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Formica obscuripes
Western Thatching Ant
Formica obscuripes, the western thatching ant, is a North American mound-building ant known for constructing large thatched nests from plant materials. Colonies can contain up to 40,000 workers and demonstrate complex social organization including behavioral constancy in worker task performance. The species employs hybrid foraging strategies combining pheromone-marked columns with visual and path integration navigation. It maintains defensive mutualisms with aphids and exhibits aggressive territorial behavior including the use of formic acid against intruders and competing vegetation.
mound-building-ant thatching-ant social-insect defensive-mutualism ecosystem-engineer formic-acid behavioral-constancy hybrid-foraging North-America prairie grassland polydomy supercolony Sternorrhyncha aphid-farming visual-navigation path-integration territorial-aggression Formicidae Formicinae
Trichonephila clavata
Jorō spider, Joro Spider, Parachute spider
Trichonephila clavata, commonly known as the Jorō spider, is a large orb-weaving spider native to East Asia that has become established as an invasive species in the southeastern United States since approximately 2010. First confirmed in Georgia in 2014, it has expanded rapidly across multiple states through a combination of ballooning dispersal and human-mediated transport. The species is notable for its substantial size, striking coloration, and extensive golden webs, but poses minimal risk to humans due to small fangs and docile behavior. Its physiological adaptations—including higher metabolic rate, faster heart rate, and greater cold tolerance than its congener Trichonephila clavipes—suggest potential for continued northward range expansion.
invasive-species orb-weaver ballooning urban-wildlife biological-control cold-tolerance startle-response cannibalism kleptoparasitism Japanese-folklore Nephilidae Trichonephila spider-silk range-expansion physiological-adaptation urban-ecology agricultural-pest-predator iNaturalist Georgia Maryland East-Asia United-States spider-bite venom docile non-aggressive web-architecture egg-sac overwintering sexual-dimorphism metabolic-rate heart-rate freeze-tolerance road-ecology prey-capture competition native-spider-impacts public-perception media-sensationalism management pesticide-alternatives broom-removal ornamental structural-pest ornithology cardinal web-strength trophic-interactions DNA-metabarcoding diet-analysis species-distribution-model physiological-entomology behavioral-ecology arachnology ballooning-dispersal human-mediated-dispersal hitchhiker cargo-stowaway port-of-entry climate-change warming northward-expansion DMV Howard-County Elkridge Ilchester West-Elkridge beech-forest secondary-forest suburban roadside telephone-pole streetlamp forest-edge disturbance-tolerance prey-detection vibrational-noise auditory-disturbance motionless freezing shyness Hannibal-Lecter stink-bug lanternfly evolutionary-history ancient-association ecosystem-service biocontrol natural-enemy invasive-pest brown-marmorated-stink-bug spotted-lanternfly Halyomorpha-halys Lycorma-delicatula competitive-exclusion dominant-orb-weaver abundant population-growth rapid-spread range-span 120,000-km2 physiological-plasticity metabolism twice-as-high 77%-higher-heart-rate 74%-freeze-survival development-rate seasonal-window life-cycle-completion thermal-limitation congener-comparison natural-dispersal human-transport iNaturalist-record citizen-science confirmed-sighting breeding-population male-and-female gravid-female egg-case stowaway cargo-container port-introduction local-port vehicle-transport hitchhiking accelerated-arrival several-years natural-means prognostication prediction model suitable-habitat abundant-suitable-habitat eastern-North-America western-North-America potential-range invasive-range potential-impact environmental-impact ecological-impact ecosystem-impact monitor cautious evidence-based reasonable-journalism sensationalism exaggeration uncritical-acceptance harmless carefully-monitored next-steps research-opportunity call-for-research knowledge-gap little-known novel-ecosystem spreading rapidly-expanding invasive-predator