Ectoparasite
Guides
Felicola
Felicola is a genus of parasitic chewing lice in the family Trichodectidae, established by Ewing in 1929. The genus comprises at least 50 described species, with Felicola subrostratus being the only species known to infest domestic cats. These obligate ectoparasites exhibit high host specificity and are distributed across Europe, Africa, Asia, and Australasia. Infestations are considered uncommon in pet cats but occur more frequently in stray or shelter animals.
Felicola subrostratus
cat biting louse
Felicola subrostratus is a chewing louse (order Psocodea) and the only louse species known to infest domestic cats. It is an obligate ectoparasite with strict host specificity for felids. Infestations cause pediculosis characterized by pruritus, dermatitis, and alopecia, though some cats remain asymptomatic. Long-haired cats typically experience more severe clinical signs. Despite a broad geographic distribution spanning multiple continents, field reports indicate it is uncommon in pet cats and occurs more frequently in stray, shelter, or cattery populations.
Forcipomyia
biting midges, no-see-ums, punkies
Forcipomyia is a large genus of biting midges comprising over 1,000 described species. The genus exhibits remarkable ecological diversity: species in the subgenus Lasiohelea are vertebrate blood-feeders, some species act as ectoparasites on larger insects, and others serve as the exclusive pollinators of cacao (Theobroma cacao), making them essential to chocolate production. This genus belongs to the family Ceratopogonidae and demonstrates one of the highest recorded wing-beat frequencies among insects.
Forcipomyia fuliginosa
Forcipomyia fuliginosa is a biting midge in the family Ceratopogonidae. It exhibits ectoparasitic hemolymphophagy, feeding on the blood of insect larvae. The species has been documented as a pest of the tasar silkworm Antheraea mylitta in India, where preferential landing and blood-feeding behavior on silkworm larvae threatens the sericulture industry. It is one of numerous Forcipomyia species, some of which are notable as pollinators of cacao.
Freyanidae
Freyanidae is a family of feather mites in the order Astigmata, comprising more than 15 genera. Members of this family are ectoparasites or commensals associated with the plumage of birds. They inhabit the feather microenvironment of avian hosts, where they feed on feather materials and associated organic debris. The family is part of the superfamily Pterolichoidea within the mite order Sarcoptiformes.
Fulgoraecia exigua
Planthopper Parasite Moth
Fulgoraecia exigua is a small moth in the family Epipyropidae, commonly known as the planthopper parasite moth. The species is an obligate ectoparasite of planthoppers in the family Issidae, with larvae attaching to and feeding on their hosts. Adults are non-feeding with vestigial mouthparts and short adult lifespans. First described by H. Edwards in 1882, it has been recorded across much of the eastern and central United States, with a first Canadian record documented from southern Ontario in 2021.
Haemaphysalis
Haemaphysalis is the second largest genus of hard ticks (family Ixodidae), comprising approximately 170 species distributed across all continents except Antarctica. The genus is distinguished by morphological features including lateral salience on palpal article II and eyeless adults with short mouthparts. Most species parasitize birds and mammals, with highest diversity concentrated in the Oriental and Afrotropical regions. The Asian longhorned tick (H. longicornis) has emerged as a significant invasive species in North America since 2017.
Haemaphysalis leporispalustris
rabbit tick, grouse tick
Haemaphysalis leporispalustris, commonly known as the rabbit tick, is a hard tick (family Ixodidae) with one of the widest distributions of any New World tick species, ranging from Alaska to Argentina. It is a three-host tick specialized on lagomorph hosts (rabbits and hares), with larvae also frequently found on ground-dwelling birds. Despite rarely feeding on humans, it serves as a vector for several pathogens affecting wildlife and domestic animals, including Rickettsia rickettsii, Coxiella burnetii, and Francisella tularensis. A newly recognized human pathogen, Rickettsia lanei, has been associated with this tick species.
