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Echidnophaga gallinacea
hen flea, sticktight flea, stickfast flea
Echidnophaga gallinacea is a small, dark brown flea that parasitizes a broad range of bird and mammal hosts including poultry, dogs, cats, and occasionally humans. Adult females embed permanently into host skin—typically on bare areas of the head and face—using a serrated mouthpart to feed on blood, while males remain mobile. Heavy infestations cause ulceration, dermatitis, anemia, and can be fatal to young or small hosts. The species has spread globally through poultry farming and is now established across tropical, subtropical, and temperate regions.
flea ectoparasite poultry-pest vector invasive cosmopolitan integrated-pest-management cage-free-poultry backyard-chickens hematophagy permanent-attachment sessile-female resilin jumping ctenidia-absent anaemia dermatitis ulceration Rickettsia Bartonella plague diatomaceous-earth maldison pesticide-resistance organic-farming animal-welfare economic-entomology veterinary-entomology host-generalist urban-wildlife-interface synanthropic
Pulex irritans
Human Flea, House Flea
Pulex irritans is a cosmopolitan flea species commonly known as the human flea. Despite its name, it has a broad host range including humans, dogs, cats, livestock, and various wild mammals. The species is thought to have originated in South America, possibly associated with guinea pigs or peccaries as original hosts. It is one of only six species in the genus Pulex, with the other five restricted to Nearctic and Neotropical regions. P. irritans has been found in human archaeological sediments dating back thousands of years in Europe and Greenland, demonstrating its long association with human populations. The species is medically significant as a potential vector of plague (Yersinia pestis), murine typhus, trench fever (Bartonella quintana), flea-borne spotted fever (Rickettsia felis), and the tapeworm Dipylidium caninum.
flea vector plague cosmopolitan hematophagy zoonosis cryptic-species climate-change archaeological-record One-Health
Stictocephala stimulea
Stictocephala stimulea is a treehopper species in the family Membracidae, first described by Van Duzee in 1914. Treehoppers in this genus are characterized by their enlarged, often ornate pronotum that extends over the body like a helmet or thorn. The specific epithet 'stimulea' suggests possible resemblance to or association with stinging organisms, though this refers to appearance rather than actual sting. Like other membracids, this species likely feeds on plant phloem sap using piercing-sucking mouthparts.
Membracidae treehopper Auchenorrhyncha Cicadomorpha Stictocephala Ceresini Smiliinae Hemiptera sap-feeder pronotum helmet thorn-mimicry plant-feeding-insect phloem-feeder cryptic-coloration camouflage Van-Duzee-1914 Nearctic North-America Florida North-Carolina South-Dakota understudied-species data-deficient taxonomy entomology insect arthropod true-bug auchenorrhynchan cicadomorph leafhopper-relative plant-hopper ornate-pronotum pronotal-extension dorsal-helmet insect-morphology insect-systematics biodiversity natural-history conservation insect-ecology insect-behavior insect-development insect-distribution biogeography species-description type-specimen original-description historical-taxonomy museum-specimen collection-record occurrence-data GBIF iNaturalist citizen-science observation-record range-map distribution-data geographic-range endemic native-species regional-fauna local-biodiversity habitat-specificity host-plant feeding-guild phytophagous herbivore plant-insect-interaction coevolution mimicry defense crypsis evolutionary-adaptation morphological-adaptation exoskeleton-modification structural-coloration insect-identification field-guide diagnostic-character taxonomic-key species-complex cryptic-species morphological-variation geographic-variation phenotypic-plasticity life-history reproduction oviposition nymph instar metamorphosis hemimetabolous incomplete-metamorphosis population-dynamics community-ecology food-web trophic-level primary-consumer ecosystem-function nutrient-cycling energy-flow biological-control pest-status agricultural-relevance forestry urban-ecology invasive-potential climate-change habitat-loss conservation-status data-gap research-need taxonomic-revision