Brachyura

Guides

Achelous
Achelous is a genus of swimming crabs in the family Portunidae, established by De Haan in 1833. These marine brachyuran crabs are characterized by their flattened, streamlined bodies and modified fifth pereiopods adapted for swimming. The genus includes commercially significant species such as A. spinimanus, a fishery resource in southeastern Brazil, and A. hastatus, distributed across the Atlantic-Mediterranean region. Species within this genus exhibit habitat preferences related to sediment type and depth, with some showing age and sexual segregation patterns typical of portunid crabs.
Portunidae swimming-crab marine Decapoda Brachyura fishery-resource benthic nocturnal-forager
Cancer irroratus
Atlantic rock crab, peekytoe crab
A medium-sized marine crab native to the western North Atlantic, ranging from Iceland to South Carolina. Adults reach 133 mm carapace width and can live up to 8 years. The species occupies depths from intertidal zones to 790 m. It has become commercially significant as the 'peekytoe crab' and has established non-native populations in Iceland via ballast water transport.
marine commercial-fishery invasive-potential rocky-habitat decapod brachyura north-atlantic ballast-water-introduction lobster-interaction peekytoe-crab
Leucosiidae
Purse Crabs
Leucosiidae is a family of marine crabs commonly known as purse crabs. The family contains three subfamilies and several genera of uncertain placement. Members are characterized by their rounded, often smooth carapaces that resemble small purses or pebbles. The family was established by George Samouelle in 1819.
crab marine decapod brachyura
Ovalipes
paddle crab, lady crab, three-spot swimming crab
Ovalipes is a genus of swimming crabs in the family Ovalipidae, established by Mary J. Rathbun in 1898. The genus comprises approximately 12 extant species distributed across marine coastal waters of the Pacific, Atlantic, and Indian Oceans. Several species hold commercial importance, particularly O. punctatus in East Asian fisheries and O. catharus in New Zealand. Members exhibit characteristic portunid adaptations for swimming, including flattened, paddle-shaped fifth pereiopods.
decapoda brachyura swimming-crab paddle-crab commercial-fishery sound-production temperate-marine benthic-predator
Pachygrapsus transversus
Mottled Shore Crab
A small to medium-sized shore crab native to the western Atlantic, ranging from the eastern United States through the Caribbean and Gulf of Mexico to Brazil. The species inhabits rocky and hard substrates in intertidal zones, where it is commonly found in crevices and under rocks. Reproductive studies indicate it breeds in the Brazilian temperate zone, with specific population dynamics documented in that region. The species serves as a host for multiple parasites including the bopyrid isopod Leidya bimini and the rhizocephalan barnacle Sacculina carcini.
shore-crab intertidal western-Atlantic parasite-host Grapsidae Brachyura decapod crustacean
Panopeus
mud crabs
Panopeus is a genus of mud crabs in the family Panopeidae, distributed primarily in intertidal and estuarine environments of the Western Atlantic. Species within this genus exhibit sexual size dimorphism, with males typically larger than females, and show specialized habitat use patterns including vertical stratification within reef structures. Some species demonstrate extreme male-biased sexual size dimorphism driven by sexual antagonistic coevolution and coercive mating systems. Members of this genus are ecosystem engineers in mangrove and estuarine habitats, influencing sediment structure and energy flow.
Brachyura Panopeidae mud-crab intertidal estuarine oyster-reef sexual-dimorphism habitat-partitioning Western-Atlantic mangrove ecosystem-engineer
Panopeus lacustris
knot-fingered mud crab
Panopeus lacustris, commonly known as the knot-fingered mud crab, is a small true crab (infraorder Brachyura) in the family Panopeidae. It is distinguished by unequal-sized chelae, with the larger claw being exceptionally broad, knobbly, and bearing teeth in the molar area with an immobile finger. The species exhibits sexual dimorphism in size, with males typically larger than females. It is native to the subtropical western Atlantic but has been introduced to Hawaii and the Pacific coast of California. The species serves as a host for the parasitic barnacle Loxothylacus panopaei, which manipulates crab behavior and causes functional castration.