Haematopinidae
ungulate lice
Haematopinidae is a family of sucking lice (suborder Anoplura) containing the single genus Haematopinus. All species are obligate hematophagous ectoparasites of large mammals, particularly ungulates. They are permanent parasites that complete their entire life cycle on the host and cannot survive away from it. Species in this family are significant veterinary pests causing direct damage through blood loss and skin irritation, with documented economic impacts on livestock production.
Haematopinus
ungulate lice, buffalo lice
Haematopinus is a genus of sucking lice and the sole genus in the family Haematopinidae. These obligate ectoparasites are specialized blood-feeders on large mammals, including cattle, horses, pigs, water buffalo, and various wild ungulates. Species within this genus are economically significant veterinary pests that cause direct damage through blood loss and skin irritation, and some are suspected vectors of disease pathogens including anaplasmosis and Brucella abortus. The genus has a global distribution across domestic livestock and wildlife populations.
Haematopinus suis
Hog Louse, Pig Louse
Haematopinus suis, the hog louse, is one of the largest sucking lice (suborder Anoplura), measuring 5–6 mm in length and visible without magnification. It is an obligate ectoparasite of domestic pigs (Sus scrofa domesticus) and wild boars, spending its entire life cycle on the host. The species feeds exclusively on blood, taking multiple meals daily through piercing-sucking mouthparts. Infestations cause severe irritation, hair loss, reduced growth rates, and anemia, with significant economic impacts on pig husbandry worldwide.
Hectopsylla
A genus of stick-tight fleas in the family Tungidae, comprising thirteen species that parasitize non-volant mammals, birds, and bats. The genus was established by Von Frauenfeld in 1860, with H. psittaci as the type species. Several species were described by Karl Jordan between 1906 and 1942. The genus exhibits specialized host attachment behaviors, with females of some species becoming permanently embedded in host skin.
Hectopsylla pulex
chigger flea, stick-tight flea
Hectopsylla pulex is a stick-tight flea and the only member of its genus known to parasitize bats. Females attach permanently to the head region of bats, particularly the ears and tragus, where they feed to repletion, become gravid, and die in situ. This species exhibits a unique reproductive strategy involving autosevering of legs upon host attachment and abdominal expansion through mechanical design rather than true neosomy. Males have never been found attached to hosts and are collected exclusively from bat guano, suggesting pre-host copulation occurs. The species is widely distributed across the Neotropics with records from Brazil, Panama, Colombia, Texas, and Arizona.
Hectopsyllidae
Hectopsyllidae is a small family of fleas containing two genera: Tunga and Hectopsylla. These fleas are obligate ectoparasites of terrestrial mammals, with some species also parasitizing birds and bats. A distinctive feature of the family is neosomy in females, where they undergo extreme swelling and produce new cuticle while remaining permanently attached to the host. The family was formerly known as Tungidae and is closely related to the common fleas (Pulicidae).
Hesperocimex
Hesperocimex is a genus of bed bugs (family Cimicidae) containing at least two described species: H. coloradensis and H. sonorensis. Members of this genus are ectoparasites of birds, specifically associated with nest-dwelling species. H. sonorensis has been documented parasitizing purple martins, woodpeckers, swallows, and Ferruginous Pygmy-Owls.
Hesperoctenes
Hesperoctenes is a genus of parasitic bugs in the family Polyctenidae, first described by Kirkaldy in 1906. Members of this genus are ectoparasites of bats (Chiroptera). The genus is distributed in Colombia and likely broader Neotropical regions, though published records are limited. As polyctenids, they represent a specialized lineage of hemipteran parasites adapted to mammalian hosts.
Hexathrombium
Hexathrombium is a genus of parasitic mites in the family Microtrombidiidae. These mites have been documented as ectoparasites of beetles, specifically recorded from the carabid beetle Ceroglossus buqueti. The genus was established by Cooreman in 1944. As microtrombidiid mites, they likely belong to the parasitic life stage known as the parasitengone life cycle, though specific details for this genus remain limited.
