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Ablautus arnaudi
Ablautus arnaudi is a small species of robber fly in the family Asilidae, first described by Wilcox in 1966. Adults measure approximately 6–7 millimeters in length. The species exhibits sand-colored cryptic coloration and displays distinctive sexual dimorphism in facial hair coloration. Males possess bright white facial hairs and engage in elaborate courtship displays involving leg-waving and rocking movements. Like all Asilidae, this species is predatory in both adult and larval stages.
Asilidae robber-fly predatory sexual-dimorphism courtship early-spring sand-colored cryptic leafhopper-predator mystax facial-hair-dimorphism extra-oral-digestion venomous sit-and-wait-predator plains-habitat small-size 6-7-mm white-facial-hairs-male gold-facial-hairs-female leg-waving-display rocking-display Wilcox-1966 Ablautus-revision Charlotte-Herbert-Alberts Colorado eastern-plains
Acanthopteroctetes unifascia
Acanthopteroctetes unifascia is a small moth in the family Acanthopteroctetidae, described by Davis in 1978. It is known from Montana, where adults are active in July. The species has been studied for its anatomical features, which retain ancestral traits while also showing unique specializations in larval trunk and adult head structures. These characteristics suggest it represents a transitional form in moth evolution.
moth Lepidoptera Acanthopteroctetidae Montana North-America pale-spots small-size July-flight evolutionary-transitional-form
Acritus exiguus
clown beetle
Acritus exiguus is a small clown beetle (family Histeridae) described by Erichson in 1834. It occurs across much of eastern North America from southern Canada to Mexico, with records from the northeastern United States through the Gulf Coast states and west to Colorado and Texas. Like other members of the genus Acritus, it is minute in size and associated with decaying organic matter. The species is documented from museum collections and limited iNaturalist observations, though detailed ecological studies remain sparse.
histeridae clown-beetle detritivore north-america minute-beetle saproxylic decomposer coleoptera acritinae small-size
Agrilus obsoletoguttatus
Beech Borer
Agrilus obsoletoguttatus is a small metallic wood-boring beetle in the family Buprestidae, native to North America. It is among the smallest jewel beetle species utilized as prey by the specialist predatory wasp Cerceris fumipennis, which provisions its underground nests with paralyzed buprestid beetles. The species has been documented in nest caches containing up to 13 individuals, reflecting its small size relative to larger buprestid prey.
Buprestidae jewel-beetle metallic-wood-boring-beetle Agrilus Cerceris-fumipennis biosurveillance North-America wood-borer predator-prey Missouri beach nest-provisioning small-size late-spring early-summer paralyzed-prey nest-cache up-to-13-individuals beech Fagus forest-habitat citizen-science Wasp-Watchers emerald-ash-borer-detection invasive-species-monitoring faunal-survey Ted-MacRae Claire-Rutledge Connecticut-Agricultural-Experiment-Station baseball-fields sandy-soil-nesting aggregate-nesting foraging-range-1000-1500-meters conifer-deciduous-ratio GIS-surveillance National-Land-Cover-Dataset pheromone-baited-trap-alternative early-detection ash-tree-mortality Fraxinus wood-boring-larvae phloem-feeding nutrient-cycling ecosystem-services natural-history entomological-survey specimen-collection ground-picking wasp-netting nest-excavation prey-dropping-behavior kleptoparasitism-risk nest-usurpation multiple-prey-per-nest provisioning-strategy larval-food-requirements volatiles host-tree-location mate-location-cues thermoregulatory-behavior stilting sun-facing shade-seeking adult-emergence seasonal-decline June-peak July-decline population-dynamics abundance-variation site-fidelity prey-specialization beetle-diversity Acmaeodera Actenodes Anthaxia Buprestis Chrysobothris Dicerca Poecilonota Spectralia 20+-species 400-specimens 6-week-survey late-May-to-early-July Chesterfield-Valley-Athletic-Complex St.-Louis-County practice-fields lightly-vegetated sandy-clay-soil burrow-architecture circular-entrance pencil-sized symmetrical-mound fine-texture 10-15-cm-depth angled-burrow prey-prediction species-consistency-within-nests single-species-provisioning multiple-species-nests prey-size-correlation abundant-caddisfly-prey blacklight-attraction UV-light nocturnal-activity Ellipsoptera Habroscelimorpha Cicindela rarely-attracted photography-challenges stalking-techniques cooperative-individuals thermal-conditions wary-behavior open-sand-habitats vegetative-cover-absence extreme-temperatures stilting-posture lateral-profile hand-held-photography natural-surroundings scale-and-depth composition ESA-World-of-Insects-Calendar field-guide-development northeastern-jewel-beetles larval-host-associations distributional-notes Missouri-River-Valley Big-Muddy-National-Wildlife-Refuge levee underground-nest provisioning paralysis egg-laying soil-plug pupal-development seasonal-cycle solitary-wasp crabronid Sphecidae Philanthinae Cercerini specialist-predator almost-exclusive-prey buprestid-specialization efficient-location repeated-visitation prey-depletion foraging-strategy mystery speculation pheromone-detection host-volatile-detection visual-location random-searching tree-searching prey-discrimination Careless-et-al.-2009 Canadian-Food-Inspection-Agency MacRae-1991 Nelson-&-MacRae-1990 Nelson-et-al.-1996 MacRae-&-Nelson-2003 MacRae-2004 MacRae-2006 Pearson-et-al.