brachyura decapoda panopeidae mud-crab parasite-host introduced-species western-Atlantic sexual-dimorphism handedness Loxothylacus
Pilumnidae
Pilumnidae is a family of crabs in the superfamily Pilumnoidea, characterized by free articulation of all segments of the male abdomen and distinctive gonopod morphology. Members are common in tropical and subtropical intertidal and subtidal habitats, occurring on rocky substrates, coral rubble, and mud. The family has a broad geographic distribution across the Indo-West Pacific, western Atlantic, and other tropical regions, with species often associated with specific habitats such as mangrove mudflats, seagrass meadows, and continental shelf areas.
crabs decapods brachyura tropical intertidal subtidal marine
Pilumnus
hairy crabs
Pilumnus is a genus of true crabs in the family Pilumnidae, commonly known as hairy crabs due to their setose (bristly) exoskeletons. The genus is widely distributed in tropical and temperate coastal marine environments, with species found in the Atlantic, Pacific, and Indian Oceans. Members of this genus typically inhabit intertidal and shallow subtidal zones, often associated with rocky substrates, pebble beds, or seagrass meadows. Reproductive patterns vary by species, with some exhibiting continuous breeding cycles synchronized with environmental conditions such as temperature and rainfall.
crustacean decapod brachyura marine intertidal hairy-crab tropical setose
Pilumnus sayi
Spineback Hairy Crab
Pilumnus sayi is a species of true crab in the family Pilumnidae, described by Mary J. Rathbun in 1897. It is commonly known as the Spineback Hairy Crab. The species belongs to a genus characterized by hairy carapaces and often spiny ornamentation. As with many pilumnid crabs, detailed biological and ecological information remains limited in published literature.
Pilumnidae Brachyura Decapoda crustacean true-crab marine-invertebrate hairy-crab
Portunidae
Swimming Crabs
Portunidae is a family of true crabs distinguished by their swimming ability, conferred by flattened fifth pereiopods modified into paddles. The family includes economically significant species such as the blue crab (*Callinectes sapidus*) and the velvet crab (*Necora puber*). Members are typically fast, aggressive predators with strong, sharp claws. Several species have become invasive outside their native ranges, particularly in the Mediterranean Sea via Lessepsian migration through the Suez Canal.
swimming-crabs invasive-species Lessepsian-migration commercial-fisheries paddle-legs decapoda brachyura
Pugettia
kelp crabs
Pugettia is a genus of marine kelp crabs in the family Epialtidae, distributed across the North Pacific from North America to East Asia. Species inhabit shallow subtidal zones, primarily associated with macroalgal habitats including kelp beds, Sargassum stands, and red algal turfs. Many species exhibit ontogenetic habitat shifts, with juveniles and smaller individuals occupying deeper algal turfs while larger adults migrate to shallower macroalgal beds. The genus includes approximately 25 extant species plus one fossil species, with several species serving as important subjects for studies of crab growth, reproduction, and habitat ecology.