Hippobosca
forest flies, flat flies, iron flies
Hippobosca is a genus of louse flies (family Hippoboscidae) comprising seven described species. These obligate hematophagous ectoparasites exhibit dorso-ventrally flattened bodies adapted for clinging to host hair or feathers. Unlike many hippoboscids that shed wings after host colonization, Hippobosca species retain fully developed wings throughout life, functioning as temporary parasites that repeatedly leave hosts between blood meals. The genus has broad distribution across Europe, Asia, and Africa, with some species introduced to other regions. Several species are of veterinary and medical significance as vectors of bacterial and protozoan pathogens.
Hippobosca longipennis
dog fly, louse fly, blind fly
Hippobosca longipennis is an obligate blood-feeding ectoparasitic fly in the family Hippoboscidae. It primarily infests wild and domestic carnivores, particularly canids and hyaenids, but has been recorded on felids and occasionally humans. The species is larviparous, with females producing 10–15 larvae during a lifetime of four to five months. It serves as an intermediate host for the filarial nematode Dipetalonema dracunculoides (now Acanthocheilonema dracunculoides) and has been implicated as a potential vector for other pathogens. Native to Africa, it has spread to the Middle East, Asia, and parts of Europe through transport on zoo animals and domestic dogs.
Hippoboscidae
louse flies, keds
Hippoboscidae, commonly known as louse flies or keds, are obligate ectoparasites of birds and mammals. The family comprises over 200 species distributed across three subfamilies: Hippoboscinae (mammal parasites), Lipopteninae (deer keds and sheep keds), and Ornithomyinae (bird parasites). Members exhibit dramatic variation in wing morphology, from fully winged forms capable of flight to completely wingless species. Their reproductive strategy is highly unusual among Diptera: females retain and nourish a single larva internally using specialized 'milk glands,' then deposit a fully developed prepupa that immediately pupates.
Hippoboscoidea
Louse Flies, Tsetse Flies, and Allies, Pupipara
Hippoboscoidea is a superfamily of calyptrate flies comprising four families: Glossinidae (tsetse flies), Hippoboscidae (louse flies or ked flies), Nycteribiidae (bat flies), and Streblidae (bat flies). All members are obligate blood-feeding ectoparasites of mammals or birds. The superfamily is distinguished by adenotrophic viviparity, in which larvae develop internally and are deposited as fully-formed prepupae. Some members serve as vectors for significant pathogens, including trypanosomes that cause African sleeping sickness and nagana.
Icosta
Icosta is a genus of louse flies (Hippoboscidae) comprising 52 described species, making it the largest genus in the family. All species are obligate ectoparasites of birds, feeding on blood. The genus has a cosmopolitan distribution excluding Antarctica and is divided into six subgenera based on morphological characteristics. Members are pupiparous, with larvae developing internally and depositing fully formed pupae.
Icosta albipennis
Icosta albipennis is a species of louse fly in the family Hippoboscidae, first described by Thomas Say in 1823. The species is part of a genus of blood-feeding ectoparasitic flies that primarily infest birds. It has been recorded in taxonomic databases with limited observational data available.
Ixodes kingi
Rotund Tick
Ixodes kingi is a hard tick species in the family Ixodidae, commonly known as the Rotund Tick. It is a three-host tick found in prairie and grassland habitats of western North America, where it parasitizes ground-dwelling mammals including prairie dogs, pocket gophers, and ground squirrels. The species exhibits notable size variation between populations east and west of the Rocky Mountains, with larger specimens found in Alberta and smaller specimens in British Columbia. It is an ectoparasite of wildlife but has been documented on domestic animals and humans.
Ixodida
ticks
Ixodida is the order comprising ticks, obligate blood-feeding arachnids within the subclass Acari. The order includes approximately 850-1000 described species worldwide, classified into three families: Ixodidae (hard ticks), Argasidae (soft ticks), and Nuttalliellidae (a monotypic family). Ticks are ectoparasites of mammals, birds, and reptiles, with significant medical and veterinary importance as vectors of bacterial, viral, protozoan, and rickettsial pathogens. They possess a unique life cycle involving multiple developmental stages and host associations.
