Ichneumonid
Guides
Megarhyssa macrurus
Long-tailed Giant Ichneumonid Wasp, Long-tailed Giant Ichneumon Wasp
Megarhyssa macrurus is a large parasitoid wasp and one of the biggest ichneumonids in North America. Females possess an extraordinarily long ovipositor—often exceeding body length—that allows them to reach wood-boring host larvae deep inside decaying trees. The species is a specialist parasitoid of pigeon horntail (Tremex columba) larvae. It occurs across the eastern United States and southern Canada, where it is most commonly observed in summer.
Megarhyssa nortoni
Norton's giant ichneumonid wasp, western giant ichneumonid wasp
Megarhyssa nortoni is a large ichneumonid wasp native to North America, with two recognized subspecies occupying western and eastern ranges. Females possess an extraordinarily long ovipositor reaching 51–76 mm, used to parasitize horntail wasp larvae deep within wood. Despite their formidable appearance, they are harmless to humans and do not sting. The species has been introduced to several countries as a biological control agent for forest pest horntails.
Meringopus serraticaudus
Meringopus serraticaudus is a species of ichneumon wasp described by Pratt in 1945. It belongs to the genus Meringopus within the family Ichneumonidae, a large group of parasitoid wasps. The species epithet 'serraticaudus' refers to a serrated or saw-like tail structure. Very few observations exist, with only two records documented on iNaturalist, indicating it is rarely encountered or poorly known.
Mesoleius
Mesoleius is a genus of ichneumonid parasitoid wasps containing at least 160 described species. The genus is best known from detailed studies of Mesoleius tenthredinis, a biological control agent introduced to North America to manage larch sawfly populations. Species in this genus are endoparasitoids of sawfly larvae, with females depositing eggs directly into host cocoons or larvae. The genus has been documented from Europe and North America.
Mesoleius tenthredinis
larch sawfly parasite
Mesoleius tenthredinis is a parasitoid ichneumonid wasp introduced from Europe to North America as a biological control agent against the larch sawfly (Pristiphora erichsonii). Its embryonic development has been studied in detail, revealing characteristics of primitive endoparasitoids. The species exhibits a notable host-parasite interaction involving encapsulation immunity in some host populations. A putative baculovirus has been detected in ovarian tissues of females.
Mesoleptus ignotus
Mesoleptus ignotus is a species of ichneumon wasp in the family Ichneumonidae, described by Cresson in 1868. The genus Mesoleptus comprises parasitoid wasps, though specific biological details for this species remain poorly documented. The species name "ignotus" (Latin for "unknown") reflects its obscure or poorly characterized status. Available records are sparse, with minimal observational data beyond taxonomic cataloging.
Messatoporus
Messatoporus is a large New World genus of ichneumonid wasps in the subfamily Cryptinae, comprising 89 valid species. The genus is monophyletic and distinguished by a unique combination of morphological synapomorphies including specialized mandible structure and propodeal features. Species exhibit a morphological gradient from forms resembling other Osprynchotina to a highly derived morphotype with convergent traits similar to Gabuniina, interpreted as adaptations for locating and accessing deeply concealed hosts.
Messua
Messua is a genus of jumping spiders (Salticidae) established by G. W. Peckham and E. G. Peckham in 1896. Species in this genus have been documented as hosts for parasitoid wasps, specifically the polysphinctine ichneumonid Inbioia pivai. The genus is moderately well-represented in citizen science observations, with over 3,000 records on iNaturalist.
Metopius galbaneus
Metopius galbaneus is a species of ichneumon wasp described by Townes & Townes in 1959. It belongs to the genus Metopius, a group characterized by distinctive facial modifications in males. The species is known from limited observations, with records primarily from North America. Like other members of Ichneumonidae, it is presumed to be a parasitoid, though specific host associations remain undocumented.
Metopius notatus
Metopius notatus is a species of ichneumon wasp described by Townes & Townes in 1959. The genus Metopius belongs to the family Ichneumonidae, a large group of parasitoid wasps. Very few specific biological observations have been published for this species. Available records are limited to taxonomic documentation and sparse occurrence data.
Neamblymorpha
Neamblymorpha is a genus of ichneumon wasps described by Heinrich in 1960. It belongs to the family Ichneumonidae, one of the largest families of parasitoid wasps. The genus has been documented in the northeastern United States, with records from Vermont. Like other ichneumonids, members of this genus are presumed to be parasitoids, though specific host associations remain poorly documented.
Neamblymorpha milva
Neamblymorpha milva is a species of ichneumon wasp in the family Ichneumonidae. The genus Neamblymorpha is a small group within this large family of parasitoid wasps. This species was described by Ezra Cresson in 1867. Records indicate it occurs in the northeastern United States, with documented observations from Vermont.