invasive-orb-weaver non-native introduced established colonized thriving doing-fine happy merely-20-minutes-away road-trip visit access-spread beech-leaf-disease BLD state-forest remarkable-colony amongst-beech-trees confirmed-prognostication Davis-and-Frick escape-relative-warmth expand-range-northward eastern-seaboard merely-20-minutes-away-from-home resist-opportunity amazing-predators tales-of-arrival previous-episodes 2022 2024 reduce-angst large-non-native-spider establishing-in-DMV facts-presented past-episode venomous-terrible-painful Nah expert-Rick-Hoebeke risks-small puny-fangs unlikely-pierce-skin video completely-non-aggressive eastern-Howard-County haphazard-webs littered-with-remains former-victims leaves shed-exoskeletons much-larger-female dwarfs-mate positioned-just-above strand-of-silk spinnerets underside-of-abdomen near-red-mound relative-to-hand large-and-docile wait-and-see what-Jorō-means-to-ecosystems help-other-spiders put-a-beat-down-on-invasive-pests stink-bugs spotted-lanternflies passive-hunters enormous-webs larger-than-a-meter-in-diameter capture-prey-snared-in-silk arachnophobes-scary arachnophiles-beautiful important-ecosystem-services crop-pests native-range Asia having-an-old-friend-over-for-dinner reunite first-time large-spiders juicy-prey-items feathered-and-non-feathered-reptiles poses-no-known-threat difficult-to-predict-impact non-native-species experts-suggest beyond-scary-mien give-indigenous-large-orb-weavers-run-for-their-money black-and-yellow-garden-spider marbled-orb-weaver spotted-orb-weaver other-parts-of-world most-abundant-and-dominant-orb-weaver what-will-it-mean only-time-will-tell final-tidbit Jorō-shapeshifter Jorō-gumo beautiful-woman seduces-men binds-with-silk devours bad-date acknowledgements Rick-Hoebeke identifying-Jorō insights David-Coyle Bob-Bellinger great-images knowledge studies Veni-vidi-vici Nelsen-et-al.Physiological-evaluation Nephila-clavata-newly-recorded Hoebeke-et-al.Life-Cycle-Habitat-and-Variation Moore Startle-responses Davis-and-Anerao How-Urban-Tolerant-Are-They Davis-et-al.inspiration details stars Dave-Clement Miri-Talabac Maddie-Potter hooked-up-with-colony differentiate resources.ipmcenters.org link Jorō-guru David-Coyle's-take YouTube calm-your-fears Journal-of-Economic-Entomology Journal-of-Medical-Entomology chemical-management-strategies effective-management-methods spider-control-products safe-and-effective unlikely-to-bite generally-harmless big-spiders colorful-spiders invasive-spiders in-your-face-spiders webs-on-homes landscape-plants structures middle-of-where-people-live-work-and-play northern-Georgia-2014 presumed-arrived-few-years-prior 15-years increased-dramatically much-of-Southeast disjunct-populations northeastern-U.S.firestorm-of-interest rapidly-expanding-range southeastern-states many-counties Carolinas Tennessee Oklahoma more-than-a-century parts-of-Florida rarely-Pennsylvania tropics thermal-limitations higher-metabolism faster-heart-rate better-ability-to-tolerate-freezing complete-life-cycle-rapidly chilly-temperatures suite-of-adaptations expand-northward warm-loving-cousin findings-support-potential much-yet-to-be-learned successfully-survive-northern-winters nation-and-world-warm southern-species-expand higher-latitudes-and-altitudes rapidly-range-expansion-will-occur typical-mode-of-dispersal aerial-dispersal ballooning-on-strands-of-silk Charlotte's-babies Charlotte's-Web spectacular-moniker parachute-spider rain-down-from-airplanes long-distance-transit human-assistance good-hitchhikers inseminated-gravid-female egg-case-stowaway arrival-in-DMV several-years-by-natural-means new-introduction-at-local-port human-assist-in-vehicles accelerate-arrival terrible-and-painful small-fangs visited-cousin golden-silk-spider Costa-Rica exceeding-meter-diameter indigenous-large-orb-weavers run-for-their-money minimal-direct-impact firestorm Andrew-Davis Benjamin-Frick University-of-Georgia past-week native-to-eastern-Asia Japan China Korea Taiwan known-in-Georgia-since-2013 spreading-rapidly joined-its-cousin Trichonephila-clavipes established-over-160-years better-tolerate-freezing survive-northern-winters rapidly-range-expansion typical-mode long-distance new-introduction human-assist