Synanthropic
Guides
Fannia canicularis
Lesser House Fly, Little House Fly
Fannia canicularis, the lesser house fly, is a small dipteran (3.5–6 mm) widespread in association with human habitation and livestock facilities. It is distinguished by its habit of circling in the centers of rooms and its slender build with a straight median wing vein. The species is a significant pest in poultry operations, where larvae develop in accumulated manure. Males exhibit complex swarming behavior in shaded, enclosed sites, performing aerial chases controlled by precise visual-motor mechanisms. Among Fanniidae, this species is most frequently associated with myiasis.
Fannia fuscula
Fannia fuscula is a species of lesser house fly in the family Fanniidae. It is a small, grayish fly distributed across northern Europe and parts of North America. The species belongs to a genus commonly associated with decaying organic matter and synanthropic environments. Like other Fannia species, it is often found in and around human structures.
Fannia pusio
Chicken Dung Fly
Fannia pusio is a small calyptrate fly in the family Fanniidae, commonly known as the chicken dung fly. Native to Central and North America, it has achieved near-global distribution through human-mediated dispersal associated with livestock. The species is notable for its synanthropic association with poultry facilities, where it can reach nuisance-level populations. It has forensic significance as a colonizer of decomposing remains, including buried corpses inaccessible to larger flies, and serves as a developmental indicator for post-mortem interval estimation. Females also function as phoretic hosts for Dermatobia hominis eggs, linking the species to veterinary and medical myiasis cases.
Filistatidae
crevice weavers
Filistatidae are cribellate spiders commonly known as crevice weavers, characterized by their distinctive silk-producing anatomy and retreat-building behavior. Members of this family possess a cribellum—an additional silk-spinning organ—and a calamistrum, a comb of curved hairs on the fourth leg used to card silk into a non-sticky, highly entangling web structure. The family includes synanthropic species that frequently inhabit human structures, as well as species restricted to natural habitats such as arid and semi-arid regions.
Hasarius adansoni
Adanson's house jumper
Hasarius adansoni is a small jumping spider (Salticidae) with pronounced sexual dimorphism. Females reach 8 mm, males 6 mm. Males display distinctive black coloration with a red facial 'mask', white pedipalps, and iridescent white markings on the abdomen. The species is strongly associated with human structures across tropical and subtropical regions worldwide, and has been introduced to temperate areas via greenhouses. It constructs silk retreats at night, approximately twice its body length.
Herpyllus cockerelli
Herpyllus cockerelli is a ground spider in the family Gnaphosidae, distributed across the United States and Mexico. Like other Herpyllus species, it is nocturnal and frequently associated with human structures. The species was described by Nathan Banks in 1901.
Heteroonops spinimanus
Heteroonops spinimanus is a small spider in the family Oonopidae (dwarf goblin spiders), first described by Eugène Simon in 1892. The species has a notably broad distribution, having been recorded across the Americas and subsequently introduced to multiple regions worldwide including Europe, Africa, and the Pacific. Its wide geographic spread suggests human-mediated dispersal, though specific transport mechanisms remain undocumented. As a member of Oonopidae, it belongs to one of the most species-rich spider families, characterized by minute body size and simplified eye arrangements.
Hofmannophila
brown house moth (for sole species H. pseudospretella)
Hofmannophila is a monotypic genus of concealer moths (family Oecophoridae) containing a single species, H. pseudospretella, commonly known as the brown house moth. The genus appears closely related to Borkhausenia. The sole species is a significant synanthropic pest with nearly worldwide distribution, particularly abundant in Britain.
Hydrotaea aenescens
black dump fly, black garbage fly, dump fly
Hydrotaea aenescens, commonly known as the black dump fly or black garbage fly, is a muscid fly native to the New World that has become invasive in Europe. The species is notable for its predatory larvae that feed on house fly (Musca domestica) larvae, making it a candidate for biological control programs in livestock facilities. Adults have been documented as vectors of human botfly eggs. The species exhibits rapid range expansion in Europe, with records extending to the Far North of European Russia.
Hydrotaea ignava
black garbage fly
Hydrotaea ignava is a muscid fly commonly known as the black garbage fly. It is native to Europe, with records from Portugal (including the Azores and Madeira), Denmark, and Norway. The species breeds in moist organic matter, particularly manure and decaying material in confined animal facilities. Its larvae are predatory on other fly larvae, including house fly maggots, and have been used in biological control programs. Adults are distinguished by their shiny bronze-black coloration and habit of remaining on food sources at night rather than dispersing to ceilings or vegetation.