phylogenetics molecular-systematics DNA-barcoding integrative-taxonomy natural-history-collection specimen-digitization open-data FAIR-data biodiversity-informatics biological-database taxonomic-authority nomenclature zoological-nomenclature International-Code-of-Zoological-Nomenclature type-locality type-specimen-deposition author-citation original-combination current-combination synonymy homonymy nomenclatural-act taxonomic-history classification-system phylogenetic-classification evolutionary-relationships monophyly clade lineage stem-group crown-group divergence-time molecular-clock fossil-record paleontology extant extinct living-fossil evolutionary-history biogeographic-history dispersal vicariance range-expansion range-contraction refugium glacial-relict postglacial-colonization anthropogenic-impact human-disturbance land-use-change urbanization agricultural-intensification pesticide-use habitat-fragmentation connectivity corridor protected-area conservation-planning systematic-conservation-planning priority-area hotspot endemic-area center-of-origin center-of-diversity evolutionary-significant-unit management-unit population metapopulation source-sink-dynamics demography vital-rates survival fecundity generation-time population-growth-rate carrying-capacity density-dependence regulation limiting-factor environmental-stochasticity demographic-stochasticity genetic-stochasticity inbreeding-depression outbreeding-depression genetic-diversity heterozygosity allelic-richness effective-population-size genetic-drift gene-flow migration isolation-by-distance isolation-by-resistance landscape-genetics population-genomics phylogeography historical-demography coalescent-theory approximate-Bayesian-computation species-distribution-model ecological-niche-model habitat-suitability bioclimatic-envelope climate-envelope niche-conservatism niche-evolution realized-niche fundamental-niche biotic-interaction competition predation parasitism mutualism commensalism amensalism facilitation apparent-competition indirect-interaction trophic-cascade top-down-control bottom-up-control mesopredator-release keystone-species ecosystem-engineer foundation-species dominant-species characteristic-species indicator-species umbrella-species flagship-species surrogate-species focal-species target-species pest-species invasive-species naturalized-species alien-species non-native-species introduced-species cryptogenic-species range-shift poleward-shift elevational-shift phenological-shift temporal-mismatch trophic-mismatch phenology seasonality voltinism univoltine bivoltine multivoltine partial-generation prolonged-diapause aestivation hibernation overwintering overwintering-strategy cold-hardiness freeze-tolerance freeze-avoidance supercooling cryoprotectant thermal-biology thermoregulation behavioral-thermoregulation microclimate-selection habitat-selection oviposition-site-selection host-selection mate-choice sexual-selection sperm-competition cryptic-female-choice reproductive-isolation prezygotic-isolation postzygotic-isolation speciation allopatric-speciation sympatric-speciation parapatric-speciation peripatric-speciation reinforcement hybridization introgression hybrid-zone cline ecotone contact-zone secondary-contact exogenous-selection endogenous-selection ecological-speciation mutation-order-speciation sexual-conflict sexual-dimorphism sexual-size-dimorphism sexual-dichromatism polymorphism color-polymorphism morph phase gregarious-phase solitary-phase density-dependent-polyphenism reaction-norm genotype-environment-interaction plasticity canalization genetic-assimilation acclimation acclimatization hardening stress-response heat-shock-protein oxidative-stress hypoxia desiccation starvation immune-response innate-immunity humoral-immunity cellular-immunity encapsulation nodulation phagocytosis melanization antimicrobial-peptide phenoloxidase prophenoloxidase lysozyme defensin cecropin diptericin attacin immune-gene immune-pathway Toll-pathway Imd-pathway JAK-STAT-pathway NF-κB relish dorsal immune-memory specific-immunity transgenerational-immune-priming gut-microbiome symbiosis obligate-symbiont facultative-symbiont primary-symbiont secondary-symbiont vertical-transmission horizontal-transmission mixed-mode-transmission nutritional-symbiosis defensive-symbiosis digestive-symbiosis detoxification