Ground-dwelling
Guides
Pagasa pallipes
Pagasa pallipes is a small predatory true bug in the family Nabidae (damsel bugs), subfamily Prostemmatinae. The species was described by Stål in 1873 and has been recorded from Mexico and parts of North America. Members of the genus Pagasa are ground-dwelling predators with somewhat beetle-like appearance.
Paranthaclisis hageni
Hagen's antlion
Paranthaclisis hageni is a species of antlion (Neuroptera: Myrmeleontidae) originally described by Banks in 1899 as Acanthaclisis hageni. The species is native to North and Middle America, with documented presence in both regions. As a member of the antlion family, it shares the characteristic life history of having predatory larvae that construct pit traps in sandy substrates to capture prey, and aerial adults that are typically nocturnal and weak fliers.
Pardosa
Thin-legged Wolf Spiders
Pardosa is a large genus of wolf spiders comprising over 500 described species with worldwide distribution except Australia. These spiders are generally small to medium-sized (3–12 mm body length), characterized by long, thin legs with prominent perpendicular spines. They occupy diverse habitats including wetlands, woodlands, grasslands, and high-elevation environments. Many species exhibit sexual dimorphism in coloration, with mature males often displaying distinct patterns from females. Species identification requires microscopic examination of genitalia.
Pardosa albomaculata
Thin-legged wolf spider
Pardosa albomaculata is a species of thin-legged wolf spider in the family Lycosidae, originally described by Emerton in 1885. It was previously treated as a synonym of P. groenlandica but has been reestablished as a distinct species based on morphological differences in male palpal structures and female epigynes. It belongs to the glacialis/groenlandica species complex, a group of closely related Holarctic Pardosa species. The species is part of the most abundant genus of wolf spiders in North America.
Pardosa atlantica
Atlantic wolf spider, thin-legged wolf spider
Pardosa atlantica is a species of wolf spider in the family Lycosidae, described by Emerton in 1913. As a member of the genus Pardosa, commonly known as thin-legged wolf spiders, it belongs to one of the most abundant wolf spider genera in North America. The species is found in the United States, though specific details about its ecology and biology remain limited in available literature. Like other Pardosa species, it is likely a ground-dwelling, active hunter.
Pardosa fuscula
Pardosa fuscula is a small to medium-sized wolf spider in the family Lycosidae, distributed across the United States and Canada. As a member of the thin-legged wolf spider genus Pardosa, it exhibits characteristic long leg spines and elevated cephalothorax typical of the group. The species occupies diverse habitats including wetlands, woodlands, and open fields. Identification to species level requires microscopic examination of genitalia.
Pardosa lowriei
Lowrie's Thin-legged Wolf Spider
Pardosa lowriei is a species of thin-legged wolf spider in the family Lycosidae, first described by Kronestedt in 1975. As a member of the genus Pardosa, it is characterized by long spines on the legs that are nearly perpendicular to the leg axis, distinguishing it from other wolf spider genera. The species is found in the United States and Canada. Like other Pardosa species, it is likely a ground-dwelling active hunter, though specific behavioral details for this species are not well documented.
Pardosa mercurialis
Pardosa mercurialis is a species of thin-legged wolf spider in the family Lycosidae, found in the United States. It belongs to the genus Pardosa, which comprises small to medium-sized wolf spiders characterized by long, perpendicular leg spines. Species-level identification requires microscopic examination of genitalia. Like other Pardosa species, it is likely ground-dwelling and associated with varied terrestrial habitats, though specific ecological details for this species remain poorly documented.
Pardosa metlakatla
thin-legged wolf spider
Pardosa metlakatla is a species of thin-legged wolf spider in the family Lycosidae, first described by Emerton in 1917. As a member of the genus Pardosa, it belongs to one of the most abundant and widespread wolf spider genera in North America. The species occurs in the United States and Canada, with confirmed records from Alberta and British Columbia. Like other Pardosa species, it is characterized by long, perpendicular leg spines and a preference for moist habitats near water.
Pardosa moesta
Shiny Wolf Spider
Pardosa moesta is a small to medium-sized wolf spider (family Lycosidae) belonging to the 'moesta species group' in the Nearctic region. It is one of the most abundant wolf spiders in North American grasslands, characterized by its 'thin-legged' morphology with long spines nearly perpendicular to the leg axis. The species has an annual life cycle with overwintering as subadults, and exhibits maternal care through egg sac transport. It serves as host for parasitoid wasps including Baeus sp. (Scelionidae) and Gelis sp. (Ichneumonidae), with documented egg sac parasitism rates around 14.6%.