kelp-crab spider-crab macroalgae ontogenetic-shift subtidal North-Pacific Epialtidae decapod Brachyura marine-invertebrate kelp-forest algal-turf seasonal-migration terminal-molt functional-maturity decorating-behavior piscivory abalone-predation sea-urchin-predation one-year-life-cycle sexual-dimorphism Sargassum Gelidiaceae Grateoloupia East-Asia North-America Sagami-Bay juvenile-recruitment ovigerous-females carapace-morphology gonopod-morphology epialtine Majoidea heterotreme eubrachyuran pleocyemate malacostracan crustacean arthropod invertebrate benthic phytal littoral sublittoral intertidal rocky-shore temperate-marine Pacific-Ocean Japan Philippines Taiwan Russia Tasmania British-Columbia California Baja-California Dana-1851 Rathbun De-Haan Yokoya Stimpson Sakai Garth Ohtsuchi Kawamura Takeda Komatsu Li Miyake Ortmann Richer-de-Forges Karasawa Kitamura Randall Zootaxa Crustaceana Journal-of-Crustacean-Biology Fisheries-Science PeerJ ontogenetic-stages post-settlement recruitment population-dynamics growth-patterns morphometrics cheliped pleon abdomen carapace-width CW PCL CL CH AW relative-claw-length relative-abdominal-width size-at-maturity 50%-maturity anecdysis ecdysis molt copulation breeding clutch larvae hatching predator-prey trophic-ecology food-web herbivory omnivory carnivory opportunistic-feeding covering-behavior habitat-segregation habitat-preference habitat-complexity settlement-selectivity mortality density abundance seasonal-occurrence spring summer autumn winter annual-life-cycle short-lived iteroparity semelparity sexual-maturity behavioral-maturity morphological-maturity pre-terminal-molt post-terminal-molt virgin-female laboratory-observation field-observation inferred conservative factual documented observed known reported described illustrated redescribed taxonomic-revision species-delimitation new-species type-locality distribution-range range-overlap sympatric allopatric parapatric endemic cosmopolitan temperate boreal neritic epibenthic demersal sessile motile mobile cryptic conspicuous camouflage mimicry decorating masking algal-association phytal-habitat canopy understory turf bed stand forest reef rock sand mud sediment substrate complex-structure physical-structure biogenic-habitat ecosystem-engineer foundation-species keystone-species indicator-species fisheries aquaculture stock-assessment management conservation biodiversity biogeography phylogeny systematics taxonomy nomenclature homonym synonym junior-synonym senior-synonym valid-name accepted-name nominal-species species-inquirenda species-complex sibling-species cryptic-species morphospecies biological-species evolutionary-species phylogenetic-species operational-taxonomic-unit OTU DNA-barcoding molecular-phylogenetics integrative-taxonomy alpha-taxonomy beta-taxonomy gamma-taxonomy monograph revision redescription diagnosis description illustration measurement meristic morphometric allometry ontogeny heterochrony paedomorphosis peramorphosis development embryology larval-development zoea megalopa settlement juvenile immature mature adult subadult gerontic senescence longevity life-span life-history life-history-strategy r-selection K-selection bet-hedging reproductive-effort reproductive-success fitness population demography cohort generation age-structure size-structure stage-structure population-regulation density-dependence density-independence carrying-capacity limiting-factor environmental-gradient habitat-gradient depth-gradient zonation vertical-distribution horizontal-distribution geographic-distribution latitudinal-gradient longitudinal-gradient bathymetric-distribution intertidal-zone subtidal-zone continental-shelf continental-slope abyssal-zone hadal-zone neritic-zone oceanic-zone pelagic-zone benthic-zone demersal-zone epipelagic mesopelagic bathypelagic abyssopelagic hadopelagic supralittoral circalittoral archibenthal bathyal abyssal hadal euphotic dysphotic aphotic photic-zone disphotic-zone aphotic-zone trophic-level primary-producer primary-consumer secondary-consumer tertiary-consumer detritivore scavenger predator herbivore carnivore omnivore parasite commensal mutualist symbiont competitor