Mymarommatoidea

Distinguished from Chalcidoidea and other minute parasitoid wasps by the unique racket-shaped fore wing with narrow stalk and expanded distal portion. The accordion-like head contraction mechanism and exodont mandibles are additional diagnostic features. Extinct families (Alavarommatidae, Dipterommatidae, Gallorommatidae) known only from Cretaceous amber.

Extremely small wasps, most approximately 0.3 mm in total body length. Fore wings distinctive: racket-shaped with narrow stalk and expanded membranous portion. Head capable of accordion-like contraction due to pleated membrane connecting convex frontal plate to flat occipital plate. Mandibles exodont (teeth pointing outward). Ovipositor short, non-telescopic, concealed at rest beneath hypopygium.

Forest environments including maquis shrublands, holm oak forests, and deciduous leaf litter. Collected from coastal areas to elevations exceeding 1000 m. Hawaiian population associated with Ficus microcarpa branches.

Global distribution with records from North America (Canada), Europe (France, Spain, UK, Belgium, Switzerland, Italy, Germany, Norway, Denmark, Sweden, Finland, Czech Republic, Poland, Hungary, Romania, Bulgaria, Russia), eastern Asia (China, Japan, Philippines), and Hawaiian Islands. Two species in one genus recorded from Canada. First documented from Corsica in 2021.

Adults captured June through October in Mediterranean regions (Corsica, Vaucluse); July through September in central and northern Europe (Czech Republic, Finland). Multiple generations per year suggested.

• Lepidopsocus sp. - egg parasitoidConfirmed host for Mymaromma menehune in Hawaii; only confirmed host record for entire superfamily. M. anomalum and other Mymarommatidae hypothesized to parasitize barklice (Psocodea) eggs based on shared distribution, habitat, and phenology, but not directly confirmed.

Solitary endoparasitoid development within host eggs. Adults emerge from host eggs; extendable head and exodont mandibles facilitate emergence by rupturing soft chorion. Multiple generations per year inferred from extended adult flight period.

Head contracts antero-posteriorly like an accordion, enabled by pleated membrane between frontal and occipital plates. Exodont mandibles likely facilitate movement through silk networks protecting barklice eggs.

Egg parasitoid, likely regulating populations of barklice (Psocodea: Lepidopsocidae) in forest ecosystems. Position in food web as hyperparasitoid or primary parasitoid not determined.

• ChalcidoideaSimilar minute size and parasitoid lifestyle, but distinguished by wing venation and head structure; Mymarommatoidea has unique racket-shaped fore wings and accordion-like head contraction not found in Chalcidoidea.

• parasitoid
• microscopic
• egg parasitoid
• Cretaceous relict
• barklice parasitoid

• BugGuide
• Wikipedia
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Checklist of Chalcidoidea and Mymarommatoidea (Hymenoptera) of Canada, Alaska and Greenland
• Mymarommatidae, new family and superfamily of parasitoid wasps for Corsica (Hymenoptera, Mymarommatoidea)
• A new Mymaromma sp. (Mymarommatoidea, Mymarommatidae) in Hawai‘i and first host record for the superfamily
• Biology, ecology, and taxonomy of the parasitoids of the families Austroniidae, Peradeniidae, Proctorenyxidae, Roproniidae, and Vanhorniidae (Hymenoptera: Proctotrupoidea) and family Mymarommatidae (Hymenoptera: Proctotrupomorpha: Mymarommatoidea)
• Critical checklist of the Chalcidoidea and Mymarommatoidea (Insecta, Hymenoptera) of Germany.