Hypoponera punctatissima
Roger's ant
Hypoponera punctatissima, commonly known as Roger's ant, is a small ponerine ant native to Africa that has become a globally distributed tramp species. The species is strongly associated with human-modified environments, particularly heated buildings, greenhouses, and animal waste. Colonies are small, typically containing approximately 200 workers, and are often polydomous. The species is frequently encountered through alate gynes that appear above ground.
Icius subinermis
Icius subinermis is a jumping spider native to the western Mediterranean region. It shows sexual dimorphism in coloration. The species favors moist habitats near water sources, where it constructs silken retreats in vegetation or under rocks. It has been introduced to several locations outside its native range, including greenhouses in Germany and an established population in Philadelphia, Pennsylvania.
Kukulcania
Crevice Weavers
Kukulcania is a genus of crevice weaver spiders in the family Filistatidae, first described by Pekka T. Lehtinen in 1967 and named after Kukulkan, a Mesoamerican serpent deity. The genus contains fifteen species distributed across the Americas, from the United States through Mexico and Central America to South America. These spiders are characterized by their cribellate silk production and distinctive sexual dimorphism. The most widespread species, Kukulcania hibernalis, is highly synanthropic and has been introduced to multiple regions outside its native range.
Kukulcania arizonica
Arizona black hole spider
Kukulcania arizonica is a crevice-weaving spider native to the southwestern United States, commonly known as the Arizona black hole spider. Females are velvety black with a compact, tarantula-like body form and can live for several years, reaching approximately 13 mm in body length. Males are dramatically different in appearance—pale beige or brown with small bodies and disproportionately long legs. The species constructs distinctive lacy, non-sticky webs that radiate from a silken tube retreat, typically built in crevices on building walls or similar structures. The spider belongs to the cribellate lineage, possessing specialized silk-producing structures that produce entangling rather than adhesive capture threads.
Kukulcania hibernalis
Southern House Spider
Kukulcania hibernalis, commonly known as the Southern House Spider, is a large cribellate spider native to coastal eastern Mexico and the eastern United States. The species exhibits extreme sexual dimorphism: mature females are velvety black or dark gray with a tarantula-like body shape and lumpy eye arrangement, while males are pale beige or brown with small bodies and extremely long legs. Females construct sprawling, lacy, non-sticky webs around tubular retreats on buildings, using specialized cribellar silk with extreme extensibility achieved through a hierarchical loops-on-loops structure. The species is synanthropic and has been introduced widely across the Americas, the Caribbean, Liberia, and the Canary Islands.
Kukulcania hurca
crevice weaver
Kukulcania hurca is a species of crevice weaver spider in the family Filistatidae. It is native to the United States and Mexico. Like other members of its genus, it constructs distinctive lacy, cribellate webs in sheltered locations. The species exhibits pronounced sexual dimorphism, with females appearing velvety black or dark gray and males being pale with elongated legs.
Latridiidae
minute brown scavenger beetles, fungus beetles
Latridiidae is a cosmopolitan family of minute beetles containing approximately 1,050 described species in 29 genera, though true diversity is likely much higher. Adults range from 1.2 to 2 mm in length and are uniformly brown to black in coloration. The family is divided into two subfamilies: Latridiinae (glabrous, heavily sculptured dorsal surface, smooth pronotal margin) and Corticariinae (finely pubescent, lightly sculptured, serrate pronotal margin). Both adults and larvae are obligate mycetophages, feeding exclusively on fungal hyphae and spores.
Latrodectus
widow spiders, black widow spiders, brown widow spiders
Latrodectus is a genus of cobweb spiders (Theridiidae) containing approximately 34-35 species distributed worldwide except Antarctica. Females are typically dark-colored with distinctive reddish ventral abdominal markings, often hourglass-shaped, while males and juveniles frequently display dorsal red or red-and-white patterns. The genus is medically significant due to potent venom containing the neurotoxin latrotoxin, which causes the condition latrodectism. Despite their reputation, bites rarely cause death in humans. The common name "widow spiders" derives from observations of sexual cannibalism, though this behavior is more common in laboratory settings than in nature.
Lepismatidae
Typical Silverfishes
Lepismatidae is a family of primitive, wingless insects in the order Zygentoma, containing approximately 190-340 described species worldwide. The family includes the two most familiar domestic species: the silverfish (Lepisma saccharina) and the firebrat (Thermobia domestica). These ancient insects represent some of the earliest diverging lineages within Insecta, with origins dating back hundreds of millions of years. Members are characterized by elongated, flattened bodies covered in scales, three caudal filaments, and a complete absence of wings throughout their life cycle.