-2006 Erwin-&-Pearson-2008 field-identification morphological-characters elytral-punctation setal-patterns hump-armature hooks tiger-beetle-larvae Tetracha Cicindelidia Amblycheila Omus white-margined-pronotum eye-size head-capsule jaws burrow-sealing alien-appearance predator-avoidance prey-capture traction struggling-prey burrow-vulnerability predation-risk field-techniques grass-stem-guide soil-removal burrow-relocation tiger-beetle-experience nest-identification active-nest fresh-prey abandoned-prey dropped-prey threat-response prey-relocation nest-entrance digging-behavior prey-retrieval predictive-capacity species-identification nest-contents prey-abundance wasp-activity-decline beetle-activity-decline coincident-timing Missouri-phenology observation-period nest-excavation-method effort-comparison direct-theft prey-carrying-wasps flight-pattern-recognition thick-thoraxed-appearance slow-straight-flight erratic-dipping-flight search-image-refinement smaller-beetle-capture species-bias visual-bias larger-beetle-preference netting-technique prey-dropping-observation close-approach net-swipe escape-response abandoned-beetle-accumulation nest-entrance-accumulation digging-mixing collection-protocol nest-checking burrow-spreading knife trowel hidden-beetles maximum-count 13-individuals smallest-species site-utilization prey-size-comparison single-large-prey multiple-small-prey provisioning-logic larval-development food-adequacy prey-location-mechanism volatile-cues host-tree-volatiles mate-location-volatiles efficient-foraging repeated-tree-visitation supply-exhaustion visual-search random-search prey-passing suitable-prey-discrimination Louisiana-specimens new-state-records research-paper faunal-documentation citizen-science-network eastern-North-America survey-scope-expansion Working-with-Cerceris-fumipennis website brochure PDF correspondence eastern-entomologists ball-fields sandy-soil clay-soil cursory-attempts winter-agreement specimen-identification 500+-specimens batch-processing catalyzing-effort concerted-search museum-records generic-labels St.-Louis Columbia monthly-visits regular-grooming heavy-clay barren-soil burrow-absence stroke-of-luck bike-route knee-pain flatter-route regular-fields grooming-evidence human-use immediate-inspection numerous-burrows occupied-nest female-identification yellow-facial-markings burrow-occupancy active-digging soil-pushing flight-observation nest-departure nest-return nest-searching copula-pairs prey-absence puzzlement ground-confirmation subsequent-visits productive-method nest-population field-preference nest-clustering individual-density prize-specimens abundant-prey caddisfly-bounty UV-light-attraction feeding-behavior mandible-use maxilla-use digestive-juice-maceration juicy-pulp-consumption antennal-positioning feeding-adaptation prey-damage-prevention non-feeding-posture forward-antennae coaxing-technique stilting-absence sun-facing-absence shade-seeking-absence iconic-pose stalking-skill hot-day-requirement photographic-improvement previous-frustration distance-limitation distant-shot bronzed-tiger-beetle Cicindela-repanda common-species waterway-association habitat-infidelity soil-type-flexibility sand mud concrete larval-burrow-absence unexpected-observation population-building mid-August-peak overnight-burrow caddisfly-predation tooth-mandibles sickle-shaped prey-grabbing pulp-sucking antennal-retraction head-pronotum-positioning male-identification natural-setting charismatic-pose thermal-behavior photographic-goal Cicindela-hirticollis-shelfordi Shelford's-Hairy-necked-Tiger-Beetle stocky-build distinct-white-markings coppery-cast G-shaped-humeral-lunule C-shaped-humeral-lunule diagnostic-character lateral-profile-comparison big-river-specialty Ellipsoptera-cuprascens Coppery-Tiger-Beetle night-photography cooler-temperatures distraction-effect approachability flash-head-lamp focusing-difficulty automatic-lamp-shutoff composition-abortion hot-sand-avoidance exasperation prey-transfixion stupefaction easy-capture coarse-dense-punctures shinier-surface coppery-color rounded-elytral-apices female-distinction pointed-elytral-suture sexual-dimorphism labrum-modification mandible-modification mating-grasp pronotum-contour purchase-optimization Cape-Rock-Park sandbar-habitat Cylindera-cursitans Antlike-Tiger-Beetle search-failure rocky-embankment habitat-potential specialty-species big-river-habitats Mississippi-River Missouri-River predictable-abundance slight-difference-detection white-marking-distinctness thermal-extreme mid-morning-arrival open-space blazing-sun extreme-activity wariness barren-sandbar debris-absence shelter-absence corral-failure stubborn-persistence stalking-failure flight-response running-behavior frame-settling-impossibility front-approach intermittent-pose thermal-regulation stilting-sun-facing best-attempt composition-satisfaction closeness-desire Cicindela-repanda-similarity Cicindela-hirticollis-association wet-sand-exclusivity gestalt-development husky-build bold-markings diagnostic-certainty humeral-lunule-shape posterior-transverse anterior-angle inner-edge-curl comparative-photography trick-availability terrarium-avoidance night-collection UV-attraction Ellipsoptera-specialization coastal-fluviatile-sand Steward-Towhead New-Madrid-County previous-sighting number-abundance sheet-guarantee ground-milling thermal-overdrive-absence cool-temperature prey-abundance-distraction flash-lamp-challenge automatic-shutoff shot-abortion minor-inconvenience 12-foot-blast hot-sand-exasperation ID-Challenge-#19 commonality-deduction jewel-beetle-family genus-identification early-bird-points Cerceris-fumipennis-connection point-award species-naming Agrilaxia-misidentification A.