Spider-egg-parasitoid
Guides
Arachnophaga ferruginea
Arachnophaga ferruginea is a species of chalcid wasp in the family Eupelmidae, described by Gahan in 1943. The genus Arachnophaga comprises parasitoid wasps, with species known to attack spider eggs. The specific epithet 'ferruginea' refers to a rusty or iron-colored appearance. Distribution records indicate occurrence in Florida and Virginia, United States.
Geron
Geron is a genus of bee flies in the family Bombyliidae, established by Meigen in 1820. These small to minute flies are characterized by their slender bodies, reduced wing venation, and often distinctive facial markings. Members of this genus are parasitoids, with larvae developing in the egg sacs of spiders. The genus is placed in the subfamily Toxophorinae and tribe Gerontini. Geron species are found across multiple continents including North America and Europe.
Idris
Idris is a large genus of parasitic wasps in the family Scelionidae, first described by Förster in 1856. The genus contains over 300 described species worldwide, with many more remaining undescribed. Most species are egg parasitoids, historically associated with spider eggs, though at least one species has been documented parasitizing stink bug eggs. Members are typically very small, measuring 1–2 mm in length, with reduced wing size that facilitates access to concealed host eggs.
Lymeon
Lymeon is a large genus of ichneumonid wasps in the subfamily Gelinae (tribe Cryptini), containing at least 80 described species with a predominantly Neotropical distribution. The genus is characterized by females that parasitize small cocoons of various insect groups and spider egg-sacs. A taxonomic review recognized 33 North American species, with 28 species recorded from Mexico alone. One documented host association involves a Lymeon species attacking egg-sacs of the orb-weaver spider Araneus vincibilis in Northeastern Brazil, where larvae consumed approximately 80% of spider eggs despite maternal guarding.
Mantispinae
mantidflies, mantispines
Mantispinae is a subfamily of mantidflies (order Neuroptera) comprising at least 30 genera and approximately 310 described species. Adults are characterized by raptorial forelegs adapted for capturing prey, bearing a striking resemblance to praying mantises (Mantodea) due to convergent evolution. Members of this subfamily are distinguished by a larval life history specialized for parasitism of spider egg sacs.
Odontacolus
Odontacolus is a genus of tiny parasitoid wasps in the family Platygastridae, characterized by a distinctive laterally compressed metasomal horn in females. The genus was redefined in 2013 to include Cyphacolus as a junior synonym, expanding the group to encompass species from Africa, Asia, Australia, and the Pacific. All known species are parasitoids of spider eggs, using a specialized ovipositor system to inject eggs into host egg sacs. Species range from 1 to 2.5 mm in length.
Plega signata
Mantidfly, Mantidfly (no common name specific to this species)
Plega signata is a species of mantidfly in the family Mantispidae, first described by Hagen in 1877. Originally placed in the genus Symphrasis, it was later transferred to Plega. Mantidflies are neuropteran insects that exhibit remarkable morphological convergence with praying mantises, possessing raptorial forelegs adapted for capturing prey. The species occurs in Middle America and North America according to distribution records. As with other mantidflies, the larvae are likely parasitoids, though specific host relationships for P. signata remain poorly documented. The genus Plega contains species that are generally less studied than the more common North American mantidflies in the genus Mantispa.
Tromatobia notator
Tromatobia notator is a species of ichneumon wasp in the family Ichneumonidae. It belongs to the genus Tromatobia, which comprises parasitoid wasps that attack spider egg sacs. The species was first described by Fabricius in 1804. Limited observational records exist for this species, with only one documented observation on iNaturalist.
Zeugomantispa minuta
green mantisfly, green mantidfly
Zeugomantispa minuta, commonly known as the green mantisfly, is a small predatory insect in the family Mantispidae. Adults are sit-and-wait predators that use raptorial forelegs to capture prey. Larvae are specialized parasitoids that develop within spider egg sacs, feeding on spider eggs. The species occurs across the Americas from the Caribbean through Central and North America to South America.