metabolism biosynthesis vitamin-synthesis amino-acid-synthesis steroid-synthesis cuticle-synthesis chitin-synthesis molting ecdysis ecdysteroid juvenile-hormone insulin-signaling TOR-signaling nutrient-sensing energy-storage lipid-metabolism carbohydrate-metabolism protein-metabolism flight-metabolism respiration tracheal-system spiracle gas-exchange water-balance osmoregulation excretion Malpighian-tubule hindgut rectum cryptonephridial-system ion-transport water-reabsorption nitrogenous-waste uric-acid urea ammonia detoxification-enzyme cytochrome-P450 glutathione-S-transferase carboxylesterase mixed-function-oxidase resistance insecticide-resistance acaricide-resistance herbicide-resistance antibiotic-resistance resistance-management resistance-evolution resistance-mechanism target-site-resistance metabolic-resistance behavioral-resistance cuticular-resistance resistance-allele resistance-gene fitness-cost fitness-benefit pleiotropy trade-off life-history-trade-off allocation resource-allocation energy-allocation time-allocation foraging optimal-foraging central-place-foraging patch-use marginal-value-theorem predator-avoidance antipredator-defense masquerade Batesian-mimicry Müllerian-mimicry automimicry intraspecific-mimicry intersexual-mimicry aggressive-mimicry social-parasitism brood-parasitism kleptoparasitism defense-behavior thanatosis death-feigning startle-display deimatic-display eyespot deflection-mark autotomy reflex-bleeding regurgitation defensive-secretion venom toxin allomone kairomone synomone semiochemical pheromone sex-pheromone aggregation-pheromone alarm-pheromone trail-pheromone territorial-pheromone recognition-pheromone signature-mixture cuticular-hydrocarbon volatile-organic-compound olfaction gustation mechanoreception thermoreception hygroreception photoreception vision compound-eye ommatidium rhabdom visual-pigment opsin color-vision polarization-vision motion-detection optomotor-response phototaxis photoperiodism circadian-rhythm biological-clock entrainment zeitgeber circannual-rhythm photoperiod day-length critical-day-length critical-photoperiod diapause-induction diapause-termination diapause-maintenance diapause-development endocrine-control neuroendocrine corpus-allatum corpus-cardiacum prothoracic-gland ecdysiotropin ecdysiostatin allatostatin allatotropin neuropeptide hormone hormone-receptor signal-transduction gene-expression transcription-factor regulatory-gene structural-gene gene-network gene-regulatory-network developmental-gene Hox-gene homeobox segment-polarity-gene gap-gene pair-rule-gene maternal-effect-gene zygotic-gene embryonic-development embryogenesis cleavage blastoderm gastrulation segmentation tagmosis appendage-development imaginal-disc holometabolous complete-metamorphosis larva pupa adult apolysis teneral sclerotization tanning cuticle exoskeleton epicuticle procuticle exocuticle endocuticle resilin sclerotin chitin protein lipid wax cement-layer wax-layer surface-lipid waterproofing anti-wetting anti-fouling self-cleaning structural-color pigmentary-color ommin pteridine carotenoid melanin papiliochrome flavonoid anthocyanin betalain iridescence photonic-crystal diffraction-grating thin-film-interference multilayer-reflector scattering Tyndall-scattering Rayleigh-scattering Mie-scattering non-iridescent-structural-color biochrome biofluorescence bioluminescence luciferin luciferase photoprotein bioluminescent-system counter-illumination burglar-alarm lure communication mate-recognition predator-deterrence aposematism warning-coloration honest-signal dishonest-signal signal-evolution signal-design receiver-psychology sensory-bias sensory-exploitation sensory-trap amplifier attenuator signal-efficacy signal-honesty handicap-principle index-signal conventional-signal assessment-signal territorial-signal dominance-signal submissive-signal aggressive-signal courtship-signal copulatory-signal postcopulatory-signal antagonistic-coevolution chase-away-selection sensory-drive reproductive-character-displacement genetic-exchange admixture hybrid-fitness hybrid-breakdown hybrid-vigor heterosis genetic-load mutational-meltdown founder-effect bottleneck population-expansion invasion-genetics propagule-pressure introduction-effort establishment spread lag-phase exponential-growth logistic-growth Allee-effect demographic-Allee-effect