Lebia subgrandis
Lebia subgrandis is a ground beetle in the family Carabidae, native to Mexico and found in North America. This species has been investigated as a potential biological control agent for the Colorado Potato Beetle (Leptinotarsa decemlineata). Adults are generalist predators of CPB eggs and early instar larvae, while first instar larvae are specialized ectoparasites of CPB prepupae and pupae. The species exhibits a notably narrow host range, refusing alternative prey even when starved.
Leptinus
mammal nest beetles, mouse nest beetles
Leptinus is a genus of small beetles commonly known as mammal nest beetles or mouse nest beetles. These beetles are facultative ectoparasites of small mammals, with species distributed across North America and Europe. The genus contains at least nine species globally, with three described species in North America.
Leptinus orientamericanus
Leptinus orientamericanus is a small beetle in the family Leiodidae, described by Peck in 1982. It is one of three North American species in the genus Leptinus, all of which are facultative ectoparasites of small mammals. This species is widespread east of the Mississippi River and has been documented on seven host species, with highest prevalence on Blarina brevicauda (northern short-tailed shrew) and Scalopus aquaticus (eastern mole). Activity is concentrated during fall and winter months.
Leptopsyllidae
Leptopsyllidae is a family of fleas in the order Siphonaptera, containing at least 30 genera and 250 described species. The family includes ectoparasitic species associated with various mammalian hosts, with some genera showing strong host preferences. Members of this family are distributed across multiple geographic regions, with specific species documented from North America, Europe, and Asia.
Leptus
Leptus is a genus of large mites in the family Erythraeidae, first described by Pierre André Latreille in 1796. The genus comprises approximately 202 species and is distinguished from the related genus Balaustium by the forward placement of eyes on the body. Leptus species are primarily known as ectoparasites, with larvae feeding on various arthropod hosts including bees, harvestmen, and other insects. The genus has been documented across multiple continents including South America, North America, Africa, and Asia.
Lernaeidae
anchorworms
Lernaeidae is a family of parasitic copepods in the order Cyclopoida, commonly known as anchorworms. The family contains approximately 131 species across 20 genera, all of which are obligate ectoparasites of freshwater fishes. Species in this family are characterized by elongated bodies, often with anchor-like holdfast structures used for attachment to host tissues. The most widely distributed and economically significant species is Lernaea cyprinacea, which has been introduced globally and causes substantial damage in aquaculture systems.
Leucospidae
leucospid wasps
Leucospidae are a specialized family of parasitic wasps within the superfamily Chalcidoidea, distinguished by their relatively large size compared to other chalcidoids. They are ectoparasitoids of solitary bees and wasps, with females laying eggs in host nests where larvae attach externally to developing host larvae. The family exhibits distinctive morphological features including enlarged, toothed hind femora and a uniquely recurved ovipositor that extends dorsally along the abdomen in females.
Leucospis
Leucospis is a genus of large chalcidoid wasps in the family Leucospidae. Adults are typically 2–14 mm long with distinctive yellow and black coloration that resembles mason wasps. Females possess a uniquely curved ovipositor that arches over the back, used to drill into wood and reach host larvae in sealed cells. Larvae develop as ectoparasites on solitary bees and wasps, with typically only one parasite emerging per host cell. The genus has a global distribution in tropical and temperate regions.
Leucospis slossonae
Leucospis slossonae is a parasitic wasp in the family Leucospidae, a group of unusually large chalcidoid wasps. Like other leucospids, females possess a distinctive whip-like ovipositor that curls over the top of the abdomen, used to drill into wood and deposit eggs in the nests of solitary bees. The species is known from the southeastern United States.
Linognathidae
sucking lice
Linognathidae is a family of sucking lice in the order Psocodea, containing at least 3 genera (Linognathus, Prolinognathus, Solenopotes) and approximately 70 described species. Members are obligate ectoparasites of mammals, primarily infesting ungulates including cattle, deer, impalas, and related hosts. The family is characterized by piercing-sucking mouthparts adapted for blood-feeding and complete dependence on host animals for survival and reproduction.
