Nemertean-parasite
Guides
Pinnixa chaetopterana
tube pea crab
Pinnixa chaetopterana is a small, soft-bodied pea crab that lives symbiotically within the tubes of polychaete worms, primarily Chaetopterus variopedatus. It is a facultative commensal, occasionally free-living or associating with alternative hosts such as Amphitrite ornata. The species exhibits strong host fidelity and can distinguish conspecifics from heterospecifics. It ranges from Massachusetts to Uruguay along the western Atlantic, including Brazil and the Gulf of Mexico.
commensalsymbiosispolychaete-associationpea-crabwestern-Atlanticfacultative-symbiontcarcinonemertid-parasitehost-fidelityconspecific-recognitionzoeal-larvaetube-dwellingmarine-invertebratebrachyuran-crabpinnotheridChaetopteruszooplankton-larvamutual-intolerancepolychaete-crabnemertean-parasitesynchronous-reproduction-with-parasitecaltrop-shaped-carapacebranchial-chamber-parasitepleopod-egg-attachmenthost-tube-modificationestuarinecoastal-marinedepth-to-60mMassachusetts-to-BrazilGulf-of-MexicoFloridaNorth-CarolinaNew-JerseyUruguayStimpson-1860Tubicolixa-synonymsoft-bodied-crabwider-than-long-carapacefive-zoeal-stagesdorsal-rostral-lateral-spinesabdominal-somite-knobswing-like-knobsmedian-notch-telsonAmphitrite-ornata-alternative-hostposterior-positioning-behaviortube-aperture-bitingplankton-feedingpredator-refugeCarcinonemertes-pinnotheridophilaribbon-worm-parasitesynchronous-egg-developmenthost-parasite-egg-competitionbranchial-exoskeleton-attachmentexcurrent-canal-openingfemale-1-2-nemerteansmale-nemerteans-associatedmedial-sheath-attachmentsternum-openingnemertean-egg-sacscrab-egg-hairsfacultative-free-livingobligate-vs-facultate-commensalismhost-specificitysymbiont-recognitionheterospecific-avoidancelimb-tearing-aggressionco-occurrence-exclusionmorphological-crypsisadult-identification-difficultylarval-dispersalsettlement-behaviortube-worm-crabparchment-tube-inhabitantventilated-tube-dwellingwater-pumping-utilizationhost-turning-responsesymbiont-positioningentry-exit-hole-creationbehavioral-plasticityecological-flexibilityhost-range-expansionalternative-host-usegeographic-rangedepth-rangeAtlantic-coast-distributionwestern-hemisphere-endemicAmerican-Atlantic-faunabenthic-crustaceaninfaunal-associatesediment-tube-dwellermarine-symbiosisdecapod-brachyuraneubrachyuranthoracotremepinnotheroidpinnixinetubicolixinespecies-complex-membercryptic-species-candidatemorphological-similaritytaxonomic-revision-neededtype-locality-unknown1860-descriptionStimpson's-pea-crabhistorical-taxonomymodern-synonymyCatalogue-of-Life-synonymGBIF-Tubicolixa-matchgenus-transfer-candidatesubgeneric-classificationinfraspecific-variationsexual-dimorphism-unknownmale-gonopod-diagnosticfemale-pleopod-broodingovigerous-female-parasite-loadnemertean-prevalence-unknownincidence-data-limitedbiological-relationship-documentationsymbiont-life-history-synchronizationreproductive-timing-overlapegg-development-coordinationhatching-synchronylarval-release-coordinationpopulation-dynamics-unknowndemography-unstudiedgrowth-rate-unknownlongevity-unknownmortality-factors-unknownpredation-pressurepredator-avoidancetube-refuge-valuestructural-habitat-modificationengineering-behaviorniche-constructionhost-damagetube-wall-perforationhost-fitness-effects-unknowncommensalism-cost-benefitmutualism-possibilityparasitism-gradientsymbiosis-continuuminteraction-outcome-variabilityenvironmental-context-dependencyhost-quality-variationhost-size-correlationcrab-size-host-size-relationshipsettlement-cue-unknownlarval-settlement-behaviormetamorphosis-triggercompetency-periodpre-settlement-swimmingpost-settlement-adaptationhost-recognition-mechanismchemical-cue-usetactile-cue-usehost-tube-chemistry-detectionconspecific-chemical-detectionheterospecific-chemical-detectionaggression