marsh fly
Sepedon armipes is a North American species of marsh fly in the family Sciomyzidae, commonly known as snail-killing flies. Like other members of its genus, its larvae are aquatic predators of pulmonate snails. The species exhibits early-season activity, with adults observed active as early as February.
Florida snail-killing fly
A species of snail-killing marsh fly in the family Sciomyzidae, endemic to Florida. Adults are active in early spring and are associated with aquatic habitats where their predatory larvae feed on pulmonate snails. The species was described by Steyskal in 1951 and belongs to a genus with 20 recognized species in North America, many of which have been investigated for potential biological control of snail vectors of parasitic diseases.
marsh fly
Sepedon fuscipennis is a species of marsh fly in the family Sciomyzidae. The larvae are aquatic predators of pulmonate snails, living just beneath the water surface suspended by water-resistant hairs surrounding their posterior spiracles. Adults are slender flies with a concave face and jutting antennae; males have distinctive bowed hind tibiae and swollen, toothed hind femora for grasping females during mating. The species exhibits overlapping generations during summer with unimodal population peaks, and has been studied for its potential in biological control of snail hosts of parasitic diseases.
snail-killing fly
Sepedon gracilicornis is a species of snail-killing fly in the family Sciomyzidae, described by Orth in 1986. It belongs to a genus of approximately twenty North American species whose larvae are obligate predators of aquatic pulmonate snails. The species has been documented through limited observations, with records indicating presence in wetland and aquatic edge habitats.
Alderfly
Sialis rotunda is a species of alderfly in the family Sialidae, order Megaloptera. It is a small to medium-sized aquatic insect whose larvae develop in freshwater habitats. Adults are short-lived and primarily focus on reproduction. The species was described by Nathan Banks in 1920 and is native to western North America.
Silis is a genus of soldier beetles in the family Cantharidae, established by Charpentier in 1825. The genus contains at least 80 described species distributed across the Northern Hemisphere, with records from Colombia, Denmark, and Norway. Soldier beetles in this genus are soft-bodied, elongated beetles with flexible elytra. They are active predators or pollen feeders as adults.
Sinea complexa is a species of assassin bug in the family Reduviidae, first described by Caudell in 1900. It was long confused with the eastern species Sinea incognita, which was described as new in 2015 based on morphological differences in the front leg femora. The species occurs in western and southwestern North America and Mexico. Like other Sinea species, it is a predatory insect that likely feeds on other arthropods.
Spined Assassin Bug
Sinea diadema is a North American assassin bug in the family Reduviidae, commonly known as the spined assassin bug. The species exhibits bivoltine life history, with adults active primarily in late summer and autumn. It is an active predator of small insects, often associated with flowering plants in open habitats. The species overwinters in the egg stage.
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.
solifuges, camel spiders, sun spiders, wind scorpions, solpugids
Solifugae is an order of arachnids comprising over 1,200 described species in approximately 147 genera and 16 families. These animals are neither true spiders nor scorpions, though they share superficial similarities with both. They are characterized by exceptional speed, large powerful chelicerae used for predation and stridulation, and a preference for arid habitats. The order is divided into two suborders: Australosolifugae (predominantly Southern Hemisphere) and Boreosolifugae (predominantly Northern Hemisphere).
Sosylus is a genus of dry bark beetles in the family Bothrideridae, containing approximately eight described species. These beetles are significant natural predators and parasites of ambrosia beetles (family Platypodidae). The genus has been documented in New Guinea and other regions, with species exhibiting distinctive triungulin-type first-instar larvae—a mobile larval form rare among beetles.
Two-ridged False Snail-eating Beetle
Sphaeroderus bicarinatus is a ground beetle in the family Carabidae, commonly known as the two-ridged false snail-eating beetle. It is a brachypterous, mostly nocturnal predator found in forested habitats of the southeastern United States. Despite its common name, it has been observed preying on snails as well as Lepidoptera caterpillars and pupae.