Lipoptena
deer ked, louse fly, ked fly
Lipoptena is a genus of louse flies (family Hippoboscidae) comprising approximately 30 described species of obligate blood-feeding ectoparasites primarily associated with deer and other cervids. Adults are initially winged but shed their wings upon locating a host, becoming permanently attached and resembling ticks in appearance. Several species have expanded their ranges through human-mediated transport of hosts, with L. cervi (European deer ked) now invasive in northeastern North America. Members of this genus are increasingly recognized as nuisance pests for hunters and outdoor recreationists, and as potential vectors of bacterial pathogens including Bartonella species.
Lipoptena cervi
Deer Ked, Deer Fly, European Deer Ked
Lipoptena cervi is a blood-feeding ectoparasitic fly in the family Hippoboscidae, commonly known as the deer ked or European deer ked. Native to Eurasia, it has been introduced to North America and is now invasive in the northeastern United States. Adults are initially winged but shed their wings after locating a host, becoming permanently attached to cervid mammals. The species is a significant nuisance to hunters, hikers, and deer processors due to its persistent biting behavior and apparent resistance to common insect repellents.
Lipoptena depressa
Western American deer ked
Lipoptena depressa, the Western American deer ked, is a blood-feeding louse fly (family Hippoboscidae) and ectoparasite specialized on deer. Adults are initially winged but shed wings upon locating a host, after which they remain permanently on the host animal. The species is native to western North America and is one of three Lipoptena species found on the continent.
Lipoptena mazamae
Neotropical deer ked, Neotropical deer louse fly
Lipoptena mazamae is an obligate blood-feeding ectoparasitic fly in the family Hippoboscidae. Adults emerge winged from puparia, then shed their wings permanently upon locating a suitable host. The species is primarily associated with white-tailed deer (Odocoileus virginianus) in the southeastern United States and red brocket deer (Mazama americana) from Mexico to northern Argentina. Both sexes feed on host blood. Females are larviparous, retaining and nourishing a single larva internally until it is ready to pupate.
Lipopteninae
Lipopteninae is a subfamily of louse flies (Hippoboscidae) comprising three genera: Lipoptena, Melophagus, and Neolipoptena. All members are obligate ectoparasites of mammals. The subfamily was established by Speiser in 1908. Species in this group exhibit morphological adaptations for clinging to host fur or hair, including dorsoventrally flattened bodies and strong claws. Notable species include the deer ked (Lipoptena cervi) and the sheep ked (Melophagus ovinus), both of which are economically significant parasites.
Macrocheles
Macrocheles is a genus of mites in the family Macrochelidae, containing over 80 described species. Members of this genus are primarily known for their phoretic associations with insects, particularly flies and beetles, though some species exhibit facultative or obligate parasitism. Research on Macrocheles muscaedomesticae has provided important insights into the evolutionary origins of parasitism from free-living ancestors. Species in this genus occupy diverse habitats including carrion, dung, decaying plant matter, and necrotic cacti, often following their insect hosts to these ephemeral resources.
Melophagus
sheep ked, sheep louse fly, sheep tick
Melophagus is a genus of wingless, blood-feeding flies in the family Hippoboscidae. All species are obligate ectoparasites of cloven-hoofed mammals in the family Bovidae, particularly sheep, cattle, goats, and related wild species. The genus is native to Europe, Asia, and North Africa, but M. ovinus has been introduced worldwide with domestic sheep. These insects spend their entire life cycle on the host, with females giving birth to pupae that attach to wool fibers.
Menacanthus
bird lice, chewing lice
Menacanthus is a genus of chewing lice (Phthiraptera: Menoponidae) that parasitizes birds. The taxonomy is highly uncertain, with recent studies synonymizing dozens of previously recognized species and invalidating other names. Species in this genus feed on blood and feathers by piercing feather quills and gnawing epidermis. They are significant pests of poultry, causing feather loss, reduced egg production, and disease transmission. The genus has a global distribution across all major landmasses.