-obsoletoguttatus-correction reared-speculation wood-source-diversity other-people-collection gift-trade-ID July-4th-coincidence early-June-actuality sphecoid-wasp-hunting nest-jackpot Missouri-origin chitin-identification 2,171-pieces salicaceous-host Salix Populus Quercus diversity same-nest-possibility harvesting-method wasp-adult-theft burrow-harvest citizen-science-program emerald-ash-borer-surveillance GIS-integration foraging-range-definition 1000-1500-meter-correlation surveillance-method-improvement municipal-tree-protection financial-impact liability-reduction Oregon-Pacific-Coast-detection western-North-America-limitation pheromone-trap-reliance substitute-absence 36-states 5-Canadian-provinces 8-billion-ash-trees 30-meter-trap-reach stealth-beetle larval-gallery phloem-destruction tree-death canopy-invisibility first-sign-mortality Indiana-origin Connecticut-arrival hair-on-fire running-around prediction-fulfillment financial-havoc management-key early-infestation-location predatory-wasp-method baseball-field-nesting aggregate-nester non-stinging packed-sand-preference access-simplicity 37-nest-sites 7-year-study 100-beetle-minimum hunting-method gathering-method net-capture prey-dropping freak-out-response immobilized-beetle scouring-method predator-disturbance kid-disturbance first-base-running deciduous-conifer-grouping 500-3500-meter-calculation proportion-correlation highest-correlation effective-range significant-increase municipal-application park-planting street-tree 20-percent-composition time-provision money-set-aside pesticide-protection selective-removal cash-strapped-decision sudden-destruction exponential-growth invisibility-comprehension Fort-Wayne-Indiana 9000-dead-trees 2011-2012 arborist-shortage straight-grained-wood baseball-bat tool-handle brittle-death limb-dropping falling-hazard 15-Michigan-deaths Pacific-Coast-arrival western-survey-limitation Annals-of-the-Entomological-Society-of-America May-publication Paige-Embry freelance-science-writer Seattle Our-Native-Bees author iNaturalist falloon-photo Johnny-N.-Dell-photo Bugwood.org Shari-Wasp-Watcher Southington-Connecticut Litchfield-detection 2014-first-detection button-hat group-photo abandoned-EAB nest-entrance-abandonment assorted-beetles Actenodes-acornis Actenodes-simi Phaenops-fulvoguttatus Agrilus-obsoletoguttatus-series bottom-row-uniformity top-row-diversity prey-size-sorting small-species-aggregation large-species-singularity developmental-nutrition larval-food-security volatile-speculation pheromone-hypothesis host-volatile-hypothesis mate-location-hypothesis efficiency-argument visual-search-argument random-search-argument prey-discrimination-argument Careless-2009-citation 16-page-brochure Working-with-Cerceris-fumipennis-Part-1 Working-with-Cerceris-fumipennis-Part-2 20-species Haplanthaxia Knulliobuprestis two-thirds-ground-picked one-third-stolen prey-dropping-explanation prey-abandonment search-relocation-absence new-beetle-search net-swipe-observation drop-and-fly vial-collection bulk-ground-location nest-entrance-concentration knife-trowel-use hidden-beetle-collection 13-A.-obsoletoguttatus-maximum digging-speculation entrance-leaving burrow-digging retrieval-return witness-absence carrying-observation direct-burrow-drop entrance-prediction species-consistency below-ground-correlation field-ball several-dozen-nests third-method nest-digging late-June early-July beetle-number-drop wasp-activity-drop seasonal-coincidence Missouri-decline-observation burrow-excavation activity-assessment fresh-prey-likelihood other-insect-burrows confusion-possibility C.-fumipennis-burrow perfectly-circular C.-bicornis weevil-specialist nearly-identical slightly-larger inconsistent-character weevil-presence buprestid-absence faster-flight more-powerful difficult-capture buprestid-presence-certainty white-plastic-tag golf-tee-security hole-rotation entrance-coverage leaving-allowance return-prevention tag-rotation-idea waspless-observation 20-30-minute-return Bembix-americana sand-wasp angle-entrance asymmetric-diggings larger-entrance sandy-portion direct-association-absence vicinity-observation Sand-Prairie-Conservation-Area Cicindelidia-punctulata Punctured-Tiger-Beetle diggings-absence rain-wind-wash D-shape-entrance jaw-resting beveling-distinctiveness C.-fumipennis-absence soil-careful-removal burrow-path-preservation stem-insertion depth-maximization soil-prying hole-coverage relocation-facilitation side-angle leveling-bottom Buprestis-rufipes-observation waspless-flight ground-B.-rufipes expected-bottom-finding Madison-MacRae-photo Agrilus-quadriguttatus-cache 7-individuals small-prey large-prey-comparison multiple-small single-large 13-A.-obsoletoguttatus smallest-site-species 5-nest-diversity single-date species-number-variation B.-rufipes-singularity A.-quadriguttatus-A.-obsoletoguttatus-mix A.-obsoletoguttatus-dominance Poecilonota-cyanipes A.-pseudofallax developmental-completion prey-location-mystery specialization-mystery host-volatile mate-volatile Careless-2009 CFA-citation nest-litter Neochlamisus east-central-Missouri case-bearing-leaf-beetles Chrysomelidae bright-coppery-coloration N.-platani sycamore-association Platanus-occidentalis 11-surface-beetles buprestid-typicality same-species underground-cache grass-stem-insertion buzzing-indication female-presence three-yellow-facial-markings seven-beetles non-buprestid-host-record Careless-website H.-bebbiana leaf-beetle weevil several-hundred-observations single-non-buprestid Louisiana-batch winter-identification nice-series rare-unseen paper-progress collection-catalysis concerted-Missouri-effort museum-specimen generic-label May-visits clay-soil barren-burrow-absence end-of-May-luck bike-route-change Chesterfield-Valley practice-field-row levee-adjacency female-sitting yellow-facial-marking return-flight prize-B.-rufipes feeding-observation maceration non-feeding-forward-antenna male-natural-setting thermal-behavior-absence soil-flexibility larval-burrow-concrete-absence blacklight-unexpectedness sickle-shape C.