoena washougalia is a species of cobweb spider in the family Theridiidae, first described by Levi in 1953. It is known from the United States, with records primarily from the Pacific Northwest region. The genus Dipoena comprises small spiders that construct tangled, irregular webs. Information on this particular species remains limited.
Emertonella
Emertonella is a genus of cobweb spiders in the family Theridiidae, subfamily Hadrotarsinae, first described by E. B. Bryant in 1945. The genus was re-delimited in 2024 based on male palpal morphology, transferring approximately 30 species from the genus Euryopis. It now contains species distributed across Africa, Asia, Europe, North and South America, and New Guinea.
spidercobweb-spiderTheridiidaeHadrotarsinaeant-predator-subfamilyre-delimited-genuscosmopolitan-distributionmale-palpal-morphologytaxonomyEuryopis-transferChinaHenan-Provinceforest-habitatagricultural-habitatJuly-collectionelevation-70-1340mBryant-19452024-revisionPMC12964056ZooKeys-1270genus-levelAraneaeArachnidacomb-footed-spiderEnoplognatha intrepida
Enoplognatha intrepida is a cobweb spider in the family Theridiidae, characterized by its membership in the infraorder Araneomorphae. The species has a notably disjunct distribution spanning North America (USA, Canada, Greenland) and East Asia (Korea). It is one of several species in the genus Enoplognatha, which includes the well-studied and polymorphic E. ovata.
Enoplognatha latimana
Scarce candy-striped spider
Enoplognatha latimana is a cobweb spider in the family Theridiidae, described by Hippa & Oksala in 1982. It belongs to a genus noted for polymorphic coloration, though specific appearance details for this species are not well documented. The species has been recorded across a broad Palearctic range and has been introduced to Canada. A 2024 study documented the first known Wolbachia infection in this species, representing supergroup A bacteria in a specimen from north-western Poland.
Enoplognatha marmorata
marbled cobweb spider
A species of cobweb spider in the family Theridiidae, native to the Holarctic region. It constructs tangled, irregular webs in outdoor vegetation rather than in buildings. The species shows considerable color variation, with individuals ranging from pale to dark with marbled or striped abdominal patterns.
Episinus
Square-ended Cobweb Spiders
Episinus is a genus of comb-footed spiders in the family Theridiidae, first described by Walckenaer in 1809. The genus includes approximately 64 described species distributed across Asia, Africa, and the Americas, with 16 species recorded from China. These small spiders are known for their highly reduced, H- or Y-shaped webs constructed near ground level in low vegetation. Several species have conservation significance, including the Tree H-weaver (Episinus maculipes) which is Red Data Book listed in the UK.
Episinus amoenus
cobweb spider
Episinus amoenus is a species of cobweb spider in the family Theridiidae, first described by Banks in 1911. It is found in the United States and Mexico. The species belongs to the genus Episinus, which is characterized by its distinctive web-building behavior and morphology.
Euryopis argentea
Silver Cobweb Weaver
Euryopis argentea is a small cobweb spider in the family Theridiidae, first described by Emerton in 1882. It belongs to the subfamily Hadrotarsinae, a group distinguished by their unique hunting behavior. Unlike typical theridiids that construct tangled prey-catching webs, Euryopis species are active ant predators that use silk in a specialized ambush technique. The species has been recorded from the United States, Canada, and Russia (Kamchatka).
Euryopis californica
Euryopis californica is a small cobweb spider in the family Theridiidae, notable for its highly specialized ant-hunting behavior. Unlike most theridiids that construct tangled webs to capture prey, this species is an active predator that specifically targets harvester ants. It has been documented as a predator of Veromessor pergandei, employing unique hunting tactics to overcome the formidable defenses of these aggressive ants. The species occurs in the United States and Mexico.
Euryopis formosa
Euryopis formosa is a species of cobweb spider in the family Theridiidae, first described by Banks in 1908. It belongs to the genus Euryopis, a group of small ant-hunting spiders that exhibit unusual behavioral traits for their family. The species is found in the United States and Canada. Like other members of its genus, it does not construct prey-catching webs but instead employs active hunting strategies targeting ants.