-triggerterritorial-behaviorresource-defensehost-monopolizationpair-formationmating-system-unknownsex-ratio-unknownoperational-sex-ratiomate-guarding-unknownsperm-competition-unknownfertilization-modeinternal-fertilizationegg-brooding-durationembryonic-development-timelarval-development-modeplanktotrophic-larvaelecithotrophy-unknownzoeal-feedingzoeal-durationmegalopa-stage-unknownsettlement-competencejuvenile-adaptationhost-tube-colonizationsubadult-behaviorsize-at-maturity-unknownmolting-frequency-unknownecdysis-in-host-tubeexuvia-disposalgrooming-behavior-unknownfeeding-mechanismsuspension-feedingfilter-feedingplankton-capturehost-current-userespiratory-current-exploitationoxygen-availabilityhypoxia-tolerancesalinity-tolerancetemperature-range-unknownphysiological-ecology-studiedoxygen-consumption-unknownmetabolic-rate-unknownenergetics-unknowngrowth-efficiency-unknownreproductive-effort-unknownfecundity-unknownegg-size-unknownoffspring-size-number-tradeoffparental-investmentmaternal-carebrooding-costparasite-load-costnemertean-reproduction-facilitationhost-egg-lossparasite-egg-competitionhatching-success-reductionfitness-consequence-unknownpopulation-level-impact-unknowncommunity-role-unknowntrophic-position-unknownenergy-flow-contributionnutrient-cycling-rolesediment-interactionbioturbation-unknownecosystem-engineering-secondaryhabitat-complexity-contributionbiodiversity-associationspecies-interaction-networkfood-web-positionpredator-unknownprey-unknowndiet-breadthtrophic-levelomnivory-unknowncarnivory-unknowndetritivory-unknownsuspension-feeding-confirmedhost-food-waste-usepseudofeces-consumption-unknownhost-mucus-usehost-tissue-consumption-unknownparasitism-unknownkleptoparasitism-unknownthievery-unknownaggression-contextintraspecific-aggressioninterspecific-aggressionlimb-autotomyregeneration-unknownwound-healingstress-responsehandling-responselaboratory-maintenancecollection-methodpreservation-effectmuseum-specimen-qualitytype-specimen-locationoriginal-description-qualitysubsequent-redescriptionstaxonomic-stabilitynomenclatural-actspriority-ruleshomonymy-checksynonymy-list-completenessdistribution-record-verificationoccurrence-data-qualityrange-boundary-uncertaintydepth-record-accuracyhabitat-description-specificityhost-record-verificationassociation-record-qualitysymbiosis-documentation-standardnatural-history-completenessresearch-priority-areasconservation-status-unknownIUCN-evaluation-neededpopulation-trend-unknownthreat-assessmenthabitat-vulnerabilityclimate-sensitivityrange-shift-potentialphenology-changehost-phenology-dependencyphenological-mismatch-riskevolutionary-history-unknownphylogenetic-positionsister-species-unknownspecies-group-membershipgenetic-differentiationcryptic-diversity-potentialbarcode-library-coveragegenome-resourcestranscriptome-unknownproteome-unknownmetabolome-unknowndevelopmental-genetics-unknownsymbiosis-genetics-unknownhost-recognition-gene-unknownimmune-response-unknownparasite-resistance-unknowncoevolution-historyphylogeography-unknownpopulation-structure-unknowngene-flow-unknowndispersal-limitationisolation-by-distancelocal-adaptation-unknownphenotypic-plasticitymorphological-variationenvironmental-gradient-responsephenotypic-clinegenotype-environment-interactionevolutionary-potentialadaptive-capacityresilience-unknownextinction-risk-assessment-neededRandallia ornata
globose sand crab, purple globe crab
Randallia ornata is a true crab in the family Leucosiidae, commonly known as the globose sand crab or purple globe crab. It inhabits sandy beaches along the eastern Pacific coast from Northern California to Baja California, Mexico. The species is notable as a host for an undescribed nemertean worm in the genus Carcinonemertes, which acts as an egg predator with infection rates reaching 70% in crab populations.