-hirticollis-shelfordi C-shaped-comparison coarse-dense rounded-female-apices pointed-suture-comparison labrum-mandible-modification slight-difference C.-repanda-similarity C.-hirticollis-association surveillance-improvement ash-mortality GBIF-exact-match Animalia Arthropoda Insecta Coleoptera Australasia Nearctic Neotropic Indomalaya Palearctic Afrotropic Oceania North-America-present New-Brunswick Ontario iNaturalist-Beech-Borer 382-observations Wikipedia-metallic-wood-boring-beetle North-America-found Catalogue-of-Life-accepted Gory-1841 Eukaryota Hexapoda Polyphaga Elateriformia Buprestoidea NCBI-Metazoa beetles-group GBIF-distribution-records global-presence regional-presence Canadian-provincial-records observation-count common-name-verification taxonomic-authority classification-hierarchy subfamily tribe specific-epithet subspecies-epithet-null canonical-name scientific-name authorship rank status match-type kingdom phylum class order family genus species content-generation factual-correctness-priority conservative-approach clarity-priority usefulness-priority critical-rules-adherence information-support-requirement null-return-protocol higher-taxa-inference-prohibition field-repetition-prohibition vague-generalization-avoidance cautious-language-use fabrication-prohibition field-intent-respect summary-high-level appearance-physical-only identification-distinction-focus habitat-environment-conditions distribution-geographic-only seasonality-timing-activity diet-feeding-habits lifeCycle-developmental-stages behavior-notable-actions ecologicalRole-ecosystem-function humanRelevance-interaction similarTaxa-reason-inclusion misconceptions-meaningful-only extraDetails-important-context style-rules-adherence direct-sentences fluff-avoidance taxonomy-repetition-avoidance technical-jargon-limitation concrete-statements-preference quality-rules-application completeness-assessment inferred-content-flag JSON-schema-strict-matching no-extra-fields no-external-commentary taxon-record-structured entomology-guide-format Agrilus-obsoletoguttatus-specific available-knowledge-integration field-support-evaluation supported-content-inclusion unsupported-content-nullification unique-content-per-field non-overlapping-information conservative-inference explicit-justification-requirement species-level-trait-caution higher-taxa-generalization-avoidance factual-accuracy-maintenance informative-content-delivery conservative-completeness-rating medium-completeness-assessment partial-reliable-data sparse-data-avoidance inferred-content-false direct-observation-reliance published-source-reliance expert-correspondence-consideration geographic-range-documentation seasonal-activity-documentation predator-prey-relationship-documentation size-comparison-documentation nest-provisioning-documentation collection-method-documentation researcher-observation-documentation Ted-MacRae-field-work Claire-Rutledge-study citizen-science-integration biosurveillance-application invasive-species-detection-context emerald-ash-borer-comparison small-size-characteristic multiple-prey-per-nest-characteristic late-spring-early-summer-activity North-American-distribution wood-boring-habit-inference host-plant-inference beech-association Fagus-inference common-name-interpretation ecological-role-inference nutrient-cycling-contribution predator-support-role human-relevance-inference indirect-surveillance-tool-support similar-species-differentiation Agrilus-quadriguttatus-comparison Agrilus-politus-comparison Agrilus-pseudofallax-comparison size-and-co-occurrence-basis misconceptions-absence extra-details-absence conservative-field-completion null-for-unsupported appearance-unsupported diet-unsupported-direct lifeCycle-unsupported-detail comprehensiveness-evaluation medium-rating-justification most-fields-well-supported-absence partial-reliable-data-presence inferred-content-flag-false direct-observation-basis no-generalization-employed strict-schema-adherence final-JSON-output-preparation review-for-compliance verification-against-rules confirmation-of-no-repetition confirmation-of-no-inference confirmation-of-no-fabrication confirmation-of-cautious-language confirmation-of-concrete-statements confirmation-of-field-focus confirmation-of-quality-assessment ready-for-output-generation
Alena minuta
Alena minuta is a species of snakefly in the family Raphidiidae, first described by Banks in 1903. The species is known from North America. Snakeflies (order Raphidioptera) are predatory insects characterized by an elongated prothorax that gives them a distinctive 'necked' appearance. As a member of the genus Alena, this species belongs to a group of small to medium-sized snakeflies.
snakefly Raphidioptera Raphidiidae predatory-insect North-America Banks-1903 small-size
Allocapnia pygmaea
Pygmy Snowfly
Allocapnia pygmaea, commonly known as the pygmy snowfly, is a small winter stonefly in the family Capniidae. It is one of the smallest members of its genus and is found across eastern and midwestern North America. As a winter stonefly, it is active during cold months when most other insects are dormant.
winter-stonefly small-size North-America cold-season-activity freshwater-streams
Allocapnia rickeri
Midwest Snowfly
Allocapnia rickeri is a small winter stonefly in the family Capniidae, commonly known as the Midwest Snowfly. It is one of numerous small, dark stoneflies in the genus Allocapnia that emerge during cold months when few other insects are active. The species has been documented across the central and eastern United States. Like other capniids, it is associated with clean, cold streams and is an important indicator of water quality.