Pardosa pauxilla
thin-legged wolf spider
Pardosa pauxilla is a small wolf spider in the family Lycosidae, first described by Montgomery in 1904. It belongs to the genus Pardosa, commonly known as thin-legged wolf spiders, characterized by distinctive long leg spines perpendicular to the leg axis. The species is documented from the United States, with 626 observations recorded on iNaturalist. Like other Pardosa species, it likely inhabits diverse environments including wetlands, woodlands, and open fields.
Pardosa uintana
Pardosa uintana is a species of thin-legged wolf spider in the family Lycosidae, described by Gertsch in 1933. Like other members of the genus Pardosa, it is characterized by long spines on the legs that are nearly perpendicular to the leg axis. The species occurs in western North America, with records from Alberta and British Columbia in Canada. As with most Pardosa species, identification to species level requires microscopic examination of genitalia.
Peritaxia
Peritaxia is a genus of broad-nosed weevils (Curculionidae: Entiminae) established by Horn in 1876. The genus contains approximately seven described species distributed in western North America. Species are characterized by their relatively small size and distinctive sculpturing of the elytra and pronotum. The genus is classified in the tribe Byrsopagini, a group of flightless weevils associated with particular soil and vegetation conditions.
Philolithus actuosus
Philolithus actuosus is a species of darkling beetle in the family Tenebrionidae, described by Horn in 1870. It belongs to a genus of robust, ground-dwelling beetles found in arid and semi-arid regions of North America. Like other Philolithus species, it exhibits the characteristic tank-like body form typical of many desert tenebrionids, adapted for life in exposed, often sandy or rocky habitats. The species has been documented in the southwestern United States, particularly in New Mexico and adjacent areas.
Phrurolithidae
Guardstone Spiders
Phrurolithidae is a family of araneomorph spiders commonly known as guardstone spiders. First described by Nathan Banks in 1892, the family was long treated as a subfamily (Phrurolithinae) within Corinnidae until phylogenetic studies established its separate family status. The family currently comprises 27 genera and approximately 421 species. Members are small to medium-sized spiders, predominantly found in the Northern Hemisphere with exceptional diversity in southern China, where many species are endemic to specific mountain localities.
Pimeliinae
Pimeliinae is a subfamily of darkling beetles (Tenebrionidae) comprising multiple tribes distributed across arid and semi-arid regions worldwide. The subfamily includes notable groups such as the Sepidiini of the Afrotropical Realm, whose members Ocnodes and Psammodes are known as "toktokkies" for their distinctive tapping communication behavior. Several genera exhibit morphological adaptations for fossorial life, including conical peg sensilla on tibiae. The subfamily encompasses both flightless and flying species, with some of the largest tenebrionid species such as Stridulomus sulcicollis (~80 mm).
Prostemmatini
Prostemmatini is a tribe of damsel bugs within the family Nabidae, order Hemiptera. Members are predatory true bugs characterized by their raptorial forelegs adapted for catching prey. The tribe is distinguished from the other nabid tribe, Nabini, by specific morphological features of the male genitalia and wing venation. These insects are generally found in ground-level vegetation and leaf litter where they hunt small arthropods.
Purealus
Purealus is a monotypic genus of cleonine weevils (Curculionidae: Lixinae: Cleonini) endemic to the southwestern United States. The genus was erected to accommodate Purealus beckelorum, a species that cannot be placed in existing North American genera Apleurus or Scaphomorphus due to a unique combination of morphological characters. The genus is distinguished by two autapomorphies within Cleonini: a distinctly tumescent and asperate base of elytral interval 3, and widely separated procoxae. The single known species is winter-active and ground-dwelling in arid environments.
Purealus beckelorum
A recently described cleonine weevil endemic to the southern High Plains, representing the type species of its monotypic genus. Distinguished from all other world Cleonini by two unique character states: widely separated procoxae and a distinctly tumescent, asperate base of elytral interval 3. A moderately robust, wingless species with body length 7.8–9.4 mm. Known from only nine specimens despite targeted collecting efforts.
