Free living animals; body totally covered in a bivalved carapace, though appendages are visible
Step 2
Sessile animals; body at least partly covered with calcareous plates
Step 48
Free living animals; with or without a carapace, but exposing parts of a segmented body (sometimes only at the underside)
Step 70
505 possible taxa remaining show common names
- Abludomelita obtusata
- Acanthocythereis dunelmensis
- Acidostoma nodiferum
- Acidostoma obesum
- Aega monophthalma
- Aega psora
- Aega rosacea
- Aega ventrosa
- Allomelita pellucida
- Alpheus glaber
- Ampelisca
- Ampelisca aequicornis
- Ampelisca brevicornis
- Ampelisca gibba
- Ampelisca macrocephala
- Ampelisca spinipes
- Ampelisca tenuicornis
- Ampelisca typica
- Amphilochoides boecki
- Amphilochoides serratipes
- Amphilochus manudens
- Amphilochus spencebatei
- Amphilochus tenuimanus
- Ampithoe gammaroides
- Ampithoe rubricata
- Anapagurus chiroacanthus
- Anapagurus hyndmanni
- Anchialina agilis
- Anilocra frontalis
- Aoridae
- Apherusa cirrus
- Apherusa clevei
- Apherusa jurinei
- Apherusa ovalipes
- Apseudes latreillii
- Apseudes talpa
- Arcturella dilatata
- Argissa hamatipes
- Armadillidium album
- Arrhis phyllonyx
- Asellus aquaticus
- Atelecyclus rotundatus
- Athanas nitescens
- Atylus falcatus
- Atylus guttatus
- Atylus swammerdami
- Atylus vedlomensis
- Balanus amphitrite
- Balanus balanus
- Balanus crenatus
- Balanus hameri
- Balanus improvisus
- Bathynectes longipes
- Bathynectes maravigna
- Bathyporeia guilliamsoniana
- Bathyporeia nana
- Bathyporeia pilosa
- Bathyporeia tenuipes
- Bodotria arenosa
- Bodotria pulchella
- Bodotria scorpioides
- Bopyrina giardi
- Bopyrus fougerouxi
- Brachydiastylis resima
- Byblis gaimardi
- Bythocythere robinsoni
- Bythocythere zetlandica
- Calathura brachiata
- Callianassa tyrrhena
- Callinectes sapidus
- Calliopius laeviusculus
- Calocaris macandreae
- Campylaspis costata
- Campylaspis glabra
- Campylaspis rubicunda
- Campylaspis sulcata
- Cancer bellianus
- Cancer pagurus
- Caprella acanthifera
- Caprella equilibra
- Caprella linearis
- Caprella macho
- Caprella septentrionalis
- Caprella tuberculata
- Carcinus maenas
- Caridion gordoni
- Caridion steveni
- Carinocythereis whitei
- Celtia quadridentata
- Cerapus crassicornis
- Cheirocratus
- Cheirocratus assimilis
- Cheirocratus sundevallii
- Chelura terebrans
- Chthamalus stellatus
- Conchoderma auritum
- Conchoderma virgatum
- Copepoda
- Coronula diadema
- Coronula reginae
- Corophium acherusicum
- Corophium affine
- Corophium arenarium
- Corophium bonnellii
- Corophium crassicorne
- Corophium curvispinum
- Corophium insidiosum
- Corophium lacustre
- Corophium multisetosum
- Corophium sextonae
- Corophium volutator
- Corystes cassivelaunus
- Crangon allmani
- Crangon crangon
- Cressa dubia
- Cressa minuta
- Cumella pygmaea
- Cumopsis goodsiri
- Cyamus catodontis
- Cyathura carinata
- Cyprideis torosa
- Cythere lutea
- Cytheropteron latissimum
- Dendrotion spinosum
- Desmosoma tenuimanu
- Dexamine thea
- Diastylis bradyi
- Diastylis cornuta
- Diastylis laevis
- Diastylis lucifera
- Diastylis rathkei
- Diastylis rugosa
- Diastylis tumida
- Diastyloides biplicata
- Dichelopandalus bonnieri
- Dikerogammarus villosus
- Diogenes pugilator
- Dorhynchus thomsoni
- Dromia personata
- Dynamene bidentata
- Dyopedos monacanthus
- Dyopedos porrectus