component-Allee-effect strong-Allee-effect weak-Allee-effect critical-population-size minimum-viable-population extinction-risk population-viability-analysis stochastic-model deterministic-model individual-based-model agent-based-model spatially-explicit-model metapopulation-model source-sink-model integrated-population-model state-space-model hierarchical-model Bayesian-model machine-learning artificial-intelligence computer-vision image-recognition automated-identification deep-learning neural-network convolutional-neural-network transfer-learning data-augmentation training-set validation-set test-set accuracy precision recall F1-score confusion-matrix receiver-operating-characteristic area-under-curve model-selection model-validation cross-validation bootstrapping permutation-test null-model randomization-test Monte-Carlo-simulation Markov-chain-Monte-Carlo Gibbs-sampling Metropolis-Hastings-algorithm Bayesian-inference prior-distribution posterior-distribution likelihood-function evidence model-comparison Bayes-factor information-criterion Akaike-information-criterion corrected-AIC Bayesian-information-criterion deviance-information-criterion Watanabe-Akaike-information-criterion cross-validation-information-criterion stacking model-averaging ensemble-model prediction forecasting scenario-analysis sensitivity-analysis uncertainty-analysis propagation-of-uncertainty error-budget confidence-interval credible-interval prediction-interval tolerance-interval statistical-power sample-size effect-size significance-test hypothesis-testing null-hypothesis alternative-hypothesis type-I-error type-II-error false-positive false-negative multiple-comparison Bonferroni-correction false-discovery-rate q-value p-value significance-level alpha-level beta-level statistical-test parametric-test nonparametric-test robust-test exact-test asymptotic-test bootstrap-test jackknife resampling subsampling leave-one-out k-fold stratified-sampling balanced-sampling imbalanced-data class-imbalance oversampling undersampling synthetic-minority-oversampling SMOTE ADASYN cost-sensitive-learning ensemble-method bagging boosting random-forest gradient-boosting XGBoost LightGBM CatBoost support-vector-machine kernel-method radial-basis-function polynomial-kernel linear-kernel sigmoid-kernel decision-tree classification-tree regression-tree pruning cost-complexity-pruning minimum-description-length rule-based-classifier association-rule frequent-pattern apriori-algorithm FP-growth sequential-pattern temporal-pattern spatial-pattern spatiotemporal-pattern time-series-analysis trend-analysis seasonal-decomposition autoregressive-model moving-average-model ARIMA SARIMA exponential-smoothing state-space-model Kalman-filter particle-filter hidden-Markov-model dynamic-Bayesian-network recurrent-neural-network long-short-term-memory gated-recurrent-unit transformer attention-mechanism self-attention multi-head-attention encoder decoder encoder-decoder-architecture sequence-to-sequence-model generative-model generative-adversarial-network variational-autoencoder normalizing-flow diffusion-model energy-based-model Boltzmann-machine restricted-Boltzmann-machine deep-belief-network autoencoder denoising-autoencoder sparse-autoencoder contractive-autoencoder variational-inference expectation-maximization maximum-likelihood maximum-a-posteriori maximum-entropy Occam's-razor parsimony model-complexity overfitting underfitting bias-variance-tradeoff regularization L1-regularization L2-regularization elastic-net dropout early-stopping batch-normalization layer-normalization group-normalization instance-normalization weight-decay mixup cutout cutmix random-erasing autoaugment fast-autoaugment population-based-augmentation neural-architecture-search automated-machine-learning hyperparameter-optimization grid-search random-search Bayesian-optimization sequential-model-based-optimization multi-fidelity-optimization knowledge-distillation teacher-student-model model-compression quantization knowledge-transfer domain-adaptation few-shot-learning zero-shot-learning one-shot-learning meta-learning learning-to-learn metric-learning siamese-network triplet-loss contrastive-learning self-supervised-learning unsupervised-learning semi-supervised-learning weakly-supervised-learning active-learning online-learning incremental-learning