Menacanthus stramineus
Chicken Body Louse, Poultry Body Louse
Menacanthus stramineus, commonly known as the chicken body louse, is an obligate ectoparasite of domestic chickens (Gallus gallus domesticus). It is the most abundant and widely distributed louse species on poultry worldwide. All life stages occur on the host, where they feed primarily on feathers and skin debris, occasionally consuming blood from pin feathers. Heavy infestations cause feather loss, skin irritation, reduced egg production, and decreased feed conversion efficiency. The species shows temperature-seeking behavior, aggregating in warmer body regions such as the vent, breast, back, and under the wings.
Menoponidae
chicken body lice, chicken body louse family
Menoponidae is a family of chewing lice (suborder Amblycera) comprising ectoparasites of birds. They are frequently called the chicken body louse family due to the economic importance of species like Menacanthus stramineus on poultry, though the family parasitizes diverse avian hosts including migratory birds and passerines. Members possess short antennae concealed in grooves behind the eyes, and many retain partial dependence on blood-feeding through specialized mouthparts such as the hypopharynx. This hematophagous capability allows broader host distribution and reduced microhabitat specialization compared to other chewing lice.
Microlynchia
Microlynchia is a genus of pupiparous louse flies (family Hippoboscidae) comprising four recognized species. All species are obligate ectoparasites of birds. The genus is distinguished from the closely related Pseudolynchia by the presence of minute ocelli and a differently shaped scutellum. Species within Microlynchia exhibit varying degrees of host specificity, with some records indicating associations primarily with Columbiformes (doves and pigeons) while others document broader host ranges across multiple avian orders.
Microlynchia pusilla
lousefly of mourning doves
Microlynchia pusilla is a lousefly (Hippoboscidae) that is a permanent ectoparasite of birds, particularly columbiform hosts. The species exhibits adenotrophic viviparity, with larvae developing internally within the female and deposited as mature, ready-to-pupate larvae on or near the host. Adults are winged upon emergence but permanently shed their wings after locating a host bird, becoming obligate ectoparasites. The species has been recorded from multiple host families but shows particular association with Columbiformes, and has a broad distribution across the Americas from the United States through Brazil.
Nasonia
jewel wasp
Nasonia is a genus of small pteromalid parasitoid wasps comprising four described species: N. vitripennis, N. giraulti, N. longicornis, and N. oneida. These wasps are ectoparasitoids of fly pupae, primarily targeting blow flies and flesh flies. The genus has become a prominent model system in behavioral genetics and evolutionary biology due to its short generation time, ease of laboratory rearing, and the ability to hybridize species in controlled crosses. Nasonia wasps exhibit a distinctive emerald sheen on their exoskeleton, earning them the common name 'jewel wasps.'
Nycteribiidae
bat flies, nycteribiid bat flies
Nycteribiidae is a family of Diptera in the superfamily Hippoboscoidea, commonly known as bat flies. These are obligate ectoparasites of bats, feeding exclusively on blood. They exhibit extreme morphological adaptations for parasitism: complete wing loss, highly reduced or absent compound eyes, and a dorsoventrally flattened, spider-like body with backward-folded legs. The family contains approximately 274 described species distributed primarily in the Old World tropics, with some species in the Neotropics and Europe. Most species show high host specificity, often with one-to-one associations with particular bat species.
Oeciacus
swallow bug, barn swallow bug
Oeciacus is a genus of haematophagous ectoparasites in the family Cimicidae, historically recognized as swallow bugs. Molecular phylogenetic studies have shown the genus to be nested within Cimex, leading to its proposed synonymy with that genus. The three described species—O. hirundinis, O. montandoni, and O. vicarius—are specialized parasites of swallows (Hirundinidae), with distinct morphological characters associated with this host relationship. The American swallow bug O. vicarius is particularly well-studied, occurring primarily in cliff swallow colonies across North America.