Neoxorides
Neoxorides is a genus of ichneumonid wasps in the subfamily Poemeniinae. The genus was established by Clément in 1938 and has undergone taxonomic revision, with some species formerly placed here now reassigned to other genera such as Podoschistus. Members are ectoparasitoids of wood-boring beetle larvae. The genus has a Holarctic distribution, with records from Europe and North America.
Netanyacra
Netanyacra is a genus of ichneumon wasps in the family Ichneumonidae, described by Heinrich in 1968. The genus belongs to the diverse parasitoid wasp lineage within Hymenoptera. Very few observations exist in public databases, with only five records on iNaturalist. Species-level taxonomy and biology remain poorly documented.
Netelia
Orange Ichneumon Wasp, Netelia Wasp
Netelia is a large genus of ichneumonid wasps in the subfamily Tryphoninae, comprising over 330 described species grouped into 12 subgenera. These medium to large wasps are typically orange to brownish-yellow in coloration with conspicuously long antennae and legs. Females possess a prominent ovipositor used to parasitize caterpillar hosts. Unlike many ichneumonids, Netelia females can deliver a painful sting when handled carelessly, using it to temporarily paralyze hosts before egg deposition. The genus is cosmopolitan in distribution and frequently attracted to artificial lights at night.
Notopygus
Notopygus is a genus of ichneumon wasps in the family Ichneumonidae. The genus is poorly documented in scientific literature, with minimal published information on its biology and species diversity. Based on its placement within Ichneumonidae, members are parasitoid wasps, though specific host associations remain unconfirmed. The genus name refers to the characteristic dorsal abdominal structure, with 'noto-' (back) and 'pygus' (rump) alluding to a distinctive posterior feature.
Oedemopsini
Oedemopsini is a tribe of ichneumon wasps within the subfamily Ctenopelmatinae. Members are parasitoid wasps whose larvae develop within host insects. The tribe contains relatively few described genera and species compared to other ctenopelmatine tribes. These wasps are poorly studied, with limited biological data available.
Olesicampe
Olesicampe is a genus of ichneumonid wasps containing at least 130 described species. Species in this genus are parasitoids of sawfly larvae (Hymenoptera: Symphyta), with documented associations to hosts in the genera Pristiphora and Cephalcia. Several species have been introduced as classical biological control agents against larch sawfly and mountain ash sawfly pests in North America, where they have established successfully and achieved significant host population suppression. The genus is native to the Palaearctic region.
Orgichneumon calcatorius
Orgichneumon calcatorius is a species of parasitoid wasp in the family Ichneumonidae, first described by Thunberg in 1822. The species belongs to a genus of medium to large-sized ichneumonids characterized by robust body construction and distinctive leg morphology. As with other members of Ichneumonidae, it is presumed to be a parasitoid of other insects, though specific host records for this species remain poorly documented.
Perilissini
Perilissini is a tribe of ichneumonid wasps within the family Ichneumonidae. These wasps are parasitoids, developing within or upon host organisms. The tribe contains multiple genera distributed across various regions. Members are generally small to medium-sized ichneumonids with specific morphological characteristics distinguishing them from related tribes.
Perithous septemcinctorius
Perithous septemcinctorius is a parasitoid wasp in the family Ichneumonidae, subfamily Pimplinae. The species is known from detailed morphological descriptions of its final instar larva, which exhibits distinctive features including maxillary and labial palpi with more than two sensilla. It is recorded from Belgium and Norway. As a member of the genus Perithous, it is presumed to be a parasitoid, though specific host associations for this species remain poorly documented.
Phaeogenes nigridens
Phaeogenes nigridens is a species of ichneumon wasp described by Wesmael in 1845. The species is currently treated as a synonym of Tycherus nigridens. It belongs to the family Ichneumonidae, a large group of parasitoid wasps. Records indicate presence in Denmark, Norway, and the conterminous United States.
Phytodietus burgessi
Phytodietus burgessi is a species of ichneumonid wasp in the subfamily Ctenopelmatinae. It belongs to a genus whose members are known as koinobiont endoparasitoids of sawfly larvae. The species has been documented in western Canada, particularly in Alberta.
Phytodietus vulgaris
Phytodietus vulgaris is an ichneumonid wasp described by Cresson in 1870. It is a parasitoid species known to attack the orange tortrix moth (Argyrotaenia citrana), a tortricid pest. The species has been documented in western Canada, with records from Alberta and Manitoba. Its life history includes diapause, though specific details require further study.
Picrostigeus
Picrostigeus is a genus of ichneumon wasps in the family Ichneumonidae, established by Förster in 1869. The genus is recorded from Scandinavia, with distribution records from Denmark, Norway, and Sweden. As a member of the Ichneumonidae, species in this genus are parasitoid wasps, though specific biological details remain poorly documented.