Euryopis funebris
Euryopis funebris is a small cobweb spider in the family Theridiidae, subfamily Hadrotarsinae. It is native to North America and has been introduced to South Africa. Unlike typical theridiids that build tangled webs, this species is an active ant-hunting specialist that uses silk to immobilize prey rather than construct capture webs.
Euryopis quinquemaculata
Five-spotted ant-hunting spider
Euryopis quinquemaculata is a small cobweb spider in the family Theridiidae, placed in the subfamily Hadrotarsinae. Unlike typical theridiids that construct tangled webs to catch prey, this species is an active ant specialist that hunts without building prey-capturing webs. The species name refers to the five-spotted abdominal pattern characteristic of this and related Euryopis species. It occurs in the United States, where it inhabits areas with high ant activity.
Euryopis tavara
Euryopis tavara is a small cobweb spider in the family Theridiidae, subfamily Hadrotarsinae. Unlike most theridiids, it does not construct prey-catching webs. The species is known from the United States and shares the genus-wide trait of specialized ant predation. It is one of approximately twenty Euryopis species recorded in North America north of Mexico.
Euryopis texana
Euryopis texana is a small cobweb spider in the family Theridiidae, subfamily Hadrotarsinae. It belongs to a genus of ant-specialist predators that hunt without building prey-catching webs. The species occurs in the United States and Mexico. Like other Euryopis, it likely employs a distinctive hunting strategy of ambushing ants and immobilizing them with silk before delivering a venomous bite.
Flexamia huroni
Huron River Leafhopper
Flexamia huroni is a leafhopper species in the family Cicadellidae, described by Bess & Hamilton in 1999. It belongs to the genus Flexamia, a group of leafhoppers known for their specialized host plant associations with grasses. The species is named after the Huron River in Michigan, where it was first collected. Like other members of the genus, it likely exhibits strong ecological dependence on specific grass host plants.
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lobal-biodiversity-information-facilityesbiodiversity-image-portalspanish-collectionstype-specimenlichenantarcticabernensisliyellowstoneHentziectypus globosus
Fingered Cobweaver
Hentziectypus globosus is a species of cobweb spider in the family Theridiidae, commonly known as the Fingered Cobweaver. It is a small spider native to North America. As a member of Theridiidae, it constructs irregular, tangled webs rather than organized orb webs. The species was first described by Nicholas Marcellus Hentz in 1850.
Meotipa pulcherrima
Meotipa pulcherrima is a cobweb spider (family Theridiidae) native to Tropical Africa that has established populations across multiple continents through human-mediated introduction. The species occupies savanna and thicket biomes at moderate elevations and constructs tangled webs in vegetation. It is listed as Least Concern in South Africa due to its broad distribution.
Neopisinus
Neopisinus is a genus of comb-footed spiders in the family Theridiidae, established in 2011 to accommodate species previously placed in other genera. The genus contains nine species distributed across the Americas, from the southern United States through Central America and the Caribbean to South America. Two species, N. fiapo and N. urucu, were described as new in the original genus description. The type species is Neopisinus fiapo.
Neopisinus cognatus
Neopisinus cognatus is a species of cobweb spider (family Theridiidae) described by O. Pickard-Cambridge in 1893. It belongs to a genus of small theridiid spiders found in the Americas. The species has been documented across a broad geographic range spanning from the southern United States through Central America to South America, including the Caribbean region.
Neospintharus
Neospintharus is a genus of comb-footed spiders in the family Theridiidae, subfamily Argyrodinae. First described by Exline in 1950, it was synonymized with Argyrodes in 1962 but revalidated in 2004. Phylogenetic studies confirm it as sister group to Rhomphaea within monophyletic Argyrodinae. The genus comprises free-living species that are not kleptoparasitic, distinguishing them from other Argyrodinae genera.
Neottiura
Neottiura Cobweb Spiders
Neottiura is a genus of comb-footed spiders (family Theridiidae) first described by Anton Menge in 1868. The genus contains six species and one subspecies distributed across Asia, Europe, North America, and North Africa. Members are small cobweb spiders that construct irregular, tangled webs. The type species, Neottiura bimaculata, has the widest distribution, spanning from North America across Eurasia to Japan.
