Cirsium
Guides
Hadroplontus litura
Canada thistle stem weevil, minute seed weevil
Hadroplontus litura is a stem-mining weevil in the family Curculionidae, widely known as the Canada thistle stem weevil. It is an endophagous herbivore that develops within the stems of its host plants. The species has been investigated extensively as a biological control agent for the invasive weed Canada thistle (Cirsium arvense). Research indicates it can complete its life cycle on multiple Cirsium species, including five native thistle species in the upper Midwest of North America, raising concerns about non-target impacts on native flora.
Narnia femorata
Leaf-footed Cactus Bug
Narnia femorata is a leaf-footed bug (Coreidae) native to the southern United States and Central America. The species was introduced to Florida in the 1960s via nursery stock and is now fully established. It feeds primarily on cactus fruit, especially Opuntia species, using a long tube-like beak. Males possess enlarged, spiny hind femora used as weapons in male-male combat for territories on cactus pads bearing fruit. The species exhibits pronounced phenotypic plasticity, with body size, weapon size, and beak length changing seasonally in response to host plant fruit availability. Populations have been documented utilizing Cirsium thistle as an alternative host, representing a recent host range expansion.
Paracantha gentilis
Paracantha gentilis is a tephritid fruit fly species described by Hering in 1940 from Wyoming specimens. The species has a complex taxonomic history, with several taxa described by Malloch in 1941 (mimetica, mimetica elongata, mexicana) and Aczél in 1953 (sobrina) later synonymized under P. gentilis when wing pattern variation proved continuous rather than discrete. It is the first Tephritidae species in which the median oral lobe of larvae was described, a character now known to be shared by all non-frugivorous Tephritinae. The species exhibits a bivoltine life cycle with distinct behavioral and morphological adaptations for exploiting Cirsium thistle flowerheads.
Trichosirocalus
rosette weevils, crown weevils
A genus of small true weevils native to the Palearctic region. Several species have been widely introduced to North America, Australia, and New Zealand as biological control agents for invasive thistles. The genus was historically treated as containing a single species, T. horridus, but integrative taxonomic studies using molecular and morphological data have revealed multiple distinct species with different host associations.
weevilbiological-controlthistleinvasive-species-managementCeutorhynchinaerosette-feederCeutorhynchiniBaridinaetaxonomic-revisionclassical-biological-controlCarduusCirsiumOnopordumPalearctic-nativeintroduced-speciesmolecular-systematicsintegrative-taxonomyunivoltineleaf-mineragricultural-pest-controlpasture-weed-managementspecies-complexhost-specificitymusk-thistleplumeless-thistleScotch-thistleIllyrian-thistlewelted-thistleItalian-thistlecrown-weevilrosette-weeviloviposition-behavioroverwinteringegg-stagelarval-stageadult-stagedecaying-organic-mattersoil-surfacenon-photosynthetic-leavesgreen-leavesleaf-midribspetiolesleaf-miningnotching-damagerosette-survivalflowering-stem-reductionseed-production-reductionrosette-mortalitypopulation-density-effectsmark-recapturedispersal-patternsartificial-diet-rearinglaboratory-culturevitamin-supplementationlyophilized-thistle-rootsergosterolcasein-hydrolysate7-dehydrocholesterolsucroselarval-survivaladult-longevityovipositionfemale-fecundityfield-cage-experimentsindividual-cage-experimentsgrowth-parameter-reductionpre-release-host-specificity-testingpost-release-monitoringestablishment-successrange-expansionforested-areasagricultural-landpasturesmall-farmscropsdisturbed-habitatsmeadowsdense-patchesrosette-size-preferencespatial-distributionselective-ovipositionautumn-egg-layingwinter-larval-developmentspring-pupationlate-summer-adult-emergencesoil-overwinteringplant-debris-overwinteringrachisleaf-dissectiondestructive-samplingnon-destructive-samplingsampling-biaslife-stage-detectionestablished-populationsmitochondrial-COInuclear-EF-1αmorphological-charactershost-plant-associationssynonymyspecies-validityintroduction-historyrelease-recordsestablishment-recordsOld-World-nativeNew-World-introductionSouthern-Hemisphere-introductionAustraliaNew-ZealandNorth-AmericaVirginiaSouthwest-VirginiaEuropeSpainFranceGermanyItalySwitzerlandAustriaScandinaviaDenmarkNorwaySwedenColonnelli-1979Panzer-1801Alonso-Zarazaga-&-Sánchez-Ruiz-2002Ceutorhynchinae-vs-Baridinaesubfamily-placementtribe-placementtrue-weevilsCurculionidaeColeopteraInsectaArthropodaAnimalia882-iNaturalist-observationsGBIF-recordsCatalogue-of-Life-acceptedNCBI-TaxonomyBulletin-of-Entomological-ResearchJournal-of-Applied-EcologyJournal-of-Entomological-ScienceAnnals-of-the-Entomological-Society-of-AmericaEnvironmental-EntomologyDOI-10.1017/s000748531500084xDOI-10.1046/j.1365-2664.2002.00747.xDOI-10.18474/0749-8004-22.4.324DOI-10.18474/0749-8004-22.4.330DOI-10.18474/0749-8004-24.4.465DOI-10.1093/aesa/73.6.694DOI-10.1093/ee/10.5.691