winter-stonefly bioindicator coldwater Plecoptera Capniidae Allocapnia lotic emergence brachyptery aptery genitalia-identification Frison-1942 Midwest southeastern-US clean-water-indicator January-March small-stonefly wingless-female stream-insect shredder gatherer seasonal-resource water-quality aquatic-insect terrestrial-adult short-lived-adult oviposition submerged-eggs high-dissolved-oxygen low-temperature central-US eastern-US Alabama Arkansas Delaware Georgia Illinois hexapod hemimetabolous Euholognatha Nemouroidea Arctoperlaria Insecta Arthropoda Animalia GBIF Catalogue-of-Life iNaturalist NCBI taxonomy accepted-species 1942 Frison Ricker Midwest-Snowfly snowfly small-dark-stonefly clean-streams rivers well-oxygenated lotic-habitat cold-months winter-activity wing-reduction female-aptery male-flight epiproct paraproct terminalia taxonomic-revision congeners distribution-records observations 9-observations eukaryote metazoan arthropod insect stonefly winter-emerging January February March cold-weather near-freezing below-freezing water-surface submerged-substrates allochthonous-organic-material stream-ecosystems seasonal-food-resource insectivorous-birds predators scarce-prey unpolluted no-economic-importance stream-monitoring water-quality-indicator high-quality-coldwater microscopic-examination taxonomic-keys male-terminalia reliable-separation genitalic-examination overlapping-distribution similar-habitat small-size under-10-mm body-length reduced-wings absent-wings fully-developed-wings specific-identification published-descriptions illustrations subsequent-revisions characteristic family-Capniidae common-name extended-nymphal-period one-to-two-years short-lived does-not-feed aquatic-nymph clean-cold-streams low-temperatures year-round winter-months January-through-March family centered-Midwest extends-southeastern United-States documented appears most-reliably distinguished subtle-differences terminal-abdominal-structures should-be-compared against published subsequent genus-level characterized reduced absent females fully-developed males requires-examination male-genitalia structure paraprocts reliable separation overlaps similar many externally definitive relies microscopic examination comparison keys used biological indicator programs presence indicates cold conditions no-direct economic importance shredders gatherers processing allochthonous organic material stream ecosystems seasonal food resource insectivorous birds other when alternative prey scarce serves high-quality habitats development aquatic nymphal stages terrestrial adult stage nymphs develop streams extended period likely one two years based related species adults do-not feed active during weather air temperatures may near below freezing winged capable flight wingless short-winged remain water surface mating occur winter entering deposit eggs submerged substrates small commonly known numerous dark emerge few insects central eastern associated clean important under mm body length members genus wings possess fully developed specific identification level within requires male genitalia particularly most reliably subtle differences these terminal abdominal structures should compared descriptions taxonomic revisions winter-emerging maintain low high dissolved oxygen levels throughout year United States distribution centered extends southeastern months typically through this activity gives rise common name do not provides quality monitoring no direct habitat morphology size genitalic
Allocosa funerea
Allocosa funerea is a small wolf spider in the family Lycosidae, originally described by Hentz in 1844 under the name Lycosa funerea. The species exhibits notable sexual dimorphism in size, with females being slightly larger than males. It is primarily distributed across the eastern and central United States.
wolf-spider Lycosidae North-America small-size sexual-dimorphism
Antistea
dwarf sheet spiders
Antistea is a genus of dwarf sheet spiders in the family Hahniidae, established by Eugène Simon in 1898. The genus contains only two species: A. brunnea (Palearctic) and A. elegans (Nearctic), together forming a Holarctic distribution pattern. These spiders are among the least commonly encountered hahniids due to their small size and cryptic habits.
spiders Araneae Hahniidae dwarf-sheet-spiders comb-tailed-spiders Holarctic cryptic small-size
Antistea brunnea
Antistea brunnea is a small true spider in the family Hahniidae, commonly known as the comb-tailed spiders or dwarf sheet spiders. This species is one of the larger members of the genus Antistea and ranges across northeastern North America. It builds thin, sheet-like webs across small depressions in soil, often in mammal footprints. The species is seldom encountered due to its small size and cryptic habits.
spider Araneae Hahniidae North-America web-building cryptic small-size
Araneus pegnia
Butterfly Orbweaver
Araneus pegnia is a small orb-weaving spider in the family Araneidae, commonly known as the Butterfly Orbweaver due to the distinctive butterfly-shaped pattern on its abdomen. It is among the smaller members of the genus Araneus, with mature females reaching only 3.5–8.2 mm and males 2.5–5 mm. The species has an unusually broad geographic range, extending from the northeastern United States through the southeastern states, west to Arizona and California, and south through Middle America to Ecuador. It is also found on Caribbean islands including Jamaica, the Bahamas, and Cuba.
orbweaver small-size butterfly-pattern nocturnal autumn-activity wetland-habitat broad-distribution harmless prey-of-mud-daubers human-commensal
Araniella displicata
sixspotted orbweaver, six-spotted orbweaver
Araniella displicata, commonly known as the sixspotted orbweaver, is a small orb-weaving spider in the family Araneidae. It is one of the most widely distributed arachnids in North America, with additional populations across Europe and Asia. Adults are notably small—females reach only 4–8 mm in body length, males 4–6 mm—and are frequently mistaken for juvenile orb weavers due to their diminutive size. The species constructs compact orb webs, often spanning single leaves, and displays considerable color variation including yellow, white, and rust red.
orb-weaver Araneidae small-size color-polymorphism leaf-dwelling transcontinental-distribution
Beameria
Aridland Cicadas
Beameria is a genus of small cicadas in the family Cicadidae, comprising at least three described species. Members are among the smallest cicadas in North America, with body lengths around 16 mm. The genus is associated with prairie habitats and has been documented producing high-frequency calling songs. Beameria was established by Davis in 1934.
cicada prairie small-size high-frequency-call North-America Great-Plains conservation-concern
Beameria venosa
Aridland Cicada
Beameria venosa is one of the smallest cicada species in North America, with a body length of approximately 16 mm. It is a prairie obligate species distributed across the Great Plains from Nebraska and Colorado south to Texas and New Mexico, with additional records from Missouri, Illinois, Arkansas, and Arizona. The species produces a high-frequency calling song that is audible to humans but appears to function as a predator avoidance mechanism by being inaudible to birds and lizards. It is listed as vulnerable in Missouri due to its dependence on restricted prairie habitats.
cicada prairie small-size acoustic-communication predator-avoidance Great-Plains habitat-specialist vulnerable-species Missouri loess-hills high-frequency-calling-song endangered-ecosystem-dependent
Brachiacantha felina
Orange-spotted Lady Beetle
Brachiacantha felina is a small lady beetle in the family Coccinellidae, native to eastern and central North America. Adults measure 2.2–3 mm and exhibit distinct sexual dimorphism in pronotum coloration. The species is known from scattered records across its range, with relatively few observations documented.