Neottiura bimaculata
Neottiura bimaculata is a species of cobweb spider in the family Theridiidae. It has a broad distribution spanning North America, Europe, Turkey, the Caucasus, Russia (Siberia), Central Asia, China, and Japan. The species was first described by Linnaeus in 1767 under the name Aranea bimaculata. Two subspecies are recognized: N. b. bimaculata and N. b. pellucida.
Nesticodes rufipes
Red House Spider
Nesticodes rufipes, commonly known as the Red House Spider, is a cobweb spider in the family Theridiidae and the sole species in its genus. It has been introduced globally and is found on multiple continents including North America, South America, and oceanic islands. The species has been studied extensively for its predatory behavior, exhibiting a type II functional response to prey density. Research indicates that habitat complexity significantly affects its predation efficiency, with reduced capture rates in more complex environments due to prey refuge availability.
Oxyrrhexis
Oxyrrhexis is a genus of ichneumon wasps in the subfamily Pimplinae, tribe Ephialtini, belonging to the Polysphincta genus-group. The genus comprises four described species worldwide. All species are koinobiont ectoparasitoids specialized in attacking spiders, primarily of the family Theridiidae, though one record documents parasitism of a titanoecid spider. The genus was first recorded from Egypt in 2017.
Parasteatoda tabulata
Wandering House Cobweaver
Parasteatoda tabulata is a cobweb spider in the family Theridiidae, first described by H. W. Levi in 1980. It is native to tropical Asia but has been introduced to North America, Europe, and temperate Asia including China, Korea, and Japan. The species belongs to a genus closely related to the Common House Spider (Parasteatoda tepidariorum) and shares similar web-building habits.
Phoroncidia
Mushroom Comb-footed Spiders, cob-web spiders
Phoroncidia is a genus of comb-footed spiders in the family Theridiidae, first described by J. O. Westwood in 1835. The genus contains approximately 83 species distributed worldwide. Members are characterized by heavily sclerotized, often leathery abdomens with distinctive sculpturing including folds, humps, spines, or tubercles. They are commonly known as Mushroom Comb-footed Spiders.
Phoroncidia americana
Phoroncidia americana is a cobweb spider in the family Theridiidae, first described by Emerton in 1882. It occurs in the United States, Canada, Cuba, and Jamaica. Like other members of its genus, it constructs irregular, three-dimensional cobwebs. The species is part of a genus known for small-bodied spiders with reduced web architecture compared to other theridiids.
Phylloneta
Phylloneta is a small genus of comb-footed spiders (family Theridiidae) containing three species and two subspecies with a Holarctic distribution. The genus was elevated from subgenus status in 2008, having formerly been considered part of Allotheridion. Species include P. impressa, P. pictipes, and P. sisyphia (with subspecies P. s. foliifera and P. s. torandae). The type species, P. pictipes, was originally described in 1884.
Phylloneta pictipes
Phylloneta pictipes is a cobweb spider in the family Theridiidae, native to the United States. This species constructs irregular cobwebs for prey capture. Adults display distinctive coloration with a yellow abdomen bearing patterned black spots, black-banded legs, and a comparatively small cephalothorax. The species has been documented in 1,110 iNaturalist observations, indicating it is moderately well-recorded though not commonly encountered in general natural history.
Platnickina alabamensis
cobweb spider
Platnickina alabamensis is a species of cobweb spider in the family Theridiidae. It was originally described as Theridion alabamense by Gertsch and Archer in 1942. The species is native to North America.
Platnickina mneon
A comb-footed spider in the family Theridiidae, originally described from a female specimen collected in Saga Prefecture, Kyushu, Japan in 1906. The species was recently reinstated as valid based on distinct body coloration, markings, genital morphology, and molecular data (partial mitochondrial COI gene), having been previously synonymized with Yunohamella lyrica. Molecular analysis revealed that females previously identified as Platnickina mneon are conspecific with males associated with Yunohamella varietas, leading to the latter's synonymization. The species is currently classified under the genus Platnickina, though it was transferred to Yunohamella in the revision that reestablished its validity.