Lithobius melanops
Garden Lithobius, European steppe centipede
Lithobius melanops is a small stone centipede in the order Lithobiomorpha, native to Europe but introduced to many regions worldwide. Adults measure 11–17 mm in length with a dorsoventrally flattened, fusiform body. The species is distinguished by a combination of morphological traits including 32–44 antennal articles, 10–13 ocelli with a notably enlarged posterior ocellus, and specific tergite projections. It inhabits dry, open habitats and is a nocturnal predator of soil invertebrates.
Loxosceles
Recluse Spiders, Brown Spiders, Fiddle-backs, Violin Spiders, Reapers
Loxosceles is a genus of venomous spiders in the family Sicariidae, comprising approximately 149 species of cryptic, reclusive, nocturnal arachnids. These spiders are characterized by their six eyes arranged in three pairs, a distinctive violin-shaped marking on the cephalothorax in many species, and cytotoxic venom that can cause necrotic lesions in some bite victims. The genus has a primarily neotropical distribution, with significant diversity in Brazil and the southwestern United States, though some species have been introduced to other regions through human activity.
Loxosceles devia
Texas Recluse
Loxosceles devia, commonly known as the Texas recluse, is a species of recluse spider in the family Sicariidae. It is native to the southern United States and Mexico. Like other members of the genus Loxosceles, it possesses venom that can cause necrotic skin lesions in humans, though bites are rare and typically occur only when the spider is trapped against skin. The species is closely related to other recluse spiders and shares their characteristic shy, reclusive behavior.
Loxosceles rufescens
Mediterranean recluse spider, violin spider, brown spider
Loxosceles rufescens is a globally invasive recluse spider native to the Mediterranean region. It has established populations across six continents through human-mediated dispersal, often in synanthropic environments. The species is medically significant due to cytotoxic venom containing phospholipases D that can cause loxoscelism—characterized by dermonecrosis, hemolysis, and potential systemic complications. Despite its fearsome reputation, bites are defensive and relatively uncommon even where populations are established.
Machilinae
Machilinae is a subfamily of bristletails within the family Machilidae, comprising one of the two major lineages of the jumping bristletail family. Members are small, wingless insects with the characteristic arched thorax and springing organ (furcula) that enables their distinctive jumping locomotion. The subfamily has been historically distinguished from the other machilid subfamily, Petrobiinae, primarily by subtle differences in abdominal appendage structure and scale patterns. Machilinae species are found across temperate and Mediterranean regions, often occupying rocky, coastal, or urban habitats.
Menemerus semilimbatus
Half-edged Wall Jumping Spider
Menemerus semilimbatus is a medium-sized jumping spider in the family Salticidae, commonly known as the Half-edged Wall Jumping Spider. It is characterized by its dorso-ventrally flattened body, grayish-white coloration with distinctive V-shaped markings on the abdomen, and preference for vertical surfaces. The species is native to the Mediterranean region but has been introduced to parts of the Americas including Argentina, Chile, and the United States.
Micropholcus
cellar spiders
Micropholcus is a genus of cellar spiders (Pholcidae) characterized by long legs and relatively fragile bodies. It is one of only two pholcid genera with both Old and New World distributions, though morphological and ecological differences exist between geographic groups. The genus currently contains at least 29 species, with major taxonomic revisions in 2014 (transfers from Leptopholcus) and 2024 (description of twelve new Old World species). The type species M. fauroti has a pantropical distribution and has been introduced globally.
Micropholcus fauroti
cellar spider
Micropholcus fauroti is a cellar spider (family Pholcidae) with a pantropical distribution. The species has been introduced to Europe, with established records in Belgium and Germany. Approximately 87% of global records fall between the Tropics of Cancer and Capricorn. It is a small-bodied spider associated with human-modified environments in its introduced range.
Modisimus culicinus
cellar spider
Modisimus culicinus is a cellar spider (family Pholcidae) native to South America that has become established across tropical and subtropical regions worldwide through human-mediated dispersal. It is considered a pantropical, synanthropic species strongly associated with human structures. The species was previously classified under the genus Hedypsilus, which has been synonymized with Modisimus.
Musca
house flies, face flies
Musca is a genus of calyptrate flies in the family Muscidae, containing approximately 70 species worldwide. The genus includes Musca domestica, the common house fly, one of the most widespread and synanthropic insects on Earth. Musca species are characterized by their association with human habitation and livestock, with larvae developing in decaying organic matter. Adults are medium-sized, robust flies with distinctive head morphology including aristate antennae and well-developed chaetotaxy.