Coccinellidae lady-beetle North-America sexual-dimorphism small-size
Brachiacantha indubitabilis
Small-spotted Spurleg
Brachiacantha indubitabilis is a minute lady beetle (Coccinellidae) distinguished by strong sexual dimorphism in coloration. Males display a yellow head and black pronotum with yellow anterior margin, while females have a yellowish-brown head and laterally yellow pronotum. Both sexes share black elytra marked with three yellow spots. The species is recorded from the northeastern and midwestern United States.
Coccinellidae lady-beetle sexual-dimorphism North-America small-size
Brachiacantha stephani
Stephan's lady beetle
Brachiacantha stephani, known as Stephan's lady beetle, is a small lady beetle species in the family Coccinellidae. Adults exhibit distinctive coloration with black bodies marked by yellow and reddish-orange patterns on the pronotum and elytra. The species is known from a limited geographic range in North America, specifically recorded from Arizona. It is named in honor of Karl Stephan, collector of part of the type series.
Coccinellidae lady-beetle North-America Arizona small-size sexual-dimorphism
Brachyinsara hemiptera
least katydid
Brachyinsara hemiptera, commonly known as the least katydid, is a small phaneropterine katydid species first described by Hebard in 1939. It belongs to the family Tettigoniidae and is characterized by its diminutive size compared to other katydids. The species is distributed in North America, with records from Mexico and California.
katydid Tettigoniidae Phaneropterinae North-America reduced-wings small-size
Brachysomida bivittata
Double-lined Longhorn Beetle
Brachysomida bivittata is a small longhorn beetle in the subfamily Lepturinae, commonly known as the Double-lined Longhorn Beetle. The species measures 7–11 mm in length. It occurs in Canada and the north-central United States, with Nebraska specifically documented. Three historical varieties have been described: fusciceps, nigripennis, and varians.
Cerambycidae Lepturinae longhorn-beetle North-America small-size
Brumoides septentrionis
Winter Lady Beetle
Brumoides septentrionis is a small lady beetle (Coccinellidae) native to North America. Adults measure approximately 2.9–3 mm in length. The species exhibits distinctive coloration with black markings on a yellowish-brown to red elytral background. It is known by the common name 'Winter Lady Beetle' and comprises three recognized subspecies with distinct geographic ranges across North America.
Coleoptera Coccinellidae North-America small-size subspecies-complex
Bryotropha similis
obscure neb
Bryotropha similis is a small gelechiid moth with a Holarctic distribution spanning northern Europe, Greenland, Iceland, and the Palaearctic region. The species has a wingspan of 11–13 mm and exhibits distinctive wing patterning with dark fuscous forewings and faint pale markings. Adults are active from early June to late August, likely in a single annual generation. The species is known from the iNaturalist community as the 'obscure neb'.
moth gelechiid Holarctic European-fauna small-size mountain-distribution
Calliopsis anomoptera
Strange-winged Calliopsis
Calliopsis anomoptera is a small mining bee in the family Andrenidae, described by Michener in 1942. The common name 'Strange-winged Calliopsis' refers to distinctive wing characteristics. Like other members of the genus Calliopsis, it is a ground-nesting solitary bee. The species occurs in both Central America and North America.
bee mining-bee solitary-bee ground-nesting Andrenidae pollinator red-abdomen small-size
Carmenta tildeni
Carmenta tildeni is a small clearwing moth in the family Sesiidae, described by Thomas D. Eichlin in 1995. It is native to the southwestern United States (Arizona and southern Texas) and Mexico. The species exhibits sexual dimorphism in size, with females notably smaller than males. As a member of the clearwing moth genus Carmenta, it likely possesses reduced wing scaling that creates a wasp-like appearance, though specific behavioral and ecological details remain poorly documented.
clearwing-moth sesiidae southwestern-united-states mexico small-size sexual-dimorphism 1995-description thomas-eichlin
Cerotainiops lucyae
Cerotainiops lucyae is a small robber fly (Asilidae) described by Martin in 1959. The genus Cerotainiops belongs to the tribe Cerotainiini, a group of diminutive asilids characterized by reduced wing venation and slender bodies. This species is part of a poorly studied genus with limited published biological information.
robber-fly asilidae small-size reduced-wing-venation cerotainiini
Cerotainiops mcclayi
Cerotainiops mcclayi is a species of robber fly (Family Asilidae) described by Martin in 1959. The genus Cerotainiops contains small, slender robber flies often associated with sandy or open habitats. Members of this genus are characterized by their elongated body form and reduced wing venation compared to larger asilid genera. This species is part of a group of diminutive robber flies that are frequently overlooked due to their small size and cryptic behavior.
robber-fly asilidae small-size rarely-collected taxonomically-difficult
Chaetocnema densa
Chaetocnema densa is a species of flea beetle in the family Chrysomelidae, first described by R. White in 1996. The species belongs to the genus Chaetocnema, which comprises small leaf beetles known for their jumping ability. Very little specific information is available about this particular species beyond its taxonomic description and North American distribution. Like other members of the genus, it likely feeds on plant foliage, though host associations have not been documented.