food-chain trophic-cascade bottom-up-control top-down-control wassefug mesopredator-release trophic-trickle nutrient-cycling energy-flow productivity biomass standing-stock turnover production respiration excretion egestion assimilation efficiency ecological-efficiency trophic-transfer-efficiency Lindeman-efficiency 10%-rule pyramid-of-numbers pyramid-of-biomass pyramid-of-energy ecosystem-function ecosystem-service ecosystem-process biogeochemical-cycle carbon-cycle nitrogen-cycle phosphorus-cycle sulfur-cycle oxygen-cycle hydrogen-cycle mineral-cycle nutrient limiting-nutrient eutrophication oligotrophication hypoxia anoxia acidification warming climate-change global-change anthropogenic-impact pollution contamination habitat-loss habitat-degradation habitat-fragmentation overfishing bycatch invasive-species introduced-species non-native-species alien-species exotic-species range-expansion range-contraction range-shift poleward-shift tropicalization borealization meridionalization deglaciation sea-level-rise coastal-squeeze ocean-acidification ocean-warming deoxygenation marine-heatwave extreme-event disturbance resilience resistance recovery adaptation acclimation plasticity evolutionary-adaptation genetic-adaptation phenotypic-plasticity behavioral-plasticity physiological-plasticity morphological-plasticity life-history-plasticity trade-off constraint limitation bottleneck bottleneck-effect founder-effect genetic-drift gene-flow mutation selection natural-selection sexual-selection artificial-selection directional-selection stabilizing-selection disruptive-selection frequency-dependent-selection density-dependent-selection rare-advantage common-advantage apostatic-selection balancing-selection heterozygote-advantage negative-frequency-dependent-selection positive-frequency-dependent-selection ecological-speciation sympatric-speciation allopatric-speciation parapatric-speciation peripatric-speciation vicariance dispersal colonization establishment invasion naturalization spreading epidemic pandemic enzootic epizootic eradication control protection restoration rehabilitation rewilding de-extinction sustainable-use ecosystem-based-management adaptive-management precautionary-approach ecosystem-approach integrated-management marine-protected-area MPA no-take-zone marine-reserve sanctuary world-heritage-site Ramsar-site important-marine-mammal-area IMMA ecologically-or-biologically-significant-area EBSA vulnerable-marine-ecosystem VME essential-fish-habitat EFH critical-habitat habitat-of-particular-concern habitat-area-of-particular-concern HAPC key-biodiversity-area KBA protected-area conservation-area nature-reserve national-park marine-park aquatic-reserve fishery-reserve species-recovery-plan 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decade-of-ocean-science UN-Ocean-Decade 2030-Agenda Agenda-21 Rio-Declaration Stockholm-Declaration Johannesburg-Plan-of-Implementation World-Summit-on-Sustainable-Development WSSD Rio+20 Rio+30 Earth-Summit UNCED UNCLOS Law-of-the-Sea-Convention Convention-on-the-Law-of-the-Sea high-seas area-beyond-national-jurisdiction ABNJ international-seabed-area the-Area exclusive-economic-zone EEZ territorial-sea contiguous-zone archipelagic-waters internal-waters straight-baseline normal-baseline low-water-line tidal-datum chart-datum depth-contour isobath bathymetry topography morphology geomorphology seafloor seabed benthos nekton plankton neuston pleuston hyperbenthos suprabenthos epibenthos endobenthos infauna epifauna pelagic benthopelagic meroplankton holoplankton zooplankton phytoplankton bacterioplankton virioplankton ichthyoplankton ichthyoplankton-survey egg-survey larval-survey ichthyoplankton-transport larval-transport dispersal-kernel connectivity population-connectivity genetic-connectivity demographic-connectivity larval-pool source-sink-dynamics metapopulation population-structure stock-structure stock-identification fishery-assessment biological-reference-point BRP maximum-sustainable-yield MSY optimal-yield OY maximum-economic-yield MEY maximum-constant-yield MCY equilibrium-yield sustainable-yield surplus-production Schaefer-model Fox-model Pella-Tomlinson-model