- Ebalia tuberosa
- Ebalia tumefacta
- Echinogammarus pirloti
- Echinogammarus planicrurus
- Echinogammarus stoerensis
- Elasmopus rapax
- Elminius modestus
- Elofsonella concinna
- Entionella monensis
- Epimeria cornigera
- Epimeria parasitica
- Ericthonius
- Ericthonius difformis
- Ericthonius punctatus
- Ericthonius rubricornis
- Eriocheir sinensis
- Eriopisa elongata
- Erythrops elegans
- Erythrops erythrophthalma
- Eualus gaimardii
- Eualus occultus
- Eualus pusiolus
- Eucythere argus
- Eudorella emarginata
- Eudorella truncatula
- Eudorellopsis deformis
- Euonyx chelatus
- Eurycope mutica
- Eurydice affinis
- Eurydice grimaldii
- Eurydice pulchra
- Eurydice spinigera
- Eurydice truncata
- Eurynome aspera
- Eurynome spinosa
- Galathea dispersa
- Galathea intermedia
- Galathea squamifera
- Galathea strigosa
- Gammarella fucicola
- Gammarellus angulosus
- Gammarellus homari
- Gammaropsis maculata
- Gammaropsis nitida
- Gammaropsis palmata
- Gammarus crinicornis
- Gammarus duebeni
- Gammarus finmarchicus
- Gammarus insensibilis
- Gammarus locusta
- Gammarus marinus
- Gammarus obtusatus
- Gammarus oceanicus
- Gammarus salinus
- Gammarus tigrinus
- Gammarus zaddachi
- Gastrosaccus lobatus
- Gastrosaccus normani
- Gastrosaccus sanctus
- Gastrosaccus spinifer
- Geryon tridens
- Gitana sarsi
- Gitanopsis bispinosa
- Gnathia maxillaris
- Gnathia oxyuraea
- Gnathia vorax
- Goneplax rhomboides
- Guernea coalita
- Gyge branchialis
- Haploops setosa
- Haploops tubicola
- Hardametopa nasuta
- Harpinia antennaria
- Harpinia crenulata
- Harpinia mucronata
- Haustorius arenarius
- Hemigrapsus penicillatus
- Hemilamprops rosea
- Hemimysis lamornae
- Heterocythereis albomaculata
- Heteromysis formosa
- Heterotanais oerstedi
- Hippolyte varians
- Hippomedon denticulatus
- Homarus gammarus
- Hyale pontica
- Hyale prevosti
- Hyale stebbingi
- Hyas araneus
- Hyas coarctatus
- Hyperia galba
- Ichnopus spinicornis
- Idotea baltica
- Idotea chelipes
- Idotea granulosa
- Idotea metallica
- Inachus dorsettensis
- Inachus leptochirus
- Inachus phalangium
- Ione thoracica
- Iphimedia obesa
- Iphimedia spatula
- Iphinoe serrata
- Iphinoe trispinosa
- Isaea elmhirsti
- Ischnosoma bispinosum
- Ischyrocerus anguipes
- Isocyamus delphinii
- Jaera albifrons
- Jaera ischiosetosa
- Jaera praehirsuta
- Jaera syei
- Janira maculosa
- Janiropsis breviremis
- Jassa falcata
- Jassa herdmani
- Jassa marmorata
- Jassa ocia
- Jonesia acuminata
- Krithe praetexta
- Lafystius sturionis
- Lamprops fasciata
- Lebbeus polaris
- Lekanesphaera hookeri
- Lekanesphaera rugicauda
- Lembos websteri
- Lepas anatifera
- Lepas anserifera
- Lepas fascicularis
- Lepas hilli
- Lepas pectinata
- Leptaspidea brevipes
- Leptocheirus hirsutimanus
- Leptocheirus pectinatus
- Leptocheirus pilosus
- Leptochelia savignyi
- Leptocythere castanea
- Leptognathia brevimana
- Leptognathia filiformis
- Leptomysis gracilis
- Leptomysis lingvura
- Leptostylis ampullacea
- Leptostylis villosa
- Leucon nasica
- Leucothoe incisa
- Leucothoe spinicarpa
- Ligia oceanica
- Liljeborgia kinahani
- Limnoria lignorum
- Limnoria quadripunctata
- Liocarcinus arcuatus
- Liocarcinus corrugatus
- Liocarcinus depurator
- Liocarcinus holsatus
- Liocarcinus marmoreus
- Liocarcinus pusillus
- Liocarcinus vernalis
- Lithodes maja
- Lophogaster typicus
- Lysianassa ceratina