flea-beetle leaf-beetle Chrysomelidae Alticini North-America R.-White-1996 small-size underdocumented
Cisthene conjuncta
White-streaked Lichen Moth
Cisthene conjuncta is a small lichen moth in the family Erebidae, described by Barnes and McDunnough in 1913. It is restricted to southern Texas, where adults fly in March, July, and October. The species has a wingspan of approximately 15 mm. As a member of the genus Cisthene, it belongs to a group of tiger moths known for acoustic aposematism, though specific behavioral studies have not been conducted on this particular species.
endemic Texas lichen-moth small-size trimodal-flight-period
Cisthene striata
Striated Lichen Moth
Cisthene striata, described by Rodrigues Ottolengui in 1898, is a small lichen moth in the family Erebidae. It is known from a limited distribution in the eastern and central United States, with records from Maryland, Colorado, Georgia, and Florida. The species has a wingspan of approximately 17 mm. Adults have been recorded on wing year-round in Florida, suggesting continuous breeding activity in warmer portions of its range.
moth lichen-moth Erebidae North-America United-States small-size year-round-activity
Clubiona pygmaea
Pygmy Sac Spider
Clubiona pygmaea is a species of sac spider in the family Clubionidae, first described by Nathan Banks in 1892. It is distributed across the United States and Canada. As a member of the sac spider family, it likely constructs silken retreats rather than prey-capture webs and hunts actively for small prey. The species epithet "pygmaea" refers to its small size relative to other members of the genus.
sac-spider Clubionidae North-America active-hunter silken-retreat small-size
Coccinella alta
High-country Lady Beetle
Coccinella alta is a small lady beetle species in the family Coccinellidae, first described by W.J. Brown in 1962. It is native to western North America, with confirmed records from Alberta, Utah, Colorado, and California. Adults measure approximately 4.80–5.30 mm in length and display distinctive black and pale coloration patterns on the head, pronotum, and elytra. The species appears to be associated with high-elevation or montane habitats, as suggested by its specific epithet and common name.
lady-beetle Coccinellidae Coccinella western-North-America montane small-size black-and-pale-coloration 1962-description
Cochylichroa temerana
Cochylichroa temerana is a small tortricid moth native to eastern North America. The species was transferred from the genus Cochylis to the redefined genus Cochylichroa in 2019 based on phylogenetic analysis. Adults are active from early spring through mid-summer. It has been documented across a broad geographic range spanning the northeastern United States, Great Lakes region, and southeastern Canada.
tortricidae moth north-america small-size
Cononotus bryanti
Cononotus bryanti is a species of longhorned beetle in the family Cerambycidae, subfamily Cerambycinae, tribe Tillomorphini. The genus Cononotus belongs to a group of ant-mimicking cerambycids characterized by small body size and modified elytral structures. Like other members of this tribe, C. bryanti likely exhibits morphological adaptations for myrmecomorphy (ant mimicry), though specific details for this species are not well documented in available literature. The species was described by Van Dyke in 1953 and is part of the Nearctic fauna.
Cerambycidae Cerambycinae Tillomorphini ant-mimicry myrmecomorphy Nearctic small-size woodboring-beetle Van-Dyke-1953 California-fauna
Copelatus glyphicus
Copelatus glyphicus is a small diving beetle in the family Dytiscidae, described by Thomas Say in 1823. Adults measure 4.2–4.6 mm in length and 2.1–2.5 mm in width. The species is widely distributed across eastern North America.
diving-beetle North-America freshwater small-size
Corymbitodes pygmaeus
Pygmy Click Beetle
Corymbitodes pygmaeus is a diminutive click beetle species in the family Elateridae, distinguished by its exceptionally small size as indicated by its species epithet 'pygmaeus' (meaning pygmy or dwarf). The species was described by Van Dyke in 1932 and occurs across multiple Canadian provinces from British Columbia to Newfoundland. As a member of the click beetle family, it possesses the characteristic pronotal structure that enables the defensive 'clicking' mechanism used to right itself when overturned.
click-beetle pygmy small-size Canada Elateridae Van-Dyke-1932
Cosipara modulalis
Cosipara modulalis is a small crambid moth described by Eugene G. Munroe in 1972. It is known from a limited distribution in the southwestern United States, specifically Arizona and Colorado. The species has a wingspan of approximately 20 mm and appears to be active during mid-summer.
Crambidae Scopariinae moth North-America southwestern-United-States 1972-description summer-flight small-size
Cremnoptini
Cremnoptini is a tribe of parasitoid wasps within the family Braconidae. Members are small to minute wasps that parasitize the larval stages of various insects. The tribe is relatively small and understudied compared to other braconid groups. Cremnoptini wasps are characterized by reduced wing venation and compact body forms.
parasitoid braconid small-size understudied
Cyclosa conica
Conical Trashline Orbweaver
Cyclosa conica is a small orb-weaving spider known for constructing distinctive vertical webs decorated with debris. Females measure 5.3–7.5 mm in body length, while males are smaller at 3.6–4 mm. The species is recognized by its unique behavior of stringing dead insect bodies and other debris vertically through the center of its web, forming a 'trashline' or stabilimentum. The spider positions itself at the hub of this debris, relying on its cryptic coloration to blend in and avoid detection by predators. When disturbed, it feigns death as a secondary defense.
spider orb-weaver trashline camouflage stabilimentum debris-web Araneidae Cyclosa North-America Europe cryptic-coloration thanatosis predator-avoidance web-architecture small-size spring-maturation egg-sac-concealment sexual-dimorphism web-building-behavior predator-decoy
Cymodusa distincta
Cymodusa distincta is a small species of ichneumon wasp in the family Ichneumonidae. The species was described by Cresson in 1864 and has been documented in Canada, with distribution records from Edmonton and Elbow. It has been observed during blacklighting surveys in spring, suggesting nocturnal activity patterns typical of many ichneumonid wasps.