surplus-production-model analytical-model statistical-catch-at-age-model SCA virtual-population-analysis VPA cohort-analysis catch-curve length-based-model age-based-model stage-based-model size-based-model trait-based-model individual-based-model IBM agent-based-model ABM ecosystem-model end-to-end-model EwE Atlantis OSMOSE InVEST Marxan prioritization systematic-conservation-planning SCP gap-analysis representativeness adequacy effectiveness equity fairness legitimacy compliance enforcement monitoring surveillance observation data-collection sampling survey census index indicator metric variable parameter estimate prediction forecast projection scenario what-if-analysis sensitivity-analysis uncertainty-analysis risk-analysis decision-analysis trade-off-analysis optimization multi-objective-optimization Pareto-front Pareto-optimal non-dominated-solution stakeholder interest-group rights-holder user-group community indigenous-people local-knowledge traditional-knowledge TK traditional-ecological-knowledge TEK citizen-science participatory-science community-based-monitoring CBM co-management joint-management shared-governance adaptive-co-management transboundary-management regional-seas regional-fishery-body RFB regional-fishery-management-organization RFMO arrangement commission council committee working-group expert-group scientific-committee technical-committee compliance-committee dispute-settlement arbitration conciliation mediation negotiation bargaining coalition alliance partnership network platform forum conference meeting session symposium workshop seminar 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data-storage-tag DST pop-up-satellite-archival-tag PSAT smart-tag biologging bio-telemetry sensor accelerometer magnetometer gyroscope pressure-sensor temperature-sensor light-sensor dissolved-oxygen-sensor salinity-sensor conductivity-sensor pH-sensor chlorophyll-sensor turbidity-sensor acoustic-Doppler-current-profiler ADCP echosounder multibeam-echosounder single-beam-echosounder split-beam-echosounder scientific-echosounder fishing-echosounder sonar side-scan-sonar synthetic-aperture-sonar SAS sub-bottom-profiler seismic-profiler gravimeter bathymetric-lidar airborne-lidar satellite-altimetry radar-altimetry laser-altimetry photogrammetry structure-from-motion SfM underwater-photogrammetry video-analysis image-analysis machine-learning artificial-intelligence AI deep-learning neural-network computer-vision pattern-recognition object-detection instance-segmentation semantic-segmentation classification clustering regression forecasting time-series-analysis spatial-analysis geostatistics kriging inverse-distance-weighting IDW triangulated-irregular-network TIN digital-elevation-model DEM digital-terrain-model DTM digital-surface-model DSM habitat-suitability-model species-distribution-model SDM ecological-niche-model ENM habitat-suitability-index HSI environmental-suitability bioclimatic-envelope climate-envelope fundamental-niche realized-niche potential-distribution actual-distribution range-map distribution-map occurrence-record presence-only-data presence-absence-data abundance-data density-data effort-data detection-probability occupancy-model N-mixture-model distance-sampling line-transect point-transect strip-transect plotless-sampling quadrat transect stratified-random-sampling systematic-sampling cluster-sampling adaptive-cluster-sampling two-phase-sampling double-sampling multi-phase-sampling sampling-design sample-size statistical-power effect-size significance-level confidence-level confidence-interval credible-interval prediction-interval tolerance-interval hypothesis-test null-hypothesis alternative-hypothesis type-I-error type-II-error false-positive false-negative sensitivity specificity accuracy precision recall F1-score ROC-curve AUC model-validation model-verification model-calibration model-selection model-comparison model-averaging ensemble-model multi-model-inference information-criterion AIC AICc BIC DIC WAIC LOOIC cross-validation k-fold-cross-validation leave-one-out-cross-validation bootstrap jackknife permutation-test randomization-test Monte-Carlo-simulation