Robertus
Robertus is a genus of comb-footed spiders in the family Theridiidae. It was established by Octavius Pickard-Cambridge in 1879 and is recognized as the senior synonym of the former genus Garritus. The genus comprises small spiders that construct tangled, irregular webs. Species within Robertus are found primarily in the Northern Hemisphere, with documented occurrences in Europe and North America.
Robertus frontatus
cobweb spider
Robertus frontatus is a small cobweb spider in the family Theridiidae, first described by Nathan Banks in 1892. The species was originally placed in the genus Microneta before being transferred to Robertus. It is one of many understudied theridiid species with limited published biological information.
Robertus pumilus
Robertus pumilus is a species of cobweb spider in the family Theridiidae. It is found in the United States. The species was described by James Henry Emerton in 1909.
Simitidion
Simitidion is a genus of comb-footed spiders (Theridiidae) described by J. Wunderlich in 1992. The genus contains three recognized species: S. agaricographum, S. lacuna, and S. simile. Native populations occur in Africa, Asia, and Europe, with S. simile introduced to Canada. The genus is part of the diverse cobweb spider family.
Simitidion simile
Simitidion simile is a species of comb-footed spider in the family Theridiidae. Native to the Palearctic region, it has been documented across Europe, North Africa, Turkey, Israel, the Caucasus, Kazakhstan, Iran, and Central Asia. The species has been introduced to Canada, establishing populations outside its native range. As a member of the Theridiidae, it possesses the characteristic comb-like setae on the hind tarsi used for silk handling.
Spintharus
Spintharus is a genus of cobweb spiders (Theridiidae: Argyrodinae) established by Nicholas Marcellus Hentz in 1850. The genus ranges from the northeastern United States to Brazil, with the highest diversity in the Caribbean. A 2018 revision by Agnarsson and colleagues described fifteen new species, many named after celebrities and public figures, making Spintharus notable for having the most species named after celebrities of any spider genus. Molecular evidence indicates that what was historically considered a single widespread species, S. flavidus, actually represents a 30 million year old radiation of at least 16 short-range endemic species in the Caribbean region.
Spintharus flavidus
Spintharus flavidus is a cobweb spider in the family Theridiidae, historically considered a single widespread species ranging from northern North America to Brazil and throughout the Caribbean. Molecular phylogenetic analysis has rejected this hypothesis, revealing instead a 30 million year old radiation of at least 16 distinct species in the Caribbean region alone. Nearly all are short-range endemics with limited overwater dispersal ability. The Caribbean colonization event occurred approximately 30 million years ago, coinciding with the GAARLandia landbridge hypothesis.
Steatoda
False Widow Spiders, Cupboard Spiders
Steatoda is a genus of cobweb spiders in the family Theridiidae containing approximately 120 recognized species with worldwide distribution. Many species are synanthropic, commonly found in human dwellings, sheds, garages, and undisturbed corners. Members are frequently mistaken for widow spiders (Latrodectus) due to similar body shape and web structure, earning them the common name "false widows," though they are significantly less harmful to humans. The genus includes both native and invasive species, with Steatoda nobilis (Noble False Widow) being particularly notable for its rapid range expansion in Europe and North America.
Steatoda albomaculata
white-spotted false widow, white-spotted false widow spider
Steatoda albomaculata is a small cobweb spider in the family Theridiidae, commonly known as the white-spotted false widow. It is widely distributed across North America, Europe, Russia, North Africa, the Middle East, Central Asia, and East Asia. The species has been studied for its predation efficiency on various prey types and is recognized as a generalist predator. It was formerly considered to have two subspecies, but Steatoda albomaculata infuscata was synonymized with the nominate form in 2024, leaving no valid subspecies.
Steatoda castanea
Steatoda castanea is a cobweb spider in the family Theridiidae, closely related to black widows and other Steatoda species. It is native to the Palearctic region, with distribution records from Europe through Russia, the Caucasus, Iran, Central Asia, and China. The species has been introduced to North America, including Canada. As a member of the cobweb weaver family, it constructs irregular tangled webs and shares the general morphology and habits typical of the genus Steatoda, though specific behavioral and ecological details for this species remain poorly documented in available literature.