Black-striped Globetail
Sphaerophoria novaeangliae is a species of syrphid fly, commonly known as the Black-striped Globetail. It belongs to a genus whose members are frequently observed hovering near flowers and are often mistaken for bees or wasps due to their yellow and black coloration. The species was described by Johnson in 1916. As with other Sphaerophoria species, adults are pollinators that visit flowers for nectar and pollen.
thread-waisted wasp
Sphex ashmeadi is a species of thread-waisted wasp in the family Sphecidae. It has been observed in New Mexico, USA, where it visits milkweed flowers. The species is part of the diverse Sphex genus, which includes solitary wasps that excavate burrows and provision them with paralyzed prey for their larvae.
mantis shrimp, spearer mantis shrimp
Squilla is a genus of stomatopod crustaceans commonly known as mantis shrimp or spearer mantis shrimp. Members of this genus are small marine predators, typically 40–70 mm in length, characterized by raptorial appendages adapted for spearing soft-bodied prey rather than smashing hard shells. The genus has a fossil record dating to 145 million years ago and has diversified into over a dozen extant species. Squilla species are distributed in tropical and subtropical marine waters worldwide, including the Indian Ocean and Mediterranean Sea.
Carolina mantis, Carolina mantid
Stagmomantis carolina, the Carolina mantis, is a native North American mantid species ranging from New Jersey south to Florida and west to Arizona. It is smaller than introduced mantid species such as the Chinese mantis (Tenodera sinensis) and European mantis (Mantis religiosa), typically exhibiting gray or brown coloration. The species overwinters as eggs in protective cases called oothecae, with nymphs emerging in spring and adults present from July through October. It serves as an important predator in gardens and natural landscapes, with documented parasitism by the tachinid fly Masiphya confusa.
Larger Florida Mantis
Stagmomantis floridensis, commonly known as the larger Florida mantis, is a native species of praying mantis found in the southeastern United States. It belongs to the genus Stagmomantis, which includes several other North American mantis species. As a member of the Mantidae family, it shares the characteristic predatory adaptations of mantids, including raptorial forelegs for capturing prey. The species was described by Davis in 1919 and is distinguished from other regional mantids by its larger size and geographic distribution centered on Florida and surrounding states.
Stagmomantis resacae is a species of mantis described in 2021, making it a relatively recent addition to the genus Stagmomantis. It is native to North America. As a member of the Mantidae family, it shares the characteristic predatory morphology and behaviors typical of mantids, including raptorial forelegs adapted for catching prey. The species name suggests a possible association with resaca habitats—oxbow lakes or seasonal wetlands common in the southern United States and northern Mexico.
Cupboard spider, Dark comb-footed spider, Brown house spider, False black widow
Steatoda grossa is a cosmopolitan cobweb spider in the family Theridiidae, native to Europe and temperate Asia and introduced globally. It constructs irregular three-dimensional webs in dark, sheltered locations and is frequently mistaken for venomous black widows (Latrodectus spp.) due to its similar body shape and coloration, though it lacks the distinctive red hourglass marking. Bites to humans are rare and generally minor, causing localized pain and blistering with occasional systemic symptoms.
Steniolia eremica is a species of sand wasp in the family Crabronidae, described by James E. Gillaspy in 1964. It is one of approximately fifteen species in the genus Steniolia, all of which are restricted to western North America. Males are larger than females and have been observed visiting thistle flowers and other nectar sources. The species is considered less abundant than congeners that share its range.
Stenodynerus fundatiformis gonosceles is a subspecies of mason wasp in the subfamily Eumeninae. The genus Stenodynerus contains solitary, cavity-nesting wasps provisioned with paralyzed caterpillars. This subspecies is poorly documented in available sources, with only one observation recorded on iNaturalist. Males of the genus have a distinctive antennal modification: the last antennal segment is folded like a finger against the adjacent segment.