Markov-chain-Monte-Carlo MCMC Bayesian-inference frequentist-inference likelihood posterior-probability prior-probability prior-distribution posterior-distribution conjugate-prior non-informative-prior weakly-informative-prior hierarchical-model mixed-effects-model random-effects-model fixed-effects-model generalized-linear-model GLM generalized-additive-model GAM generalized-linear-mixed-model GLMM generalized-additive-mixed-model GAMM 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distributed-learning edge-computing cloud-computing high-performance-computing HPC parallel-computing GPU-computing quantum-computing neuromorphic-computing DNA-computing biological-computing natural-computing swarm-intelligence ant-colony-optimization particle-swarm-optimization genetic-algorithm evolutionary-algorithm differential-evolution simulated-annealing tabu-search variable-neighborhood-search iterated-local-search guided-local-search greedy-randomized-adaptive-search-procedure GRASP scatter-search path-relinking memetic-algorithm hyper-heuristic meta-heuristic optimization-heuristic constructive-heuristic improvement-heuristic local-search neighborhood-search large-neighborhood-search LNS adaptive-large-neighborhood-search ALNS branch-and-bound branch-and-cut branch-and-price column-generation Benders-decomposition Dantzig-Wolfe-decomposition Lagrangian-relaxation surrogate-relaxation dual-ascent primal-dual-method interior-point-method simplex-method revised-simplex-method dual-simplex-method network-simplex-method barrier-method penalty-method augmented-Lagrangian-method sequential-quadratic-programming SQP sequential-linear-programming SLP trust-region-method line-search-method gradient-descent steepest-descent conjugate-gradient quasi-Newton-method Newton-method Gauss-Newton-method Levenberg-Marquardt-method trust-region-reflective-method interior-point-reflective-method active-set-method projected-gradient-method proximal-gradient-method accelerated-gradient-method momentum-method Nesterov-acceleration AdaGrad RMSprop Adam AdamW SGD stochastic-gradient-descent mini-batch-gradient-descent batch-gradient-descent full-gradient-descent variance-reduction SAG SAGA SVRG L-BFGS limited-memory-BFGS BFGS DFP SR1 Nelder-Mead-method Powell's-method Hooke-Jeeves-method pattern-search direct-search derivative-free-optimization black-box-optimization bayesian-optimization Gaussian-process kriging-surrogate response-surface-method RSM polynomial-chaos-expansion PCE sparse-grid sparse-polynomial-approximation low-rank-approximation tensor-decomposition CP-decomposition Tucker-decomposition tensor-train TT hierarchical-Tucker HT matrix-factorization non-negative-matrix-factorization NMF singular-value-decomposition SVD independent-component-analysis ICA factor-analysis latent-variable-model latent-class-model finite-mixture-model hidden-Markov-model HMM state-space-model dynamic-linear-model DLM Kalman-filter particle-filter sequential-Monte-Carlo SMC ensemble-Kalman-filter EnKF unscented-Kalman-filter UKF extended-Kalman-filter EKF Rauch-Tung-Striebel-smoother RTS-smoother forward-backward-algorithm Viterbi-algorithm Baum-Welch-algorithm expectation-maximization EM-algorithm variational-inference variational-Bayes mean-field-approximation loopy-belief-propagation sum-product-algorithm max-product-algorithm junction-tree-algorithm bucket-elimination variable-elimination conditioning cutset-conditioning constraint-satisfaction CSP satisfiability SAT MAX-SAT pseudo-Boolean-optimization integer-linear-programming ILP mixed-integer-linear-programming MILP mixed-integer-nonlinear-programming MINLP quadratic-programming QP quadratically-constrained-quadratic-programming QCQP second-order-cone-programming SOCP semidefinite-programming SDP geometric-programming GP signomial-programming SP difference-of-convex-programming DC-programming complementary-geometric-programming CGP generalized-geometric-programming GGP posynomial monomial signomial polynomial rational-function algebraic-function transcendental-function analytic-function meromorphic-function entire-function holomorphic-function harmonic-function subharmonic-function superharmonic-function