Rabidosa
Rabid Wolf Spiders, Dotted Wolf Spiders
Rabidosa is a genus of wolf spiders (family Lycosidae) established by Roewer in 1960. The genus contains five recognized species distributed in North America, with most species restricted to the United States. These are medium to large-sized, ground-dwelling spiders with characteristic patterning on the dorsal abdomen. Members of this genus have been subjects of behavioral research, particularly regarding mating systems and thermal ecology. Several species are known hosts for parasitic mantisfly larvae.
Rabidosa santrita
Santa Rita Wolf Spider
Rabidosa santrita is a species of wolf spider in the family Lycosidae, found in the United States and Mexico. It is a known host for the spider wasp Anoplius aethiops, which paralyzes and provisions it as food for its larvae. The species belongs to a genus of large, ground-dwelling wolf spiders that exhibit maternal care by carrying egg sacs and spiderlings.
Scantius aegyptius
Mediterranean red bug
Scantius aegyptius, commonly known as the Mediterranean red bug, is a ground-dwelling true bug in the family Pyrrhocoridae. It is recognized by its striking red and black aposematic coloration. The species is native to the Mediterranean region and has established invasive populations in North America, particularly in California since 2009. It feeds primarily on seeds and seed pods of plants in the family Malvaceae.
Schizocosa
Brush-legged Spiders
Schizocosa is a genus of wolf spiders (Lycosidae) comprising 56 species distributed across North and South America, Africa, and East and Southeast Asia. Members are medium to large spiders (5–15 mm, occasionally to 28 mm) with strong legs, keen eyesight, and distinctive carapace morphology. The genus is notable for elaborate male courtship behaviors involving vibratory and acoustic signals, with some species exhibiting prominent leg ornamentation. Several species have been extensively studied for sexual selection, reproductive isolation, and behavioral ecology.
Schizocosa avida
lance wolf spider
Schizocosa avida is a species of wolf spider (family Lycosidae) native to North America. It is one of the most frequently observed Schizocosa species, with substantial iNaturalist documentation. The species is known to serve as a host for the parasitic mantidfly Climaciella brunnea, whose larvae board female spiders and consume their egg sac contents. Like other wolf spiders, it is a ground-dwelling active hunter.
Schizocosa mimula
A wolf spider in the family Lycosidae, Schizocosa mimula is a ground-dwelling species found in Mexico and the southwestern United States. Like other members of its genus, it likely exhibits typical lycosid behaviors including active hunting without webs and maternal care of egg sacs. The species was described by Gertsch in 1934 and remains poorly documented in scientific literature.
Schizocosa minnesotensis
Schizocosa minnesotensis is a wolf spider species in the family Lycosidae. It occurs in the United States and Canada, with confirmed records from Alberta and British Columbia. As a member of the genus Schizocosa, it is a ground-dwelling active hunter. The species has been documented as a host for the mantidfly Climaciella brunnea, whose larvae board female spiders and feed on their egg sac contents.
Schizocosa retrorsa
Schizocosa retrorsa is a wolf spider species in the family Lycosidae, found in the United States and Mexico. As a member of the genus Schizocosa, it shares characteristics with other wolf spiders including ground-dwelling habits and active hunting behavior. The species has been recorded as a host for the mantidfly Climaciella brunnea, whose larvae parasitize spider egg sacs.
Schizocosa saltatrix
Schizocosa saltatrix is a species of wolf spider in the family Lycosidae, first described by Hentz in 1844. It occurs in North America and shares the characteristic traits of its genus, including ground-dwelling habits and active hunting behavior. The species has been documented as a host for parasitic mantidfly larvae, specifically Climaciella brunnea.
Scotinella
Scotinella is a genus of small araneomorph spiders in the family Phrurolithidae, first described by Nathan Banks in 1911. The genus contains 24 described species distributed across North America, with the highest diversity in the United States and Mexico. Species range from the type species Scotinella pallida in the eastern United States to numerous Mexican endemics. These spiders are ground-dwelling hunters with limited published ecological data.
Scotinella fratrella
Scotinella fratrella is a small true spider in the family Phrurolithidae, described by Gertsch in 1935. The species occurs in North America, with records from the United States and Canada. It belongs to a genus of ground-dwelling spiders that are generally associated with leaf litter and soil habitats. Very few observations of this species have been documented, reflecting either genuine rarity or cryptic habits.