Platylabus
Platylabus is a large genus of parasitoid wasps in the family Ichneumonidae, first described by Wesmael in 1845. The genus contains approximately 131 described species with cosmopolitan distribution across multiple continents. As with other ichneumonid wasps, members of this genus are parasitoids, developing within or upon other arthropod hosts. The genus has been documented from Europe, North America, and other regions based on collection records.
Platylabus clarus
Platylabus clarus is a species of ichneumon wasp described by Cresson in 1867. It belongs to the family Ichneumonidae, a large and diverse group of parasitoid wasps. The species has been documented in North America, with records from Canada and the northeastern United States.
Platylabus ornatus
Platylabus ornatus is a species of ichneumon wasp described by Provancher in 1875. It belongs to the family Ichneumonidae, one of the largest families of wasps, characterized by their parasitoid life history. The genus Platylabus is part of the subfamily Ichneumoninae. Very little specific information is available about the biology, distribution, or ecology of this particular species.
Pleolophus
Pleolophus is a genus of ichneumonid parasitoid wasps established by Townes in 1962. Species are native to Europe and have been introduced to North America for biological control of sawfly pests. The genus is notable for its ground-dispersing behavior and density-dependent host discrimination. At least one species, P. basizonus, has been extensively studied for its population dynamics and behavioral ecology in forest ecosystems.
Podoschistus
Podoschistus is a genus of ichneumon wasps in the subfamily Poemeniinae. The genus contains at least one North American species, P. vittifrons, which is an ectoparasitoid of wood-boring beetle larvae. These wasps use their elongated ovipositors to penetrate wood and deposit eggs on beetle grubs concealed within tree boles. The genus has undergone taxonomic revision, having been previously placed in the genera Xorides and Neoxorides.
Poemeniinae
Poemeniinae is a small subfamily of ichneumonid wasps (Hymenoptera: Ichneumonidae) established by Narayanan & Lal in 1953. Members are ectoparasitoids of wood-boring insects, with hosts including beetle larvae (Cerambycidae, Buprestidae) and xylophilous bees (Apoidea). The subfamily exhibits high local species richness in undisturbed forest habitats, particularly in the Carpathian Mountains where up to 95 species of the broader pimpliform group have been documented in a single 250-hectare forest patch. Taxonomic stability has been limited, with genera such as Podoschistus historically transferred between Xorides, Neoxorides, and other groupings.
Polyaulon canadensis
Polyaulon canadensis is a species of ichneumon wasp in the family Ichneumonidae, first described by Harrington in 1894. It belongs to the genus Polyaulon, a group of parasitoid wasps. Very little is known about its biology, host associations, or ecological role. The species name 'canadensis' indicates its occurrence in Canada, though specific distribution details remain poorly documented. Like other ichneumonids, it presumably functions as a parasitoid of other insects, but this has not been directly confirmed for this species.
Polyaulon erythropa
Polyaulon erythropa is a species of ichneumon wasp described by Ashmead in 1890. It belongs to the family Ichneumonidae, one of the largest families of parasitoid wasps. The species is known from very few records, with iNaturalist documenting only two observations. Its specific epithet "erythropa" (from Greek "erythros" meaning red and "pous" meaning foot) suggests reddish leg coloration, though this has not been formally confirmed in modern literature.
Proclitus
Proclitus is a genus of parasitoid wasps in the family Ichneumonidae, established by Förster in 1869. The genus contains approximately 25 described species and exhibits an almost cosmopolitan distribution. Members are parasitoid wasps, though specific host associations remain poorly documented for most species.
Promethes sulcator
Promethes sulcator is a species of ichneumon wasp in the family Ichneumonidae, first described by Gravenhorst in 1829. The species is known from scattered records across central Canada, with observations primarily from Alberta, Manitoba, and Saskatchewan. As a member of the hyperdiverse ichneumonid wasp family, it is presumed to be a parasitoid, though specific host associations remain undocumented. The genus Promethes is relatively small and poorly studied compared to other ichneumonid genera.
Protichneumon grandis
Protichneumon grandis is a species of ichneumon wasp in the family Ichneumonidae, described by Brulle in 1846. The genus Protichneumon belongs to the diverse parasitoid wasp family Ichneumonidae, one of the largest families of insects. Species in this genus are parasitoids, with females laying eggs in or on host insects using their prominent ovipositors. P. grandis has been recorded from several localities across North America including western Canada and the northeastern United States.
Rhyssa
Rhyssa is a genus of large ichneumon wasps in the subfamily Rhyssinae, characterized by exceptionally long ovipositors used to parasitize wood-boring larvae. The genus name derives from Greek meaning "wrinkled." Species in this genus are parasitoids of siricid woodwasps and related wood-boring insects, with females drilling through timber to locate and oviposit on hosts concealed deep within wood. They are distributed across Europe, North Africa, the Near East, North America, the Indomalayan realm, and Australia.