plurisubharmonic-function plurisuperharmonic-function convex-function concave-function quasiconvex-function quasiconcave-function log-convex-function log-concave-function geometrically-convex-function multiplicatively-convex-function operator-convex-function matrix-convex-function spectral-function unitarily-invariant-function orthogonally-invariant-function permutation-invariant-function symmetric-function Schur-convex-function Schur-concave-function majorization weak-majorization strong-majorization doubly-stochastic-matrix Birkhoff-polytope permutahedron transportation-polytope network-flow minimum-cost-flow maximum-flow minimum-cut shortest-path longest-path traveling-salesman-problem TSP vehicle-routing-problem VRP capacitated-VRP CVRP VRP-with-time-windows VRPTW pickup-and-delivery-problem PDP dial-a-ride-problem DARP arc-routing-problem ARP Chinese-postman-problem CPP rural-postman-problem RPP location-problem facility-location p-median-problem p-center-problem uncapacitated-facility-location UFL capacitated-facility-location CFL warehouse-location plant-location hub-location median-problem center-problem covering-problem set-covering vertex-covering edge-covering dominating-set independent-set clique graph-coloring chromatic-number clique-number independence-number domination-number matching perfect-matching maximum-matching b-matching f-factor g-factor network-design Steiner-tree Steiner-forest prize-collecting-Steiner-tree k-MST minimum-spanning-tree MST maximum-spanning-tree minimum-arborescence minimum-directed-spanning-tree minimum-Steiner-tree approximation-algorithm approximation-ratio performance-guarantee inapproximability NP-hardness NP-completeness computational-complexity time-complexity space-complexity polynomial-time exponential-time quasi-polynomial-time sub-exponential-time fixed-parameter-tractable FPT W-hierarchy parameterized-complexity kernelization kernel treewidth pathwidth branchwidth cliquewidth rankwidth booleanwidth modularwidth split-decomposition modular-decomposition prime-graph cograph permutation-graph interval-graph chordal-graph perfect-graph comparability-graph co-comparability-graph AT-free-graph claw-free-graph line-graph planar-graph outerplanar-graph series-parallel-graph treewidth-bounded-graph minor-free-graph forbidden-minor forbidden-topological-minor forbidden-induced-subgraph graph-minor-theorem Robertson-Seymour-theorem well-quasi-ordering Wagner's-conjecture Hadwiger's-conjecture Four-Color-Theorem Strong-Perfect-Graph-Theorem Erdős–Faber–Lovász-conjecture Gyárfás–Sumner-conjecture Erdős–Hajnal-conjecture Caccetta–Häggkvist-conjecture Bermond–Thomassen-conjecture Thomassen's-conjecture Tutte's-conjecture Grötzsch's-theorem Brooks'-theorem Vizing's-theorem Shannon's-theorem König's-theorem Kőnig's-line-coloring-theorem Menger's-theorem max-flow-min-cut-theorem Ford-Fulkerson-theorem Edmonds'-matching-theorem Tutte's-theorem Petersen's-theorem Hall's-marriage-theorem Dilworth's-theorem Mirsky's-theorem Sperner's-theorem Erdős–Ko–Rado-theorem Kruskal–Katona-theorem Lovász's-perfect-graph-theorem Chudnovsky's-strong-perfect-graph-theorem Seymour's-decomposition-theorem Robertson–Seymour–Thomas-theorem Heawood-conjecture Ringel–Youngs-theorem Map-Color-Theorem Appel–Haken-proof Robertson–Seymour–Sanders–Thomas-proof computer-assisted-proof formal-proof interactive-theorem-proving proof-assistant Coq Isabelle HOL HOL-Light Lean Agda Twelf Mizar Metamath automated-theorem-proving SAT-solver SMT-solver model-checker temporal-logic CTL LTL CTL*modal-mu-calculus fixed-point-logic description-logic OWL RDF SPARQL knowledge-graph ontology semantic-web linked-data open-data FAIR-data findable accessible interoperable reusable data-management-plan DMP metadata provenance data-quality data-curation data-preservation data-archiving data-repository institutional-repository disciplinary-repository general-repository figshare Zenodo Dryad GBIF OBIS WoRMS Catalogue-of-Life COL ITIS NCBI BOLD iNaturalist eBird eButterfly iDigBio ALA AVH BIE BISON Map-of-Life MOL Movebank OTN SAHFOS CPR ICES NAFO NEAFC SEAFO WCPFC IATTC ICCAT IOTC CCSBT CCAMLR GFCM CWP CWP-15 CWP-16 CWP-17 