Steatoda erigoniformis
Steatoda erigoniformis is a cobweb spider in the family Theridiidae. Originally described from the East Mediterranean region, it has a broad native distribution spanning North Africa, the Middle East, Caucasus, and East Asia. The species has been introduced to multiple regions including the United States, Caribbean, Venezuela, Cape Verde, and South Africa, where it has established populations in agricultural and natural habitats. It constructs three-dimensional cobwebs in dark, sheltered locations and has been recorded from sea level to nearly 3,000 meters elevation.
Steatoda grandis
Steatoda grandis is a species of cobweb spider in the family Theridiidae, first described by Banks in 1901. It is known from the United States, though specific details about its biology and ecology remain poorly documented in the scientific literature. The species belongs to a genus that includes several well-known spiders, some of which are frequently encountered in human dwellings.
Steatoda hespera
Steatoda hespera is a species of cobweb spider in the family Theridiidae. It is native to North America and has been documented in the United States and Canada. As a member of the genus Steatoda, it belongs to a group commonly known as false widow spiders, though specific details about its biology and ecology remain limited in the available literature.
Steatoda mexicana
Steatoda mexicana is a cobweb weaver spider (family Theridiidae) described by Herbert W. Levi in 1957. It is native to Mexico and the southwestern United States. Like other Steatoda species, it constructs irregular tangled webs and is a member of the same genus as the well-known Triangulate Cobweb Weaver (S. triangulosa) and the Noble False Widow (S. nobilis). Very little specific information has been published about the biology of this particular species.
Steatoda palomara
Steatoda palomara is a species of cobweb spider in the family Theridiidae. It is known only from the United States, with records from North America. The species was described by Chamberlin & Ivie in 1935. Like other members of the genus Steatoda, it is presumed to construct irregular tangled webs typical of theridiid spiders.
Steatoda variata
Steatoda variata is a species of cobweb spider in the family Theridiidae, first described by Gertsch in 1960. It is found in the United States and Mexico. Two subspecies are recognized: Steatoda variata variata and Steatoda variata china. Very little is known about the specific biology or ecology of this species compared to better-studied congeners like Steatoda triangulosa or Steatoda nobilis.
Steatoda washona
Steatoda washona is a cobweb spider in the family Theridiidae, described by Gertsch in 1960. It belongs to a genus that includes several species commonly known as false widows due to their resemblance to black widows (Latrodectus). The species occurs in the southwestern United States and Mexico. Like other Steatoda species, it constructs irregular tangled webs and is typically found in sheltered microhabitats.
Stemmops
Stemmops is a genus of small comb-footed spiders (Theridiidae: Spintharinae) first described in 1894. The genus contains approximately 27 species, with the majority distributed in the Americas from the United States through Central America to Brazil, and a smaller number of species in East Asia including China, Japan, Korea, and Laos. One species, S. satpudaensis, has been recorded from India.
Stemmops bicolor
Stemmops bicolor is a small spider species in the family Theridiidae (cobweb spiders), first described by O. Pickard-Cambridge in 1894. The species is known from the Caribbean region and parts of Central and North America, with records from Cuba, Mexico, the Bahamas, and the southern United States through Panama. As a member of the genus Stemmops, it belongs to a group of theridiid spiders characterized by their compact body form and specialized web-building behavior.
Theridion
tangle-web spiders
Theridion is a large genus of tangle-web spiders (family Theridiidae) with nearly 600 described species distributed worldwide. The genus has historically served as a wastebasket taxon for theridiid species lacking a colulus that did not fit into other genera. Notable species include T. grallator, the Hawaiian happy face spider, recognized for its distinctive abdominal color patterns, and T. nigroannulatum, one of few spider species known to live in social groups and hunt cooperatively. Molecular studies have revealed that Theridion as traditionally defined is para- or polyphyletic, with Hawaiian representatives representing at least two independent colonization events from different continental sources.