Musca domestica
house fly, common house fly
Musca domestica is a cosmopolitan synanthropic fly and the most abundant insect in confined cattle operations. Adults are small (6–7 mm), gray with four dark longitudinal stripes on the thorax and creamy yellow abdominal sides. They do not bite but feed on blood, sweat, tears, saliva, and other bodily fluids, causing cattle to exhibit defensive behaviors including ear flapping, head shaking, and feeding hesitancy. The species completes development from egg to adult in as little as two weeks under optimal conditions, with up to 12 generations annually in temperate climates. Females deposit 75–150 eggs per batch in decaying organic matter, particularly manure and rotting vegetation. House flies are mechanical vectors of over 200 pathogens including E. coli, and can infest cattle wounds with maggots.
Muscidae
House Flies and Allies, House Flies, Stable Flies
Muscidae is a family of flies in the superfamily Muscoidea containing nearly 4,000 described species across over 100 genera. The family exhibits diverse feeding strategies: adults may be predatory, hematophagous, saprophagous, or feed on plant and animal exudates including sugar, sweat, tears, and blood. Larvae develop in varied habitats including decaying vegetation, soil, carrion, and freshwater. While some species are synanthropic and of medical importance, most species are not associated with human habitation.
Muscina
false stable flies
Muscina is a genus of muscid flies comprising approximately 27 species with worldwide distribution. The genus includes several synanthropic species frequently associated with livestock facilities, manure, and human structures. M. stabulans (false stable fly) is the most extensively studied species, serving as a model for flight biomechanics research and forensic entomology. Members of this genus are notable for their epidemiological significance as mechanical vectors of pathogens, forensic utility in post-mortem interval estimation, and facultative predatory behavior by third-instar larvae.
Muscina stabulans
False Stable Fly
Muscina stabulans, commonly known as the false stable fly, is a cosmopolitan synanthropic muscid fly distributed worldwide. Adults are medium-sized flies averaging 8 mm in length, distinguished by four dark thoracic stripes, partially reddish-brown legs, and a pale spot above the thorax. The species exhibits strong synanthropic tendencies, with higher abundance in urban-suburban environments compared to rural areas. It has significant economic and public health importance as a mechanical vector of pathogens, a facultative predator of house fly larvae in poultry facilities, and a forensic indicator species for post-mortem interval estimation. Rare cases of intestinal myiasis in humans have been documented.
Muscinae
Muscinae is a subfamily of muscid flies (Diptera: Muscidae) comprising approximately 10 genera and numerous species worldwide. The group includes well-known species such as the house fly (Musca domestica) and related genera including Pyrellia, Ophyra, and Orthellia. Members are characterized by specific morphological features of the adult and immature stages that distinguish them from the sister subfamily Stomoxyinae. The subfamily has significant sanitary and forensic importance due to the synanthropic habits of several species.
Nemapogon granella
European grain worm, European grain moth
A small tineid moth with a wingspan of 10–18 mm, native to the western Palearctic but distributed globally through human activity. Adults display irregular black, white, and grey mottling on the forewings with distinctive black spots along the leading edge. Larvae feed on bracket fungi in natural settings and various stored organic materials in human-associated environments. The species is the type species of genus Nemapogon and subfamily Nemapogoninae.
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.
Nycteola
Nycteola is a genus of spiders in the family Nucteniidae. These spiders are nocturnal orb-weavers that construct webs under eaves and near artificial light sources. They are typically found in association with human structures and buildings.
Oecobiidae
disc web spiders, flatmesh weavers, wall spiders
Oecobiidae is a family of araneomorph spiders containing approximately 130 described species across seven genera. Members are small to moderately sized (2–20 mm body length) and are commonly known as disc web spiders or wall spiders due to their characteristic flat, star-shaped webs constructed on vertical surfaces. The family exhibits distinctive morphological traits including evenly radiating leg placement around the prosoma and a characteristic anal gland bearing a tuft of long hairs. Many species are synanthropic, occurring in and around human dwellings, while others inhabit desert or rocky environments.
Oecobius cellariorum
wall spider
Oecobius cellariorum is a small spider in the family Oecobiidae, commonly known as wall spiders. The species is native to the Mediterranean region and has been introduced to North America and East Asia. It is frequently found in human-built structures.
Oecobius maculatus
Oecobius maculatus is a small spider in the family Oecobiidae, commonly known as wall spiders or disc web spiders. Native to the Mediterranean region extending to Azerbaijan, it has been introduced to the United States and Mexico. The species is characterized by its flattened body form and association with human structures.