Scotinella minnetonka
Scotinella minnetonka is a small true spider in the family Phrurolithidae, a group of ground-dwelling spiders often associated with leaf litter and soil habitats. The species was described in 1930 and is known from scattered records across the United States and Canada. Like other phrurolithids, it likely exhibits secretive habits and may be undercollected due to its small size and cryptic lifestyle.
Scotinella redempta
Scotinella redempta is a small ground-dwelling spider in the family Phrurolithidae, native to eastern North America. It measures approximately 2.1–2.4 mm in body length and inhabits deciduous forest leaf litter. The species was originally misidentified in 1930 and formally described by Willis J. Gertsch in 1941.
Sirthenea
corsairs
Sirthenea is a cosmopolitan genus of assassin bugs (Reduviidae: Peiratinae) comprising at least 40 described species. It is distinguished from other Peiratinae by an elongated body, triangular anteocular head, shortened rounded femora, and the absence of fossa spongiosa on medial tibiae (except in S. laevicollis). The genus has a nearly global distribution spanning Afrotropical, Oriental, Palearctic, Oceanian, and Australian regions, with representatives occurring on almost all continents. Sirthenea species are ground-dwelling, nocturnal predators that prey on other insects.
Socalchemmis miramar
false wolf spider, wandering spider
Socalchemmis miramar is a species of spider in the family Zoropsidae, described by Platnick and Ubick in 2001. It belongs to a group commonly referred to as false wolf spiders or wandering spiders. The species is known from the United States, with records indicating a distribution in southern California. As a member of Zoropsidae, it represents part of a family of spiders that are generally ground-dwelling and nocturnal hunters.
Steiroxys trilineatus
Three-lined Shieldback, Three-lined Camel Cricket
Steiroxys trilineatus is a shieldback katydid native to western North America, recognized by the three pale longitudinal stripes running along its dorsal surface. This flightless, ground-dwelling species inhabits grassland and sagebrush steppe ecosystems, where it occupies a cryptic lifestyle among vegetation and litter. Adults are active during summer months, with males producing songs via tegminal stridulation to attract mates. The species has been documented from the Great Basin through the Rocky Mountain region, with populations adapted to semi-arid conditions.
Stemonyphantes
Stemonyphantes is a genus of sheet-weaving spiders in the family Linyphiidae, first described by Anton Menge in 1866. The genus comprises approximately 20 species distributed across the Palearctic region, with some species extending into North America. As members of Linyphiidae, they construct flat, horizontal sheet webs for prey capture. The type species, Stemonyphantes lineatus (Linnaeus, 1758), is widespread across Europe and into Central Asia.
Stenomorpha rimata
Stenomorpha rimata is a species of darkling beetle in the family Tenebrionidae, tribe Asidini. The genus Stenomorpha is large and taxonomically complex, historically containing 88 species with limited modern revision until recent work by Fran Keller and colleagues. S. rimata was described by LeConte in 1854. Species in this genus occur in arid and semi-arid regions of western North America and Mexico, with some flightless species restricted to specific mountain ranges.
Syspira
prowling spiders
Syspira is a genus of prowling spiders in the family Miturgidae, first described by Simon in 1895. These active, nocturnal hunters are characterized by their leggy appearance and body lengths of 10–18 mm. The genus occurs in arid and semi-arid regions of the southwestern United States, Mexico, and the Caribbean, with highest diversity in western North America. Taxonomic revision is ongoing, with species historically placed in Clubionidae and some specimens of S. pallida potentially belonging to the unrelated genus Zorocrates.
Talavera minuta
Minute Jumping Spider
Talavera minuta is a small jumping spider in the family Salticidae. It is one of the smallest members of its genus, with an adult body length of approximately 2-3 mm. The species has a transcontinental distribution spanning eastern Russia and North America. Like other salticids, it possesses excellent vision and active hunting behavior, though specific ecological details remain poorly documented.
Teleasinae
Teleasinae is a subfamily of minute parasitoid wasps in the family Scelionidae. Members are exclusively egg parasitoids of ground beetles (Carabidae), making them unique among Scelionidae in this host specialization. The subfamily contains approximately 14 genera and over 480 described species worldwide, with Trimorus alone comprising 389 species. Taxonomic placement has shifted historically, having been treated previously as a subfamily of Platygastridae before molecular analyses reclassified Scelionidae as a subfamily within Platygastridae.