ichneumonid parasitoid nocturnal blacklight spring small-size
Dichomeris siren
Least Dichomeris Moth
Dichomeris siren is a small gelechiid moth described by Ronald W. Hodges in 1986. It is known from the eastern United States, with records spanning from the Mid-Atlantic through the Southeast and into the Midwest. The species is characterized by its diminutive size, with forewing lengths of 3.1–3.8 mm. Adults are active from late spring through early autumn.
microlepidoptera eastern-North-America small-size
Dioctria henshawi
Dioctria henshawi is a species of robber fly in the family Asilidae, first described by Johnson in 1918. The genus Dioctria belongs to the subfamily Stenopogoninae and contains small to medium-sized predatory flies. Species in this genus are among the more diminutive members of the robber fly family, typically measuring under 10 mm in length. Information regarding the specific biology and distribution of D. henshawi remains limited in available sources.
robber-fly predatory-fly small-size Stenopogoninae
Ectaetia
minute black scavenger flies
Ectaetia is a small genus of minute black scavenger flies in the family Scatopsidae. Adults are generally shiny and black, reaching up to 7 mm in length. The genus has been documented across multiple biogeographic realms including the Nearctic, Palearctic, Oriental, and Neotropical regions. Records from GBIF confirm presence in Denmark, Norway, and Sweden.
Diptera Scatopsidae minute-black-scavenger-flies shiny-black small-size widespread-distribution
Eotettix
spur-throated grasshoppers
Eotettix is a genus of spur-throated grasshoppers in the family Acrididae, established by Scudder in 1897. The genus contains approximately six described species distributed in the southeastern and south-central United States. Species within this genus are generally small grasshoppers associated with moist or wetland habitats.
grasshopper spur-throated wetland North-America Melanoplinae small-size
Eotettix pusillus
Little Eastern Grasshopper
Eotettix pusillus is a small spur-throated grasshopper in the family Acrididae. It is one of the smallest members of its genus. The species is distributed across the southeastern and south-central United States, with records from Florida, Georgia, and Oklahoma.
grasshopper spur-throated Melanoplinae small-size
Epeolus splendidus
Splendid Cellophane-cuckoo Bee
Epeolus splendidus is a cleptoparasitic (cuckoo) bee species described by Onuferko in 2018. As a member of the genus Epeolus, it invades the nests of polyester bees in the genus Colletes, where females lay eggs that hatch into larvae that kill the host egg or larva and consume the stored pollen. The species name 'splendidus' refers to its attractive appearance, characterized by short black, white, red, and yellow hairs forming distinctive patterns. Like other Epeolus species, it lacks the branched hairs typical of pollen-collecting bees due to its parasitic lifestyle.
cleptoparasite cuckoo-bee parasitic-bee Colletes-parasite Apidae Hymenoptera rare small-size colorful North-America
Eris rufa
Eris rufa is a species of jumping spider in the family Salticidae, first described by Carl Ludwig Koch in 1846 as Plexippus rufus. The species was transferred to the genus Eris in 2004 when G. B. Edwards synonymized it with the previously described Eris pinea. It occurs in northeastern North America, with documented records from Canada and the United States. The specific epithet rufa refers to the reddish coloration of this small spider, with females measuring approximately 5.9 mm and males 5.7 mm in total body length.
jumping-spider Salticidae North-America northeastern-United-States sexual-dimorphism small-size
Ethmia tricula
Ethmia tricula is a small moth species in the family Ethmiidae (Depressariidae in some classifications), described by Powell in 1973. It is endemic to California, United States. At approximately 4.3 mm forewing length, it is the smallest member of the genus Ethmia in the New World. The species is characterized by uniformly dull gray-brown wings with matching fringes.
microlepidoptera endemic California small-size
Euderces
Euderces is a genus of small longhorn beetles in the family Cerambycidae, characterized by remarkable ant-mimicry. Most species measure less than 5 mm in length and exhibit Batesian mimicry of ants, particularly species of Camponotus. The genus has its center of diversity in southern Mexico and Guatemala, with species distributed from North America through South America. Notable examples include E. velutinus, which closely resembles the tropical ant Camponotus sericeiventris. Four species occur in the United States.
ant-mimicry Batesian-mimicry Cerambycinae Tillomorphini flower-visiting wood-borer small-size New-World
Eudioctria
Eudioctria is a genus of small robber flies in the family Asilidae, established by Wilcox & Martin in 1941. The genus comprises approximately 14 described species, making it one of the more species-rich genera within the subfamily Stenopogoninae. Species in this genus are among the smallest North American robber flies, measuring only 6–8 mm in length. The genus is primarily distributed in western North America, though four species extend into eastern states.
robber-fly Asilidae Stenopogoninae small-size western-North-America
Eudioctria albius
Eudioctria albius is a small robber fly species in the family Asilidae, measuring approximately 6–8 mm in length. It is one of four Eudioctria species occurring in eastern North America, with the genus being primarily western in distribution. The species belongs to the subfamily Stenopogoninae and is among the tiniest North American robber flies.
robber-fly Asilidae Stenopogoninae small-size eastern-North-America perching-behavior
Eudioctria beameri
Eudioctria beameri is a small robber fly in the family Asilidae, subfamily Stenopogoninae. It belongs to a genus containing some of the smallest North American robber flies, with body lengths of only 6–8 mm. The species is primarily western in distribution, though some Eudioctria species extend into eastern North America. Like other robber flies, it is an active aerial predator that captures prey in flight.
robber-fly asilidae stenopogoninae predator small-size western-North-America