Oecobius navus
wall spider, baseboard spider, stucco spider
A small cribellate spider, 2–2.5 mm in body length, native to Europe and Northern Africa but introduced globally. Builds flat, circular webs with lateral openings on artificial structures. Uses an unusual hunting method: running around prey to entangle it in sticky silk ribbons from the anal tubule and spinnerets before biting.
Oinophila
Oinophila is a small genus of fungus moths in the family Tineidae, subfamily Hieroxestinae. The genus name derives from Greek roots meaning "wine-lover," reflecting the association of its best-known species with wine cellars. The genus contains four nominal species, though two are provisionally placed and may not belong to this genus or even to Hieroxestinae. The most notable species, Oinophila v-flava, is commonly known as the wine moth.
Oinophila v-flava
Yellow V Moth
A small tineid moth with a wingspan of approximately 10 mm, widespread across temperate zones worldwide. Adults are active in the evening during summer months in western Europe. The species has established populations in New Zealand since 2001.
Oniscus asellus
common woodlouse, common shiny woodlouse, European sowbug
Oniscus asellus is a large terrestrial isopod native to Western and Northern Europe, and one of the most widespread woodlouse species in the British Isles. It reaches up to 16 mm in length and inhabits diverse moist environments, including rotting wood, gardens, and human structures. The species exhibits biphasic moulting, consuming its shed exoskeleton, and has been documented to fragment weathered polystyrene plastic into microplastics. Two subspecies are recognized: the widespread O. a. asellus and the smaller, more colorful O. a. occidentalis in western France and southeastern Britain.
Opilio
Opilio is a genus of harvestmen (order Opiliones, family Phalangiidae) containing over 60 described species. The genus name derives from Latin "opilio," meaning shepherd or sheep-master. These arachnids are characterized by long legs and a compact, oval body, with species distributed across the Holarctic region. The type species, Phalangium opilio, is a widespread synanthropic predator that has been introduced to North America and other regions.
Ornithonyssus bacoti
tropical rat mite
Ornithonyssus bacoti, commonly called the tropical rat mite, is a hematophagous mesostigmatid mite in the family Macronyssidae. It is an obligate blood-feeding ectoparasite primarily associated with rats and other rodents, but will opportunistically bite humans and domestic animals when primary hosts are unavailable. The mite is of significant medical and veterinary importance due to its role in causing rat mite dermatitis in humans and its potential to vector several pathogens. It exhibits remarkable survival capabilities, traveling hundreds of feet to locate hosts and surviving extended periods without feeding.
Palorus ratzeburgii
small-eyed flour beetle
Palorus ratzeburgii, commonly known as the small-eyed flour beetle, is a darkling beetle in the family Tenebrionidae. It belongs to a genus associated with stored products and grain storage environments. The species is part of a group of beetles often found in human-modified habitats related to food storage.
Parasteatoda
Colourful Comb-footed Spiders
Parasteatoda is a genus of comb-footed spiders (family Theridiidae) first described by Allan Frost Archer in 1946. The genus name derives from Greek "para-" (near) combined with the related genus Steatoda. Species in this genus are characterized by a teardrop-shaped or nearly spherical abdomen with highly variable coloration, and possess the comb-footed spines on the fourth leg typical of theridiids. The genus contains 42 species and one subspecies as of October 2025, distributed primarily across the Old World with many species in Asia and New Guinea, though several have been introduced to the Americas and Europe through human commerce. The best-known member, Parasteatoda tepidariorum (Common House Spider), has become a significant model organism for evolutionary developmental biology research.
Parasteatoda tepidariorum
Common House Spider, American House Spider, Domestic Spider, Common Gray House Spider
Parasteatoda tepidariorum, the common house spider, is a small cobweb-weaving spider native to the Americas that has achieved cosmopolitan distribution through human commerce. It is strongly synanthropic, rarely found outside human-built structures. Females measure 5–8 mm in body length, males 3.8–4.7 mm, with variable coloration from tan to nearly black. The species constructs irregular three-dimensional webs in dark corners of buildings and has become a model organism for developmental biology research due to its short lifecycle, ease of laboratory culture, and accessible embryology.
Phalangium opilio
European Harvestman, Common Harvestman, Brown Harvestman, Daddy Longlegs
Phalangium opilio is the most widespread harvestman species globally, native to Europe and much of Asia and introduced to North America, North Africa, and New Zealand. It is a synanthropic species that thrives in human-modified environments including agricultural fields, gardens, and urban green spaces. The species has become a model organism for arachnid developmental biology and comparative genomics due to its ease of laboratory culture and continuous life cycle. Adults are generalist predators and scavengers that contribute to biological pest control in agricultural systems.