arachnophobes arachnophiles brown-marmorated-stink-bugs difficult-to-predict scary-mien indigenous-orb-weavers Mary-Nouri Sarah-Morgan WAMU relatively-harmless spider-season fall leaves-changing-color cool-crisp-autumn-air pumpkin-spice extension-entomologist Southeast not-just-spiders 20-feet-wide homes people-live-work-and-play 15-years-or-so influx-of-calls public entomology-extension-programs media-frenzy two-questions get-rid-of-Jorō-spiders are-Jorō-spiders-dangerous Clemson-University Southern-Adventist-University Washington-College Union-College two-new-studies test-methods-for-eliminating how-likely-to-bite harm scoured-internet recommended-treatment-options spider-specific-management-recommendations medically-relevant widow-spiders brown-recluses do-not-enter-homes relatively-new recommended-products labelled-spider-control-products tested-products several-products-eliminate not-legal-pesticides machine-lubricant not-recommended commercially-available strongly-encourage labelled-products easiest-and-cheapest without-chemicals broom-or-stick walked-into-spider-web rode-bike took-spider-to-face not-great-feeling wonder-if-bitey give-bitten-superpowers unique-studies evaluated-behaviors react-to-people rather-drop-off-web hang-around-and-bite really-provoke volunteered-to-get-bitten yes-you-read-correctly akin-to-mosquito-bite little-redness little-swelling largely-gone-next-day no-acquired-superpowers take-home-message twofold simplest-and-most-effective without-pesticides feel-you-need-pesticides product-labeled-for-spider-control try-not-to-freak-out doesn't-want-to-be-on-you odds-of-getting-bitten-extremely-low enjoy-glorious-fall-weather drink-pumpkin-spiced-beverage watch-where-you-walk Keep-calm-and-carry-on bites-unlikely cause-minimal-discomfort associate-professor Department-of-Forestry-and-Environmental-Conservation socials email extension featured pest-management Entomology-Today latest-posts email-subscription March-2022 wondered make-its-way-to-DMV September-2022 two-observations three-years 40-sightings happy-and-doing-just-fine several-Howard-County-locations week-or-so-ago team-of-scientists University mission killing-ultra-valuable-beech-trees thriving-amongst-beech-trees visit-amazing-predators mature-females both-Trichonephila-species three-locally-common-orb-weaving-species time-spent-immobile mild-disturbance brief-puff-of-air air-puff-response-data five-other-North-American-species published-literature 453-observations freezing-behavior 10-spider-species remained-immobile-under-a-minute both-Trichonephila-spiders over-an-hour unprecedented shyest-ever-documented tolerate-urban-environments remaining-motionless fleeing nonsexual-cannibalism mating-activity females-cannibalize-males food-availability territorial-aggression Southeastern-United-States expanding-range shy behavioral-reactions descriptive-observations photo-documentation anecdotal-observations controlled-pairings lab natural-webs field one-female-biting-and-killing-another short-fight similar-size container 25-trials fights-ensued-40%different-sizes 27-trials fights-happened-18%larger-females-not-always-aggressor 52-lab-trials six-bouts 9%direct-killing field-trials empty-web 14-trials one-fight 7%aggressor-killing-and-wrapping silk away-from-any-web not-necessarily-territoriality intraspecific-aggression provoked-or-stressed deserves-more-study newly-invasive biology physiology new-range closely-related-species successfully-established 160-years investigation compare online-records iNaturalist.org seasonal-distributions timing females physiological-traits environmental-tolerance metabolic-rates cardiac-functioning cold-exposure survival brief-below-freezing-temperature shorter-season complete-lifecycle narrow-period suitable-weather inherently-higher-metabolism low-temperature survive-better 74%-compared-to-50%brief-freeze colder-climatic-region southeastern-USA useful-information planning urban-landscapes busy-roads frequent-disturbances auditory-and-vibrational physiological-or-behavioral-changes northeast-Georgia varying-levels-of-road-traffic prey-capture-behavior simulated-prey tuning-fork 128-hz-frequency touched-to-web attacked 357-total-trials 20-different-roads attacked-59%high-variability