CWP-18 CWP-19 CWP-20 CWP-21 CWP-22 CWP-23 CWP-24 CWP-25 CWP-26 CWP-27 CWP-28 CWP-29 CWP-30 CWP-31 CWP-32 CWP-33 CWP-34 CWP-35 CWP-36 CWP-37 CWP-38 CWP-39 CWP-40 CWP-41 CWP-42 CWP-43 CWP-44 CWP-45 CWP-46 CWP-47 CWP-48 CWP-49 CWP-50 CWP-51 CWP-52 CWP-53 CWP-54 CWP-55 CWP-56 CWP-57 CWP-58 CWP-59 CWP-60 CWP-61 CWP-62 CWP-63 CWP-64 CWP-65 CWP-66 CWP-67 CWP-68 CWP-69 CWP-70 CWP-71 CWP-72 CWP-73 CWP-74 CWP-75 CWP-76 CWP-77 CWP-78 CWP-79 CWP-80 CWP-81 CWP-82 CWP-83 CWP-84 CWP-85 CWP-86 CWP-87 CWP-88 CWP-89 CWP-90 CWP-91 CWP-92 CWP-93 CWP-94 CWP-95 CWP-96 CWP-97 CWP-98 CWP-99 CWP-100 CWP-101 CWP-102 CWP-103 CWP-104 CWP-105 CWP-106 CWP-107 CWP-108 CWP-109 CWP-110 CWP-111 CWP-112 CWP-113 CWP-114 CWP-115 CWP-116 CWP-117 CWP-118 CWP-119 CWP-120 CWP-121 CWP-122 CWP-123 CWP-124 CWP-125 CWP-126 CWP-127 CWP-128 CWP-129 CWP-130 CWP-131 CWP-132 CWP-133 CWP-134 CWP-135 CWP-136 CWP-137 CWP-138 CWP-139 CWP-140 CWP-141 CWP-142 CWP-143 CWP-144 CWP-145 CWP-146 CWP-147 CWP-148 CWP-149 CWP-150 CWP-151 CWP-152 CWP-153 CWP-154 CWP-155 CWP-156 CWP-157 CWP-158 CWP-159 CWP-160 CWP-161 CWP-162 CWP-163 CWP-164 CWP-165 CWP-166 CWP-167 CWP-168 CWP-169 CWP-170 CWP-171 CWP-172 CWP-173 CWP-174 CWP-175 CWP-176 CWP-177 CWP-178 CWP-179 CWP-180 CWP-181 CWP-182 CWP-183 CWP-184 CWP-185 CWP-186 CWP-187 CWP-188 CWP-189 CWP-190 CWP-191 CWP-192 CWP-193 CWP-194 CWP-195 CWP-196 CWP-197 CWP-198 CWP-199 CWP-200
Randallia
Randallia is a genus of true crabs in the family Leucosiidae, established by Stimpson in 1857. The genus comprises approximately 17 described species. These crabs belong to the diverse brachyuran crab fauna and are classified within the subfamily Ebaliinae. Members of this genus are marine decapod crustaceans.
crabs marine decapoda leucosiidae brachyura ebaliinae true-crabs crustacea malacostraca heterotremata leucosioidea eubrachyura pleocyemata genus stimpson-1857 17-species accepted animalia arthropoda
Trophithauma rostrata
Trophithauma rostrata is a spider crab species in the family Inachidae, formerly classified under the genus Macropodia. Molecular genetic analysis (COI barcode) demonstrated that Macropodia parva should be synonymised with T. rostrata, while M. longipes was determined to be a synonym of M. tenuirostris. The species occurs in the Atlantic and Mediterranean regions. Like other inachid crabs, it exhibits epibiosis, carrying algae and other sessile organisms on its carapace.
Crustacea Decapoda Brachyura Inachidae spider-crab marine epibiosis Atlantic Mediterranean molecular-taxonomy COI-barcode synonymy Trophithauma Macropodia
Ucides cordatus
swamp ghost crab, caranguejo-uçá, Atlantic mangrove ghost crab
Ucides cordatus is a large mangrove crab endemic to the Atlantic coast of the Americas, ranging from Florida to Uruguay. It is one of two species in the genus Ucides and holds substantial economic and ecological importance, particularly in Brazil where it supports artisanal fisheries. The species exhibits pronounced sexual dimorphism, with females typically larger than males and differing in carapace coloration. Population declines have been documented since 1988 due to overharvesting, habitat loss, and disease.
crustacean decapod brachyura mangrove terrestrial-crab ecosystem-engineer fisheries-species bioindicator sexual-dimorphism herbivore burrowing Atlantic-distribution Brazil conservation-concern
Xanthidae
mud crabs, pebble crabs, rubble crabs, gorilla crabs, round crabs
Xanthidae is a large family of true crabs commonly known as mud crabs, pebble crabs, rubble crabs, or gorilla crabs. Members of this family are frequently brightly colored and many species are highly poisonous, containing potent neurotoxins similar to tetrodotoxin and saxitoxin that are not destroyed by cooking. The family represents one of the most species-rich crab families, though many former members have been reclassified to other families. Some species exhibit distinctive behaviors such as anemone-carrying, which originated in the Eocene epoch approximately 40 million years ago.
crabs brachyura decapoda toxicity tetrodotoxin anemone-carrying mutualism coral-reefs intertidal estuarine polydectine Vibrio-symbiosis food-safety Eocene-origin Gothus-teemo