Eichlinia cucurbitae

Adults distinguished from actual wasps by the presence of scales on the body (visible upon close inspection) and the characteristic clear wings with dark borders. The bright orange hind leg patches are a key field mark. Larvae identified by their location inside cucurbit stems accompanied by frass (yellow-green granular excrement) at entry holes. Distinguished from other clearwing moths by host association and the specific pattern of wing venation and body coloration.

Agricultural and garden settings where cucurbit crops are cultivated. Also found in wild habitats where native cucurbits (Cucurbitaceae) occur. Adults are active in open, sunny areas near host plants.

Nearctic and Neotropical regions. Documented throughout eastern and central North America, from southern Canada to northern South America. GBIF records confirm presence in both regions.

Adults active from late spring through summer, with peak activity varying by latitude. Two generations per year typical in temperate zones: first generation emerges in late May to June, second generation in July to August. Overwinters as larvae or pupae in cocoons in soil.

Larvae feed internally on the vascular tissues of cucurbit stems and vines. Host plants include cultivated and wild species in Cucurbitaceae, with strong preference for Cucurbita pepo (pumpkins, squash, zucchini), Cucurbita maxima, and Cucumis melo. Blue Hubbard squash is particularly attractive. Adults do not feed; they rely on larval reserves.

• Cucurbita pepo - larval hostHighly preferred; includes pumpkins, summer squash, zucchini
• Cucurbita maxima - larval hostIncludes Hubbard squash, a favored host
• Cucumis melo - larval hostMelons
• Cucurbita moschata - larval hostButternut squash; less frequently attacked
• Cucurbita argyrosperma - larval hostCushaw squash; relatively resistant

Complete metamorphosis. Eggs hatch in approximately one week. Larvae bore into stems near the soil line or at leaf axils, feeding for 4-6 weeks. Mature larvae exit the plant and spin cocoons in soil, where they pupate. First generation adults emerge in 2-4 weeks; second generation larvae overwinter as prepupae or pupae in cocoons, with adult emergence the following spring. Some populations may have a partial third generation in southern regions.

Adults are diurnal and exhibit wasp-mimicry behavior, including rapid, erratic flight and hovering near vegetation. Females deposit eggs singly on leaf undersides and stems, typically near the base of plants. Larvae tunnel upward and downward in stems, pushing frass out of entry holes. When disturbed, larvae may wriggle vigorously within the stem.

Primary consumer of cucurbit plants; significant agricultural pest. Larval tunneling disrupts water and nutrient transport, leading to plant death. Serves as prey for various predators including birds (which learn to avoid wasp-mimicking adults), parasitoid wasps, and entomopathogenic nematodes. Adults may contribute to pollination incidentally while visiting flowers.

Major economic pest of cucurbit crops in North America. Damage can result in total crop loss in untreated gardens and small farms. Management strategies include floating row covers (removed at flowering to allow pollination), trap cropping with Blue Hubbard squash, manual removal of eggs and larvae, stem injection of entomopathogenic nematodes, and insecticide applications. Subject of ongoing research in integrated pest management and biological control.

• Melittia satyriniformisAnother clearwing moth with similar appearance, but associated with different host plants (primarily wild cucurbits and rarely cultivated species); wing venation and body coloration differ slightly
• Synanthedon spp.Clearwing borers in family Sesiidae, but typically attack woody plants (trees and shrubs) rather than herbaceous vines; adults often have different color patterns and flight periods
• Vespula spp.Yellowjacket wasps which adults mimic; distinguished by two pairs of wings (wasps have one pair plus halteres), scaled body, and different antennal structure

Often mistaken for a wasp or bee due to Batesian mimicry; this confusion can lead to unnecessary fear of the harmless adult moth. The common name 'squash vine borer' is sometimes applied loosely to other stem-boring pests, but properly refers only to this species.

• pest
• agricultural
• clearwing moth
• wasp mimic
• cucurbit
• diurnal moth
• stem borer

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• Catalogue of Life
• Cucurbit catastrophe: Squash vine borer, Melittia cucurbitae — Bug of the Week
• Pumpkin vines on the menu: Squash vine borer, Melittia cucurbitae — Bug of the Week
• White-Eyed Fruit Flies: How Improvements in Gene Editing Could Aid in Pest Management