Arachnospila fumipennis

Distinguished from similar ground-nesting wasps by: circular, pencil-sized burrow entrances with symmetrical mounds of fine-textured diggings; presence of Buprestidae beetles near nest entrances (versus weevils for Cerceris bicornis or other prey types for different species); and slower, more straight-line flight when carrying prey compared to the erratic flight of unburdened wasps or other species. The three yellow facial markings in females are diagnostic. Burrows differ from tiger beetle larval burrows (smaller, slightly D-shaped with beveled rim) and sand wasp burrows (angled entrance, asymmetric diggings).

Medium-sized wasp with smoky or dark-tinted wings. Females possess three yellow facial markings; males have two. The body is adapted for digging, with modified structures for pushing soil from burrows. Wasps carrying prey appear 'thick-thoraxed' due to holding beetles upside down and head-forward beneath the thorax during flight.

Prefers well-packed sandy or sandy-clay soils in sunny, open areas with sparse vegetation. Frequently nests in anthropogenic habitats including baseball diamonds, practice fields, playgrounds, dirt roads, and campsites. Nests are typically found within flying distance of forested areas where buprestid prey occurs. Shows clear preference for certain fields within a site, with nest densities varying dramatically between adjacent areas.

Native to North America. Present in Norway and Sweden according to GBIF distribution records. In North America, occurs across eastern U.S. and southeastern Canada, with documented populations in Connecticut, Missouri, Louisiana, North Carolina, Maine, Indiana, Michigan, and Ontario. Does not occur in western North America.

Activity period varies with latitude. In North Carolina: late May to early July. In Missouri: late May to late June, with activity dropping as buprestid beetle activity declines. In Ontario: late June to early September. Emergence timing tied to prey availability.

Specialist predator of adult Buprestidae (jewel beetles or metallic wood-boring beetles). Documented prey includes genera Acmaeodera, Actenodes, Agrilus, Anthaxia, Buprestis, Chrysobothris, Dicerca, Poecilonota, and Spectralia. Occasionally captures non-buprestid prey including leaf beetles (Neochlamisus spp., Neochlamisus bebbiana) and weevils, though such records are rare.

• Buprestidae - preyPrimary prey family; nearly exclusive diet
• Agrilus planipennis - preyEmerald ash borer; key target for biosurveillance
• Neochlamisus platani - preyCase-bearing leaf beetle; rare non-buprestid record
• Neochlamisus bebbiana - preyLeaf beetle; documented by Careless et al.

Solitary ground-nesting wasp with one generation per year. Females excavate burrows 10–15 cm deep, angling to one side below the surface before leveling out. Each burrow contains one or more cells provisioned with paralyzed beetles. An egg is laid on the prey, and the cell is sealed with a plug of soil. Larva consumes the paralyzed beetle, pupates, and adult emerges the following season. Nests may be provisioned with single large beetles (Buprestis, Dicerca) or multiple smaller beetles (Agrilus spp.; up to 13 recorded).

Females hunt by capturing beetles in flight or vegetation, paralyzing them with a sting, and transporting them to the nest. Prey is held upside down and head-forward beneath the thorax during flight. Wasps drop prey when threatened and typically do not retrieve it, instead seeking new prey. Nests are often loosely aggregated in colonies of 5–500 individuals. Females spend time identifying their burrow among clustered nests, occasionally landing to search on foot. Males patrol nesting areas and seek mates.

Predator of adult buprestid beetles, potentially influencing local beetle populations. Serves as an efficient sampling tool for buprestid biodiversity, with wasps collecting beetles from canopy habitats difficult for human surveyors to access. May be parasitized by mutillid wasps (Dasymutilla scaevola confirmed).

Primary value is as a biosurveillance tool for emerald ash borer and other invasive or pest buprestids. The 'WaspWatchers' citizen science program trains volunteers to monitor nests and collect beetles, enabling early detection of EAB infestations. Method provides greater effective range (1000–1500 meters) than pheromone-baited traps (~30 meters). Has facilitated discovery of new state records and rare buprestid species. Does not sting humans even when handled. Proposed for use as mobile survey units through nest transplantation.

• Cerceris bicornisConstructs nearly identical burrows but is a weevil specialist; distinguished by presence of weevils rather than buprestids near nest entrances and faster, more powerful flight.
• Bembix americanaSand wasp with similar burrow appearance but burrow enters ground at angle with asymmetric diggings; no beetles found near entrance.
• Cicindelidia punctulataTiger beetle larval burrows are smaller (~5 mm), slightly D-shaped with beveled rim, and lack diggings around entrance.

• biosurveillance
• citizen science
• emerald ash borer
• buprestid predator
• ground-nesting wasp
• WaspWatchers

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• Catalogue of Life
• Working with Cerceris fumipennis—Part 2 | Beetles In The Bush
• Working with Cerceris fumipennis—Part 1 | Beetles In The Bush
• Hymenoptera | Beetles In The Bush | Page 6
• Predatory Wasps and Citizen Scientists are Taking on the Emerald Ash Borer
• Wasp, Geographic Data Improve Surveillance for Emerald Ash Borer