Stenodynerus percampanulatus is a solitary mason wasp in the subfamily Eumeninae. The species has been synonymized under Rhynchalastor percampanulatus in some taxonomic treatments. Like other Stenodynerus species, it is a cavity-nesting wasp that provisions nests with paralyzed caterpillars as food for its larvae. The genus is morphologically similar to Parancistrocerus, and the two are often difficult to distinguish in field observations.
thread-legged bug
Stenolemus lanipes is a thread-legged bug in the subfamily Emesinae, characterized by its slender, elongated legs adapted for life on spider webs. This species exhibits highly specialized predatory behavior, feeding almost exclusively on spiders. Laboratory studies have demonstrated that S. lanipes will refuse alternative prey such as Drosophila even when starved, indicating an obligate association with spider predation. The species was described by Wygodzinsky in 1949 and has been recorded from North America.
Stenopogon breviusculoides is a species of robber fly in the family Asilidae, subfamily Stenopogoninae. The species was described by Bromley in 1937. As a member of the Stenopogoninae, it belongs to a group of generally small to medium-sized robber flies. Robber flies in this subfamily are predatory insects that capture other arthropods in flight.
Stenopogon cazieri is a species of robber fly in the family Asilidae, described by Brookman in 1941. The genus Stenopogon belongs to the subfamily Stenopogoninae, a group characterized by distinctive morphological features and predatory habits. Like other asilids, this species is presumed to be an aerial predator of other insects. Very little specific information has been published about this particular species beyond its original description and taxonomic placement.
robber flies
Stenopogoninae is a subfamily of robber flies (Asilidae) containing more than 70 genera and approximately 740 described species. Members are predatory dipterans found across diverse habitats worldwide. The subfamily includes notably small species such as those in the genus Eudioctria (6–8 mm), as well as larger forms. Many species exhibit characteristic perching behaviors on vegetation and are active predators of other insects.
Stenus clavicornis is a species of rove beetle in the family Staphylinidae, subfamily Steninae. Like other members of the genus Stenus, this species possesses the ability to glide on water surfaces using specialized gland secretions that reduce surface tension. The species has been recorded across a broad Palearctic distribution and has been introduced to parts of North America.
Stenus comma is a rove beetle in the family Staphylinidae, notable for its highly specialized predatory behavior. The species employs a unique hunting mechanism using pygidial gland secretions to capture springtails (Collembola). It can eject a viscous, sticky secretion as a droplet on an extendable terminal filament to 'shoot' at prey, or apply the secretion directly during ambush. The beetle demonstrates flexible hunting strategies that adapt to different prey types and defensive capabilities. This species has a broad distribution across the Northern Hemisphere, including Europe, Asia, and North America.
Stenus laccophilus is a rove beetle in the subfamily Steninae, first described by Casey in 1884. Members of this genus possess specialized hunting adaptations including the ability to eject mouthparts using blood pressure to capture prey. The species occurs across northern North America including Canada and the northern United States.
Stenus latissimus is a species of rove beetle in the subfamily Steninae, first described by Bernhauer in 1938. Members of the genus Stenus are known for their specialized hunting adaptations, including the ability to eject mouthparts using blood pressure to capture prey. The species has a transcontinental distribution spanning northern Asia and western North America. As with other Steninae, it is a specialist predator of small invertebrates.
Stenus pubescens is a species of rove beetle in the family Staphylinidae, subfamily Steninae. It is one of numerous species in the large genus Stenus, which is characterized by distinctive adaptations including the ability to glide on water surfaces using specialized gland secretions. The species has a Holarctic distribution, occurring across much of Europe, northern Asia, and North America. Like other members of the genus, it is a predator of small invertebrates.