continual-learning lifelong-learning curriculum-learning multi-task-learning multi-modal-learning cross-modal-learning representation-learning feature-learning embedding-learning manifold-learning dimensionality-reduction principal-component-analysis t-SNE UMAP word-embedding sentence-embedding document-embedding knowledge-graph-embedding graph-neural-network graph-convolutional-network graph-attention-network message-passing-neural-network relational-graph-convolutional-network inductive-learning transductive-learning homophily heterophily graph-isomorphism Weisfeiler-Lehman-test subgraph-isomorphism graph-matching network-alignment network-embedding node-embedding edge-embedding graph-classification node-classification link-prediction graph-generation graph-synthesis molecular-generation de-novo-design inverse-design retrosynthesis reaction-prediction property-prediction quantitative-structure-activity-relationship QSAR quantitative-structure-property-relationship QSPR molecular-descriptor fingerprint Morgan-fingerprint extended-connectivity-fingerprint circular-fingerprint atom-pair-fingerprint topological-torsion-fingerprint pharmacophore shape-similarity electrostatic-similarity docking scoring-function binding-affinity-prediction protein-ligand-interaction protein-protein-interaction protein-structure-prediction AlphaFold protein-folding contact-prediction distance-prediction angle-prediction torsion-prediction secondary-structure-prediction tertiary-structure-prediction quaternary-structure-prediction protein-design protein-engineering directed-evolution rational-design computational-design de-novo-protein-design enzyme-design catalytic-antibody ribozyme aptamer DNAzyme synthetic-biology genetic-circuit metabolic-engineering metabolic-flux-analysis flux-balance-analysis genome-scale-metabolic-model dynamic-metabolic-model kinetic-modeling stoichiometric-modeling constraint-based-modeling optimization linear-programming mixed-integer-linear-programming quadratic-programming nonlinear-programming dynamic-programming stochastic-programming robust-optimization multi-objective-optimization Pareto-optimality evolutionary-algorithm genetic-algorithm genetic-programming differential-evolution particle-swarm-optimization ant-colony-optimization simulated-annealing tabu-search variable-neighborhood-search iterated-local-search greedy-randomized-adaptive-search scatter-search path-relinking memetic-algorithm hyper-heuristic metaheuristic local-search neighborhood-search hill-climbing random-walk randomized-search Monte-Carlo-tree-search upper-confidence-bound Thompson-sampling multi-armed-bandit contextual-bandit reinforcement-learning policy-gradient actor-critic Q-learning deep-Q-network policy-iteration value-iteration temporal-difference-learning SARSA expected-SARSA double-Q-learning dueling-Q-network prioritized-experience-replay distributed-reinforcement-learning impala A3C asynchronous-advantage-actor-critic PPO proximal-policy-optimization TRPO trust-region-policy-optimization DDPG deep-deterministic-policy-gradient TD3 twin-delayed-deep-deterministic-policy-gradient SAC soft-actor-critic model-based-reinforcement-learning model-predictive-control guided-policy-search imitation-learning inverse-reinforcement-learning apprenticeship-learning behavior-cloning dataset-aggregation DAgger generative-adversarial-imitation-learning third-person-imitation-learning one-shot-imitation-learning meta-reinforcement-learning hierarchical-reinforcement-learning option skill subgoal intrinsic-motivation curiosity-driven-exploration empowerment information-gain prediction-error novelty-seeking diversity-seeking multi-agent-reinforcement-learning mean-field fictitious-play correlated-equilibrium Nash-equilibrium game-theory mechanism-design auction-theory incentive-design social-choice-theory voting-theory fair-division matching-theory market-design algorithmic-game-theory computational-social-choice computational-complexity NP-completeness NP-hardness approximation-algorithm approximation-ratio inapproximability fixed-parameter-tractability parameterized-complexity kernelization treewidth graph-minor forbidden-minor-characterization well-quasi-ordering Robertson-Seymour-theorem graph-structure-theorem bidimensionality-theory meta-theorem Courcelle's-theorem automata-theory finite-automaton