Euhagena emphytiformis

Distinguished from its congener Euhagena nebraskae by geographic range: E. emphytiformis occurs in eastern North America (e.g., Missouri, Jefferson County glades) while E. nebraskae is western, ranging across the Great Plains to California. Sexual dimorphism is pronounced: males have bipectinate antennae versus simple female antennae, smaller body size, denser thoracic and cephalic setation, and more extensive white abdominal and wing markings. The species can be separated from other sesiid clearwings by its specific pheromone attractant and larval host association with Onagraceae.

Adults exhibit transparent wings with reduced scaling, characteristic of clearwing moths. Males possess highly bipectinate (comb-like) antennae with teeth on both sides, while females have simple antennae. Males are smaller than females, with hairier heads and thoraxes and greater white coloration on the abdomen and wings. The body is wasp-like in overall form, contributing to effective mimicry of hymenopterans.

Recorded from glade habitats in Jefferson County, Missouri, where evening primrose species (Oenothera gaura and Oenothera macrocarpa) occur. The open, rocky glade environment with exposed substrates appears to support the larval host plants.

Eastern North America. Documented in Missouri (Jefferson County glades south of St. Louis). GBIF records indicate broader Nearctic and Neotropical presence, though specific localities beyond the Missouri records require verification.

Adult activity has been documented in the 1980s timeframe; specific months not explicitly stated in source material. Related species E. nebraskae is active in late fall (October-November), but direct transfer of this timing to E. emphytiformis is not confirmed.

Larvae develop in the roots of plants in the evening primrose family (Onagraceae). Specific host plants include Oenothera gaura and/or Oenothera macrocarpa in the Missouri glade habitat. Adult feeding habits unknown.

• Oenothera gaura - larval hostPresumed host in Jefferson County glades
• Oenothera macrocarpa - larval hostPresumed host in Jefferson County glades

Larvae are root-borers in Onagraceae plants. Adult emergence and mating behavior documented: females raise tufted abdominal tips with scales spread, apparently releasing pheromone. Complete life cycle details otherwise unknown.

Males use bipectinate antennae to detect female pheromones. Adults are attracted to synthetic pheromone lures. Females exhibit calling behavior with elevated, tufted abdominal tips. The species is a convincing wasp mimic in flight, which may reduce predation.

Root-borer in native Onagraceae plants; likely contributes to population dynamics of evening primrose species in glade ecosystems. Specific ecological impacts unknown.

Has been monitored using synthetic pheromones for research purposes. Not documented as a significant agricultural or ornamental pest. Interest to entomologists due to wasp mimicry and clearwing morphology.

• Euhagena nebraskaeCongener with similar wasp-mimic clearwing morphology, but geographically separated: E. nebraskae is western (Great Plains to California), while E. emphytiformis is eastern. E. nebraskae exhibits late fall activity (October-November) and excessive adult hairiness presumably adapted to cold conditions at high elevations.
• Synanthedon scitulaAnother sesiid clearwing moth, but differs in host association (dogwood) and attraction to blacklight rather than specific Onagraceae-associated pheromones.
• Synanthedon acerniMaple borer sesiid, distinguished by host plant (Acer) and different pheromone chemistry.

• clearwing moth
• root borer
• wasp mimic
• glade inhabitant
• Onagraceae associate

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Euhagena nebraskae in Kansas | Beetles In The Bush