Stethoconus is a genus of predatory plant bugs in the family Miridae, subfamily Deraeocorinae. Species in this genus are obligate predators of lace bugs (Tingidae) and have been documented as biological control agents for agricultural pests. The genus has been recorded in Asia (Japan, Pakistan) and North America (Florida, USA), with individual species showing specific associations with particular tingid hosts.
Stethoconus praefectus is a predatory plant bug in the family Miridae, subfamily Deraeocorinae, native to South and East Asia and established in the United States. It is an obligatory predator of lace bugs (Tingidae), with documented prey including agricultural pests such as the avocado lace bug (Pseudacysta perseae) and brinjal lace bugs (Urentius hystricellus, Corythauma ayyari). The species has been investigated and utilized as a biological control agent for lace bug infestations in crop systems.
Mite-eating Ladybirds, Spider Mite Destroyers
Stethorus is a genus of minute ladybird beetles (Coccinellidae) commonly known as spider mite destroyers. The genus contains more than 40 described species, though some sources cite at least 20. These beetles are highly specialized predators of spider mites (Tetranychidae) and are recognized as important natural enemies of agricultural pests such as the two-spotted spider mite (Tetranychus urticae) and the European red mite (Panonychus ulmi). Their small size and cryptic coloration make them easily overlooked in field settings.
Stichopogon is a genus of small robber flies (family Asilidae) in the subfamily Dasypogoninae, comprising at least 100 described species worldwide. These diminutive predatory flies are most diverse in arid and semi-arid regions, with strong representation in North America, the Neotropics, North Africa, and the Middle East. The genus is ecologically associated with open, barren habitats—particularly sandy, gravelly, or rocky substrates near water or in dry washes—where they perch low to the ground and ambush small arthropod prey.
Stichopogon abdominalis is a species of robber fly in the family Asilidae. It belongs to the genus Stichopogon, a group of relatively small predatory flies. The species was described by Back in 1909. Information regarding its specific biology, distribution, and ecology remains limited in the available literature.
Stichopogon catulus is a species of robber fly in the family Asilidae. It was described by Osten Sacken in 1887. Like other members of the genus Stichopogon, it is a predatory fly. The species has been documented through 106 iNaturalist observations, indicating it is encountered with moderate frequency by naturalists.
Stichopogon colei is a species of robber fly in the family Asilidae, first described by Bromley in 1934. As with other members of the genus Stichopogon, it is presumed to be a predatory insect. The species is part of a genus containing ten North American species, many of which are associated with sandy or gravelly habitats.
Stichopogon fragilis is a species of robber fly in the family Asilidae, described by Back in 1909. As a member of the genus Stichopogon, it belongs to a group of small, ground-dwelling predatory flies often associated with sandy or barren habitats. The species is poorly documented in available sources, with minimal published information on its biology and distribution beyond taxonomic records.
Three-banded Robber Fly
Stichopogon trifasciatus, commonly known as the three-banded robber fly, is a small predatory fly in the family Asilidae. Adults measure 10–15 mm and are distinguished by three alternating light and dark bands on the abdomen, a bright silvery or blue-gray body, and a preference for barren, sandy or gravelly habitats near water. The species occurs throughout North America from southern Canada to Central America, and south into the Neotropics. Formerly considered a separate species, S. salinus from the western Rocky Mountain region was synonymized with S. trifasciatus in 2010.
Butterfly-wolf Wasps, sand wasps
Stictiella is a genus of sand wasps in the family Crabronidae, established by J. Parker in 1917. The genus comprises at least 14 described species distributed across North America. These solitary wasps are ground-nesting diggers that provision their nests with prey. The common name "Butterfly-wolf Wasps" reflects their documented habit of preying on lepidopteran larvae, particularly skippers (Hesperiidae) and noctuid moths (Noctuidae).
Stilobezzia is a genus of predaceous biting midges in the family Ceratopogonidae, comprising more than 330 described species worldwide. Adult females are predators of other small insects. Immature stages develop in aquatic and semiaquatic habitats. The genus is absent from Antarctica and some islands.