Theridion agrifoliae
Theridion agrifoliae is a species of cobweb spider in the family Theridiidae, described by Levi in 1957. It is native to western North America, with records from the United States and Canada. Like other members of Theridiidae, it constructs irregular, three-dimensional webs to capture prey. The species epithet "agrifoliae" suggests an association with coast live oak (Quercus agrifolia), though specific ecological relationships remain poorly documented.
Theridion albidum
White Long-legged Cobweaver
Theridion albidum is a species of cobweb spider in the family Theridiidae, first described by Banks in 1895. It is native to North America and has been documented in the United States and Canada. As a member of the genus Theridion, it belongs to a large and diverse group of comb-footed spiders that construct irregular, three-dimensional webs. The species is known by the common name "White Long-legged Cobweaver," though detailed natural history information remains limited in published sources.
Theridion arizonense
Theridion arizonense is a species of cobweb weaver spider in the family Theridiidae, described by Herbert W. Levi in 1957. The specific epithet suggests an association with Arizona, though detailed information about this species remains limited in the available literature. As a member of the genus Theridion, it shares the general characteristics of small to medium-sized theridiid spiders that construct irregular, three-dimensional webs.
Theridion australe
Theridion australe is a cobweb spider species in the family Theridiidae, first described by Nathan Banks in 1899. The species is part of the large genus Theridion, which contains numerous small spiders that construct irregular, three-dimensional webs. It has been recorded across parts of the Americas including the United States, Mexico, and Caribbean regions. Like other theridiids, it possesses comb-like spines on the hind tarsi used to manipulate silk.
Theridion californicum
Theridion californicum is a species of cobweb spider in the family Theridiidae. It has been documented in the United States and Canada. As a member of the Theridiidae, it constructs irregular, three-dimensional webs for prey capture.
Theridion cheimatos
Theridion cheimatos is a cobweb spider species in the family Theridiidae. It was described by Gertsch and Archer in 1942. The species is known from the United States, with records from North America. As a member of Theridiidae, it constructs irregular three-dimensional cobwebs and possesses comb-footed spines on the hind legs for manipulating silk.
Theridion differens
Different Cobweb Spider
Theridion differens is a species of cobweb spider in the family Theridiidae. It is found in the United States and Canada, with records from Alberta and British Columbia. The species was described by Emerton in 1882. As a member of the genus Theridion, it constructs the irregular, three-dimensional webs characteristic of this group.
Theridion dilutum
Theridion dilutum is a species of cobweb spider in the family Theridiidae, described by Herbert W. Levi in 1957. It belongs to one of the largest genera of spiders, with members characterized by their irregular, three-dimensional webs. The species occurs in North America, specifically in the United States and Mexico. Like other theridiids, it possesses comb-like serrated bristles on the hind tarsi used to manipulate silk.
Theridion flavonotatum
Theridion flavonotatum is a species of cobweb spider in the family Theridiidae. The species is documented from the United States, Cuba, and Turks & Caicos. Like other members of the genus, it constructs irregular three-dimensional webs. Published information on its biology and ecology remains sparse.
Theridion frondeum
Eastern Long-legged Cobweaver
Theridion frondeum is a species of cobweb spider in the family Theridiidae, commonly known as the Eastern Long-legged Cobweaver. It is found in North America, with records from the United States, Canada, and the Bahama Islands. Like other members of Theridiidae, it constructs irregular three-dimensional webs and possesses comb-like structures on its hind legs for silk handling. The species was first described by Nicholas Marcellus Hentz in 1850.
Theridion goodnightorum
Theridion goodnightorum is a species of cobweb spider in the family Theridiidae, described by arachnologist Herbert W. Levi in 1957. The species epithet honors the husband-and-wife arachnologists Clarence and Marie Goodnight. Like other members of the genus Theridion, this species constructs irregular, three-dimensional cobwebs and possesses the characteristic comb-like bristles (setae) on the hind tarsi used to manipulate silk. The species is documented from the southwestern United States and Mexico.
Theridion kawea
Theridion kawea is a species of cobweb spider described by Herbert W. Levi in 1957. It belongs to the family Theridiidae, a large group of spiders characterized by their irregular, three-dimensional webs and comb-like structures on their hind legs used for silk manipulation. The species has been documented in the southwestern United States and Mexico.
