Brachynemurus abdominalis

Adults can be distinguished from damselflies (order Odonata) by their short, clubbed antennae versus the long, thread-like antennae of damselflies. From other antlion genera, Brachynemurus species can be separated by their relatively large size and specific wing venation patterns. The genus Brachynemurus is distinguished from the pit-digging genus Myrmeleon by larval behavior—Brachynemurus larvae do not construct pits but instead lie in wait buried in loose substrate. Adults are most often seen among tall grasses, especially at dusk, and are frequently attracted to lights at night.

Larvae occur in fine, powdery soil or sandy substrates. They are found in dry, open habitats including areas beneath rock overhangs, under bridges, dirt floors of old barns and sheds, and at the base of trees—situations that remain perpetually dry. Adults frequent grasslands, prairies, and open areas with tall grasses, particularly near dusk.

Found in Central America and North America. Within North America, the genus Brachynemurus occurs across the United States with species recorded from Massachusetts west to Colorado and south through Texas and Florida.

Adults are most commonly observed from late spring through summer. They are frequently attracted to lights at night. Larvae are present year-round in suitable substrates, overwintering in their developmental stage.

Larvae are predatory, feeding on ants and other small insects that come within reach of their jaws. They inject enzymes through hollow mandibles that paralyze prey and begin extra-oral digestion, then imbibe the liquefied tissues. Adults do not feed; their mouthparts are reduced and their attention is focused on reproduction.

Eggs are laid in or on dry soil. Larvae hatch and bury themselves in loose substrate, where they remain for one or more years depending on species and conditions. They pass through three instars, feeding on prey throughout this period. Pupation occurs inside a silken cocoon spun underground, with grains of sand incorporated into the structure. Adults emerge from the puparium and live for a relatively short period, as they do not feed.

Larvae are sit-and-wait predators that remain motionless with jaws agape, sensing vibrations from approaching prey. When prey triggers their trap, they grasp it with their hooked mandibles. Adults are weak, clumsy fliers that are highly cryptic. Upon landing on grass stems or twigs, they instantly align themselves to match the substrate and become nearly invisible. They are most active at dusk.

Larvae function as predators of small soil-dwelling invertebrates, particularly ants, contributing to population regulation of these taxa. Adults serve as prey for various insectivores including birds and other insects. As a group, antlions represent an important component of dry, sandy ecosystem food webs.

Antlions, including Brachynemurus species, are sometimes kept in captivity for observation by providing a container of fine sand and periodically adding prey. They have been used in educational contexts to demonstrate predator-prey relationships and insect metamorphosis. The larvae pose no threat to humans or agriculture.

• Myrmeleon spp.Larvae of Myrmeleon construct distinctive funnel-shaped pits to trap prey, while Brachynemurus larvae simply bury themselves in loose substrate without digging pits. Adult Myrmeleon also have different wing patterns and body proportions.
• Scotoleon spp.Another antlion genus with similar adult morphology, but Scotoleon males have particularly elongated abdomens with prominent claspers, and the genus shows different geographic distribution patterns.
• Damselflies (suborder Zygoptera)Adult antlions superficially resemble damselflies in their slender bodies and wing posture, but are distinguished by short, clubbed antennae versus long, thread-like antennae, and by their net-veined rather than parallel-veined wings.

• antlion
• doodlebug
• Neuroptera
• Myrmeleontidae
• predatory larva
• cryptic adult
• sand-dwelling

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Bug Eric: "Doodlebugs" (Antlions)
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