Mantis Shrimps, Stomatopods
Stomatopoda is an order of marine malacostracan crustaceans comprising approximately 450 extant species. Commonly known as mantis shrimps due to their raptorial appendages resembling those of praying mantises, they represent one of the oldest crustacean lineages, having diverged from other malacostracans around 400 million years ago. The order is divided into two functional groups based on raptorial appendage morphology: "smashers" that deliver powerful blunt strikes and "spearers" that impale soft-bodied prey. Stomatopods inhabit tropical to temperate marine waters globally, with greatest diversity in tropical and subtropical regions.
Variegated Meadowhawk
Sympetrum corruptum, commonly known as the Variegated Meadowhawk, is a migratory dragonfly native to North America. It is one of five species tracked by the Migratory Dragonfly Partnership due to its seasonal north-south movements. Adults are notable for their distinctive red-marked coloration and persistence late into autumn, often being the last active dragonflies in many areas. The species is abundant in diverse habitats including wetlands, grasslands, and even agricultural areas like lavender fields.
Horse and Deer Flies, Horse-flies, Deer flies, Gadflies, Clegs, Green-headed flies
Tabanidae is a family of large, agile true flies comprising approximately 4,455 described species worldwide. Adults are characterized by prominent compound eyes, with females possessing widely separated eyes and males having eyes that nearly touch. Females of most species are blood-feeding ectoparasites of mammals, using blade-like mouthparts to lacerate skin and lap blood for egg development, while males feed exclusively on nectar. Larvae are predaceous and develop in semiaquatic or moist soil habitats. The family includes three well-known subfamilies: Tabaninae (horse flies), Chrysopsinae (deer flies), and Pangoniinae.
Tachinusini is a tribe of rove beetles within the subfamily Tachyporinae. Members are small to medium-sized beetles characterized by compact bodies and relatively short elytra that leave several abdominal segments exposed. The tribe includes the genus Tachinus, which is among the more frequently observed tachyporine groups. Tachinusini species are found primarily in the Northern Hemisphere, with many species adapted to cool, moist microhabitats.
rusty spider wasp, red-tailed spider hunter, red-tailed spider wasp
Tachypompilus ferrugineus is a large spider wasp (family Pompilidae) native to the Americas, ranging from Canada through the United States to Central and South America. Adults measure 15–25 mm in length and are characterized by reddish-brown coloration with four narrow dark abdominal bands and distinctive violet-blue wings. Females hunt and paralyze large wandering spiders, particularly wolf spiders (Lycosidae), to provision underground nests for their larvae. Males exhibit perching behavior on elevated structures and compete for access to females. The species includes nine recognized subspecies with variable geographic distributions.
Tachypompilus unicolor cerinus is a subspecies of spider wasp in the family Pompilidae, described by Evans in 1966. It belongs to a genus known for hunting large spiders, particularly wolf spiders and fishing spiders, which are paralyzed and provisioned as food for larval offspring. The subspecies is part of the widespread T. unicolor complex, which exhibits considerable geographic variation across North America. Like other members of its genus, it is solitary and ground-nesting.
Tachyporus is a genus of rove beetles (Staphylinidae) in the tribe Tachyporini, serving as the type genus for both its tribe and subfamily. The genus comprises approximately 35 species in North and Central America alone, with additional species in Europe and other regions. Species such as Tachyporus hypnorum have been extensively studied for their role as generalist predators in agricultural ecosystems, particularly in cereal fields where they contribute to aphid control.
Tachyporus abdominalis is a species of rove beetle in the family Staphylinidae, subfamily Tachyporinae. It is a small, active predatory beetle with a Holarctic distribution spanning North America, Europe, and Asia. The species is part of the diverse Tachyporus genus, which contains numerous similar-looking species that are often difficult to distinguish without close examination. Like other members of its genus, it is typically found in moist habitats where it hunts small invertebrates.