some-roadsides-over-80%others-less-than-30%small-but-significant-negative-correlation daily-road-traffic spider-attack-rates moderate--to-heavy-traffic-roads slightly-less-likely-to-attack 51%-vs-65%able-to-live-near-roads cost-in-terms-of-prey-capture did-not-weigh-less compensate-for-disturbance accumulating-evidence human-dominated-landscapes aid-spread introduced-range Eriostethus-rufus polysphinctine-ectoparasitoid araneid-spiders Neoscona-spp.endemic-to-Japan Yamagata-Prefecture 38º46'-N northern-Japan northernmost-record genus identification-confirmed morphology DNA-barcoding cocoon large-modified-web unique inverted-triangle over-50-cm hanging-from-ill-defined-part no-organized-structure host-spider circumstantial-evidences structure-of-modified-web pre-existing-web-partly-reused orb-web-completely-removed sustaining-threads-newly-moored parasitises-host-spiders two-subfamilies unusual-for-group invasion-potential known-invasive-range review dispersal-abilities potential-impacts management-strategies October-2022 at-least-120,000-km2 South-Carolina North-Carolina Alabama West-Virginia pattern-of-spread natural-dispersal-mechanisms human-mediated-transport large-bodied-orb-weavers flying-insects small-animals thirteen-co-occurring-spider-species monitored-for-competition resources web-building-sites natural-and-urban-habitats management-options-limited advise-journalists-and-experts against-exaggerating-potential-environmental-impact ecologically-harmless rapid-spread-carefully-monitored cautious-evidence-based-approach determining-next-steps three-material-types web-capture introduced-species alter-established-trophic-interactions molecular-analysis resolve-changes community-structure foraging-links east-coast fecal-samples prey-remains-from-webs dissected-guts compare-diet-composition arthropod-targeted-COI-primers Illumina-MiSeq highest-diversity highest-richness highest-proportion-prey-reads recovery-of-prey-reads dissected-gut-content low overwhelmed-by-Jorō-spider-DNA high-proportions-Jorō-spider-reads higher-prey-diversity-and-richness detected-prey-DNA several-days-after-capture initial-gut-retention-time-estimates first-glimpse complexity-of-trophic-associations introduced-web-building-spider viable-material source-of-prey-DNA estimates-of-biodiversity Jammu-and-Kashmir northernmost-shifting document-presence behavior habitat-adaptation colder-temperature-environment Goha-Tehsil Doda-district 1556.74-meters road-bridge nearby-vegetation brightly-colored-abdomens black green yellow red long-legs yellow-and-black-bandings predominantly-seen smaller fewer unique-behaviors remaining-motionless-after-disturbances 5-10-meters-of-roads adaptation-to-human-settlements field-observations image-documentation expert-confirmation thrive-in-colder-conditions 15-20-degrees-Celsius October-November no-spider-found higher-elevations significantly-lower-temperatures adaptation-limited-to-milder-cold-regions new-insight adaptation need-for-further-research non-native-habitats eggs overwinter harsh-weather-conditions no-protection compact-silk-case milky-coating chorionic-microspheres CM fine-structural-characteristics ecological-importance uneven-size-distribution outer-eggmass evenly-covered single-layer diameter-2.3-µm short-papillary-projections segmental-adhesion mucous-components insoluble-in-water partially-soluble-in-absolute-ethanol spherical-structure HFIP strong-organic-solvent not-derived-from-vitellogenic-or-choriogenetic-processes CM-adhesive-coatings ovipositional-process equivalent-to-cocoon-silk protective-functions silken-eggcase Northern-Cardinal Cardinalis-cardinalis perches steals-food southeast-of-the-United-States questions native-fauna-affected consuming-prey-items example native-species-deriving-benefit manner-of-kleptoparasitism perched-directly-on-web supported-its-weight 42-48-g first-documented-case spider-web-supporting-perching-bird measurements force-gauge typical-webs support-masses-up-to-70-g small-but-growing-body-of-knowledge non-native-spider species-distribution-models ecological-niche-modeling predict-areas establish-if-introduced three-distinct-genetic-lineages mitochondrial-COI genome-wide-SNPs Korean-Peninsula

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