Rhyssa howdenorum
Rhyssa howdenorum is an ichneumonid wasp that parasitizes Sirex nigricornis, a siricid woodwasp pest of pine trees. It was described by Townes in 1960 and has been studied in central Louisiana pine plantations. The species has a single generation per year, with adults emerging from infested loblolly pine logs between mid-August and early November. It serves as a biological control agent against its host, which damages pine timber.
Rhyssella
Rhyssella is a genus of ichneumon wasps in the family Ichneumonidae, containing approximately 10 described species. The genus was established by Rohwer in 1920. Species in this genus are parasitoids of wood-boring insects, with documented associations to wood-wasps in the genus Xiphydria. The genus has a Holarctic distribution, with records from North America, Europe, and Asia.
Rhyssella humida
Rhyssella humida is a species of ichneumon wasp in the family Ichneumonidae. Females possess an exceptionally long ovipositor used to drill into wood to reach host larvae. The species is diurnal and has been documented in North American forested habitats.
Rhyssella nitida
Rhyssella nitida is a diurnal ichneumon wasp in the family Ichneumonidae. The female possesses an exceptionally long ovipositor used to drill into wood and locate host larvae. It is an external parasitoid of wood-wasp larvae in the genus Xiphydria. The species has been documented at blacklight traps, though this appears to be an exception to its normally diurnal activity pattern.
Rubicundiella
Rubicundiella is a genus of ichneumon wasps in the family Ichneumonidae, described by Heinrich in 1961. As a member of this large parasitoid wasp family, species in this genus likely exhibit the slender body form and elongated ovipositor characteristic of many ichneumonids. The genus name suggests a reddish coloration. The 74 iNaturalist observations indicate some level of detectability in the field, though specific biological details remain poorly documented.
Scambus pterophori
Scambus pterophori is a species of ichneumon wasp in the family Ichneumonidae, subfamily Pimplinae. The species epithet "pterophori" suggests an association with plume moths (family Pterophoridae), likely indicating host specificity. Like other Scambus species, it is presumed to be a parasitoid of concealed lepidopteran larvae. The genus Scambus has been subject to taxonomic revision, with some species previously considered distinct now recognized as seasonal morphs of single species.
Setanta compta
Setanta compta is a species of ichneumon wasp in the family Ichneumonidae, first described by Thomas Say in 1835. It is a member of the genus Setanta, a group of parasitoid wasps. The species has been documented in the northeastern United States, with a notable observation record on iNaturalist. Like other ichneumonids, it is presumed to be a parasitoid, though specific host associations for this species remain poorly documented.
Simophion excarinatus
Simophion excarinatus is a species of ichneumon wasp in the family Ichneumonidae, described by Cushman in 1947. The genus Simophion is a relatively small group within the diverse ichneumonid fauna. This species is part of the parasitoid wasp fauna that plays important roles in regulating insect populations. Available records indicate it has been documented in field observations, though detailed biological studies remain limited.
Sinophorus
Sinophorus is a genus of ichneumonid parasitoid wasps established by Förster in 1869. Species are distributed across Europe, Asia, and North America. Members are larval endoparasitoids of Lepidoptera and possibly other insects. The genus includes at least nine described species, with some species such as Sinophorus megalodontis and S. xanthostomus studied for their biological control potential.
Smicroplectrus walleyi
Smicroplectrus walleyi is a species of ichneumonid wasp described by Mason in 1956. It belongs to the genus Smicroplectrus within the large family Ichneumonidae, one of the most diverse families of parasitoid wasps. The species is rarely encountered, with only two observations recorded on iNaturalist as of the available data. Like other members of its family, it is presumed to be a parasitoid of other insects, though specific host associations remain undocumented.
Spudaeus scaber
Spudaeus scaber is a species of ichneumon wasp in the family Ichneumonidae, first described by Gravenhorst in 1829. The genus Spudaeus belongs to the diverse and species-rich ichneumonid wasps, which are parasitoids that play important roles in regulating insect populations. The species has been recorded in Canada (Cypress Hills, Waterton) and parts of Europe (Norway, Sweden). Like other ichneumonids, it is presumed to be a parasitoid wasp, though specific host relationships for this species remain undocumented.
Stenichneumon culpator
Stenichneumon culpator is a species of ichneumon wasp in the family Ichneumonidae. The species is known to hibernate solitarily in tunnels beneath bark, specifically those created by beetles. It has been recorded across parts of Europe including Austria and Belgium.
Stenobarichneumon
Stenobarichneumon is a genus of ichneumon wasps established by Heinrich in 1961. It belongs to the large family Ichneumonidae, one of the most diverse families within Hymenoptera. The genus is documented from Scandinavian countries and contains species that are likely parasitoids of other insects, consistent with the biology of most ichneumonids. Records remain sparse, with limited biological information published.