Theridion lawrencei
Theridion lawrencei is a species of cobweb spider in the family Theridiidae, described by Gertsch and Archer in 1942. It is a small theridiid spider found in the United States. Like other members of its family, it constructs irregular, three-dimensional tangled webs. The species is named in honor of someone (likely R.F. Lawrence, a notable arachnologist), though the specific etymology is not documented in available sources. Very little detailed biological information has been published about this species specifically.
Theridion melanurum
Theridion melanurum is a cobweb spider in the family Theridiidae, first described by Hahn in 1831. The species has a broad Palearctic distribution spanning Europe to Siberia, with additional populations in Macaronesia, North Africa, and the Middle East. It has been introduced to the United States, where established populations have been documented. As a member of Theridiidae, it constructs the irregular, three-dimensional webs characteristic of cobweb spiders.
Theridion michelbacheri
Theridion michelbacheri is a species of cobweb spider in the family Theridiidae, first described by Levi in 1957. It is known from the United States, with records indicating presence in North America. As a member of the genus Theridion, it shares the general characteristics of this large and diverse group of comb-footed spiders, though specific details about its biology remain poorly documented.
Theridion morulum
Theridion morulum is a species of cobweb spider in the family Theridiidae, first described by O. Pickard-Cambridge in 1898. It belongs to a large genus of small spiders known for their irregular, three-dimensional webs. The species is recorded from the southwestern United States and Mexico, but detailed biological information appears limited in available sources.
Theridion murarium
Fence Long-legged Cobweaver
Theridion murarium is a species of cobweb spider in the family Theridiidae, first described by Emerton in 1882. It is found in North America, with records from the United States, Canada (including Alberta), and Middle America. Like other Theridiidae, it constructs irregular, three-dimensional webs. The common name 'Fence Long-legged Cobweaver' suggests an association with fence-line habitats, though specific ecological details remain poorly documented.
Theridion neomexicanum
Theridion neomexicanum is a species of cobweb spider in the family Theridiidae. It is found in the United States and Canada. As a member of the Theridiidae, it constructs irregular, three-dimensional webs typical of the family. The species was described by Banks in 1901.
Theridion neshamini
Theridion neshamini is a species of cobweb spider in the family Theridiidae, described by Levi in 1957. The species is known from the United States, though specific details about its biology, habitat preferences, and ecology remain poorly documented. As a member of Theridiidae, it is presumed to construct irregular, three-dimensional cobwebs for prey capture.
Theridion pennsylvanicum
Theridion pennsylvanicum is a cobweb spider in the family Theridiidae, described by Emerton in 1913. It belongs to the infraorder Araneomorphae, the true spiders. The species is known from the United States and Canada. Like other members of Theridiidae, it constructs irregular, three-dimensional webs and possesses the comb-like spines on the hind legs characteristic of this family.
Theridion petraeum
Theridion petraeum is a cobweb spider in the family Theridiidae, described by L. Koch in 1872. The species has a broad distribution spanning North America, Europe, North Africa, the Caucasus, and Russia extending to the Far East and Kazakhstan. Records indicate presence across multiple continents including Africa and northern Asia. As a member of Theridiidae, it constructs irregular three-dimensional webs, though specific details of its biology and ecology remain poorly documented in available sources.
Theridion pictum
Painted Cobweb Weaver
Theridion pictum is a cobweb spider in the family Theridiidae and the type species of the genus Theridion. It has a Holarctic distribution spanning North America, Europe, and Asia, with introduced populations in South Africa. The species constructs three-dimensional webs in damp, low-lying areas, often on vegetation or man-made structures. Adults mature in early to mid-summer, with females persisting into autumn.
Theridion pierre
Theridion pierre is a species of cobweb spider in the family Theridiidae, described by Levi & Patrick in 2013. It is a member of the large genus Theridion, which contains numerous small spiders that construct irregular, three-dimensional webs. The species is known from the United States.
Theridion rabuni
Theridion rabuni is a species of cobweb spider in the family Theridiidae. It is known from the United States and the Bahama Islands. Little specific information is available about its biology, ecology, or behavior beyond its taxonomic placement and geographic distribution.