Teminius
Teminius is a genus of spiders in the family Miturgidae, first described by Keyserling in 1887. The genus contains four recognized species distributed across the Americas, from the United States through Central America and the Caribbean to Argentina. Teminius species are long-legged wandering spiders that do not build permanent webs for prey capture.
Tenuiphantes tenuis
A minute sheet-web spider native to Europe, Macaronesia, Northern Africa, Turkey, the Caucasus, and Central Asia. It has been introduced to the USA, Chile, Argentina, and New Zealand. Adults measure 2–3 mm in body length and are characterized by a dark brown carapace, brown legs without annulations, and a slender abdomen often bearing distinctive black spots. The species inhabits low vegetation, moss, and leaf litter.
Thanatus
false crab spiders, running crab spiders
A genus of running crab spiders (family Philodromidae) described by C.L. Koch in 1837. Adults reach 5–6 mm in body length and are primarily ground-dwelling hunters found on low vegetation and open surfaces. The genus is distinguished from similar Philodromus by eye arrangement differences and is characterized by a prominent leaf-like cardiac mark on the anterior dorsal abdomen. Thanatus species overwinter as adults and are among the most abundant active spiders in early spring in temperate regions.
Thanatus altimontis
Thanatus altimontis is a running crab spider in the family Philodromidae, first described by Gertsch in 1933. As a member of the genus Thanatus, it shares the characteristic ground-dwelling hunting behavior typical of this group, contrasting with the vegetation-dwelling habits of related slender crab spiders (Tibellus). The species occurs in mountainous regions of western North America, with records from the western United States, Mexico, and western Canadian provinces. Like other Thanatus species, it likely overwinters as an adult and becomes active in early spring, when specimens have been observed basking on warm surfaces.
Thanatus formicinus
Running Crab Spider, Ant-mimic Crab Spider
Thanatus formicinus is a running crab spider in the family Philodromidae with a Holarctic distribution spanning North America, Europe, and Asia. It is a ground-dwelling hunter active during spring and early summer, often observed basking on warm surfaces like concrete paths. The species exhibits ant-mimicry in both appearance and behavior, a distinctive trait among crab spiders.
Thanatus striatus
Striped Running Crab Spider
Thanatus striatus is a running crab spider in the family Philodromidae, characterized by its striped cephalothorax and ground-dwelling hunting behavior. The species has a broad distribution across the Northern Hemisphere, including North America, Europe, Turkey, Russia, and Central Asia. It is active primarily in spring and early summer, with adults capable of overwintering. The species is distinguished from similar slender crab spiders by its more robust body form and preference for ground-level habitats.
Thanatus vulgaris
Cricket Thief Spider
Thanatus vulgaris is a running crab spider in the family Philodromidae with a remarkably wide global distribution spanning native Palearctic ranges and introduced populations across multiple continents. The species occupies diverse terrestrial habitats from natural grasslands and shrublands to agricultural systems. It is known for ground-dwelling behavior and has been observed engaging in ballooning dispersal. Two subspecies are recognized: T. v. vulgaris and T. v. creticus.
Tigrosa grandis
Tigrosa grandis is a species of wolf spider in the family Lycosidae, endemic to the United States. The species was originally described by Nathan Banks in 1894. It occurs across a broad central swath of the country, from the northern plains south to Texas. As a member of the wolf spider family, it is an active ground-dwelling hunter that does not build webs to capture prey.
Trachelidae
Broad-Faced Sac Spiders, Ground Sac Spiders
Trachelidae is a family of araneomorph spiders within the RTA clade, elevated from subfamily status in 2014 based on molecular phylogenetic evidence. The family comprises 29 genera and approximately 307 species distributed across tropical, subtropical, and temperate regions worldwide. Members are commonly known as broad-faced sac spiders or ground sac spiders, though many species are arboreal. The family is characterized by reduced leg spines and other distinctive morphological synapomorphies that distinguish it from related families Corinnidae and Clubionidae.
Trochosa
Trochosa is a large genus of wolf spiders (Lycosidae) with worldwide distribution. These medium-sized, ground-dwelling spiders are cursorial hunters that do not construct webs to capture prey. The genus is particularly well-documented in Europe and North America, though it remains taxonomically unrevised in Africa. As of October 2025, the genus contains 93 species.