pushdown-automaton Turing-machine computability decidability halting-problem Rice's-theorem Gödel's-incompleteness-theorems lambda-calculus combinatory-logic type-theory proof-theory model-theory set-theory forcing large-cardinal axiom-of-choice continuum-hypothesis independence-result consistency-strength reverse-mathematics constructive-mathematics intuitionistic-logic modal-logic temporal-logic epistemic-logic deontic-logic description-logic ontology knowledge-representation semantic-web linked-data RDF SPARQL OWL knowledge-graph entity-linking relation-extraction event-extraction coreference-resolution named-entity-recognition part-of-speech-tagging dependency-parsing constituency-parsing semantic-parsing natural-language-inference textual-entailment natural-language-generation machine-translation summarization question-answering dialogue-system conversational-AI chatbot virtual-assistant speech-recognition speech-synthesis speaker-recognition emotion-recognition sentiment-analysis opinion-mining aspect-based-sentiment-analysis target-dependent-sentiment-analysis stance-detection rumor-detection fake-news-detection fact-checking claim-verification evidence-retrieval argument-mining persuasion-detection deception-detection personality-prediction mental-health-detection suicide-prevention crisis-intervention social-media-mining network-analysis community-detection influence-maximization information-diffusion cascade-modeling epidemic-modeling SEIR-model SIR-model agent-based-epidemic-model compartmental-model network-epidemic-model metapopulation-epidemic-model spatial-epidemic-model stochastic-epidemic-model branching-process renewal-equation generation-interval serial-interval incubation-period latent-period infectious-period basic-reproduction-number effective-reproduction-number herd-immunity-threshold vaccination-coverage vaccine-efficacy vaccine-effectiveness breakthrough-infection waning-immunity immune-escape variant-of-concern variant-of-interest variant-under-monitoring phylogenetic-analysis molecular-clock-analysis phylodynamics viral-evolution antigenic-drift antigenic-shift zoonotic-spillover reservoir-host intermediate-host amplifying-host dead-end-host vector-borne-disease mosquito-borne-disease tick-borne-disease flea-borne-disease lice-borne-disease midge-borne-disease sandfly-borne-disease tsetse-borne-disease blackfly-borne-disease triatomine-borne-disease kissing-bug Chagas-disease trypanosomiasis leishmaniasis malaria dengue yellow-fever Zika-virus chikungunya West-Nile-virus Japanese-encephalitis tick-borne-encephalitis Lyme-disease Rocky-Mountain-spotted-fever ehlichiosis anaplasmosis babesiosis tularemia plague murine-typhus epidemic-typhus endemic-typhus scrub-typhus Q-fever trench-fever bartonellosis cat-scratch-disease rat-bite-fever leptospirosis brucellosis anthrax melioidosis glanders tularaemia francisellosis coxiellosis rickettsiosis orientia-infection ehrlichiosis neoehrlichiosis neorickettsiosis anaplasmataceae rickettsiaceae coxiellaceae bartonellaceae brucellaceae francisellaceae pasteurellaceae legionellaceae chlamydiaceae mycoplasmataceae ureaplasmataceae spiroplasmataceae achaenoplasmataceae entomoplasmataceae haloplasmataceae tenericutes mollicutes bacteroidetes fusobacteria spirochaetes synergistetes deferribacteres thermotogae aquificae caldiserica caldithrix deferrisoma desulfurobacterium thermovibrio thermocrinis hydrogenobacter sulfurihydrogenibium persephonella hydrogenobaculum hydrothermus thermothrix sulfuricurvum sulfurimonas sulfurovum thiovulum thiomicrospira pseudomonas vibrio aeromonas photobacterium aliivibrio gracilibacillus halobacillus halomonas chromohalobacter cobetia salinicola kushneria halotalea halovibrio salinivibrio thioalkalivibrio thiohalophilus ectothiorhodospira halorhodospira thiorhodospira halochromatium thioflavicoccus marichromatium thiocapsa lamprocystis thiodictyon thiopedia amoebobacter thiocystis chromatium allo-chromatium thermochromatium rhabdochromatium thiobaca thiohalocapsa halocapsa thiolamprovum thioploca thiomargarita beggiatoa methylococcus methylomonas methylomicrobium methylosinus methylocystis methylocella methylocapsa methylacidiphilum verrucomicrobia planctomycetes chlamydiae lentisphaerae kiritimatiellaeota calditrichaeota fervidibacteria

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