Theridion submissum
Theridion submissum is a species of cobweb spider in the family Theridiidae. The species was described by Gertsch and Davis in 1936. It is found in the United States, Mexico, the Bahama Islands, and Jamaica. Like other members of the genus Theridion, it constructs irregular three-dimensional webs.
Theridion transgressum
Theridion transgressum is a species of cobweb spider in the family Theridiidae, first described by Petrunkevitch in 1911. It belongs to the large genus Theridion, which contains numerous small-bodied spiders that construct irregular, three-dimensional webs. The species is recorded from the United States and Mexico. Very little specific biological information is available for this species.
Theridion varians
Variable Cobweb Spider
Theridion varians is a species of cobweb spider in the family Theridiidae. It has a broad native distribution spanning Europe, North Africa, Turkey, the Caucasus, Russia, Central Asia, and China. The species has been introduced to North America, where it is now established in Canada and the United States. Four subspecies are recognized, reflecting geographic variation across its range.
Theridula gonygaster
Ladybird Spider
Theridula gonygaster is a species of cobweb spider in the family Theridiidae. Commonly known as the Ladybird Spider, it has a broad native range across Central and South America and the Caribbean, and has been introduced to multiple regions including parts of Europe, Africa, and Asia. The species is notable for its widespread anthropogenic dispersal and distinctive appearance.
Thymoites camano
cobweb spider
Thymoites camano is a species of cobweb spider in the family Theridiidae, first described by Levi in 1957. It is known only from the United States. As a member of Theridiidae, it constructs irregular, three-dimensional webs to capture prey. The species remains poorly documented in scientific literature.
Thymoites minero
Thymoites minero is a species of cobweb spider in the family Theridiidae, first described by Vincent D. Roth in 1992. The species is known from the United States and is part of a genus of small theridiid spiders. Like other members of Theridiidae, it constructs irregular, three-dimensional webs rather than the flat orb webs characteristic of many other spider families. The genus Thymoites contains numerous species, many of which are poorly known and difficult to distinguish without close examination.
Thymoites pallidus
Thymoites pallidus is a species of comb-footed spider in the family Theridiidae, first described by Emerton in 1913. This species is known from Cuba, the United States, and the Caribbean region extending to Venezuela. Like other theridiid spiders, it possesses the characteristic comb-like serrated bristles (setae) on the tarsi of the hind legs used for manipulating silk. The species epithet 'pallidus' refers to its pale coloration.
Tidarren sisyphoides
Tent Cobweb Weaver
Tidarren sisyphoides is a tangle web spider (family Theridiidae) known for extreme sexual size dimorphism, with males approximately 10% the size of females. The species exhibits a rare mating system in which males die during copulation and remain attached to females for over two hours, though females do not practice sexual cannibalism. It constructs a distinctive three-dimensional web with a dome-shaped sheet and upper tangle that functions as the primary prey capture structure.
Wamba crispulus
Wamba crispulus is a species of cobweb spider in the family Theridiidae, originally described as Theridion crispulum by Eugène Simon in 1895. The species has an exceptionally broad distribution spanning the Americas from Canada to Brazil and throughout the Caribbean. It belongs to the genus Wamba, which contains relatively few described species.
Yunohamella
Yunohamella is a genus of comb-footed spiders in the family Theridiidae, established by H. Yoshida in 2007. The genus is characterized by distinct male genital morphology: a large tegulum, small median apophysis, thin embolus, and distinct tegular apophysis. Females have an epigyne lacking a pointed scapus or possessing a blunt scapus. As of 2026, the genus comprises thirteen species distributed across Asia, Europe, and North America. Recent taxonomic revisions have clarified species boundaries using morphological and molecular data, including the reestablishment of Y. mneon as a valid species and the synonymy of Y. varietas.
Yunohamella lyrica
Lyric Cobweaver
Yunohamella lyrica is a cobweb spider in the family Theridiidae, commonly known as the Lyric Cobweaver. The species has a broad geographic distribution spanning North America and East Asia, including Korea and Japan. It belongs to a genus of small spiders that construct irregular, tangled webs.