- Lysianassa plumosa
- Macrocypris minna
- Macropipus tuberculatus
- Macropodia deflexa
- Macropodia linaresi
- Macropodia parva
- Macropodia rostrata
- Macropodia tenuirostris
- Macrostylis spinifera
- Maera loveni
- Maera othonis
- Maerella tenuimana
- Maja squinado
- Megamphopus cornutus
- Meganyctiphanes norvegica
- Meiosquilla desmaresti
- Melita dentata
- Melphidippella macra
- Menigrates obtusifrons
- Menigratopsis svennilssoni
- Mesopodopsis slabberi
- Metopa alderi
- Metopa bruzelii
- Metopa latimana
- Metopa propinqua
- Metopa robusta
- Microdeutopus anomalus
- Microdeutopus gryllotalpa
- Microdeutopus versiculatus
- Microprotopus maculatus
- Monoculodes packardi
- Monoculodes subnudus
- Munna kroyeri
- Munna limicola
- Mysidopsis angusta
- Mysidopsis didelphys
- Mysidopsis gibbosa
- Nannastacus unguiculatus
- Nannonyx goesi
- Nebalia bipes
- Necora puber
- Neomysis integer
- Normanion quadrimanus
- Nyctiphanes couchi
- Odius carinatus
- Opisa eschrichtii
- Orchestia aestuarensis
- Orchestia cavimana
- Orchestia gammarellus
- Orchestia mediterranea
- Orchestia roffoensis
- Orchomene humilis
- Orchomene nanus
- Orchomene pinguis
- Ostracoda
- Pachygrapsus transversus
- Pagurus bernhardus
- Pagurus cuanensis
- Pagurus prideaux
- Pagurus pubescens
- Pagurus variabilis
- Palaemon adspersus
- Palaemon longirostris
- Palaemon serratus
- Pandalina brevirostris
- Pandalus borealis
- Pandalus montagui
- Pandalus propinquus
- Paracypris polita
- Paradoxostoma angliorum
- Paradoxostoma ensiforme
- Paradoxostoma hibernicum
- Paradoxostoma sarniense
- Paradoxostoma tenuissimum
- Paradoxostoma variabile
- Paragnathia formica
- Parametaphoxus fultoni
- Paramphilochoides intermedius
- Paramphilochoides odontonyx
- Paramunna bilobata
- Paraphoxus oculatus
- Parapleustes bicuspis
- Paromola cuvieri
- Perioculodes longimanus
- Perrierella audouiniana
- Petalosarsia declivis
- Photis reinhardi
- Phoxocephalus
- Phoxocephalus holbolli
- Phtisica marina
- Pilumnus hirtellus
- Pinnotheres pinnotheres
- Pinnotheres pisum
- Pinnotherion vermiforme
- Pirimela denticulata
- Pisa tetraodon
- Planes minutus
- Platorchestia platensis
- Platycyamus thompsoni
- Pleurocrypta longibranchiata
- Pleurocrypta marginata
- Pleurocrypta porcellanae
- Pleurogonium inerme
- Pleurogonium rubicundum
- Pleurogonium spinosissimum
- Podocerus variegatus
- Polybius henslowii
- Pontocrates altamarinus
- Pontocypris mytiloides
- Pontophilus bispinosus
- Pontophilus echinulatus
- Pontophilus fasciatus
- Pontophilus norvegicus
- Pontophilus sculptus
- Pontophilus spinosus
- Pontophilus trispinosus
- Porcellana platycheles
- Portumnus latipes
- Portunion maenadis
- Praunus flexuosus
- Praunus neglectus
- Proboloides calcarata
- Processa canaliculata
- Processa edulis
- Processa modica
- Processa nouveli
- Prodajus ostendensis
- Propontocypris pirifera
- Propontocypris trigonella
- Pseudione proxima
- Pseudoarachne hirsuta
- Pseudocuma gilsoni
- Pseudocuma longicornis
- Pseudocuma similis
- Pseudocythere caudata
- Pseudoparatanais batei
- Pseudoprotella phasma
- Pseudorchestoidea brito
- Pseudotanais forcipatus
- Pterygocythereis jonesii
- Rhithropanopeus harrisii
- Rocinela danmoniensis
- Saduria entomon
- Sarsicytheridea bradii
- Sarsicytheridea punctillata
- Scalpellum scalpellum
- Scalpellum stroemi
- Schistomysis kervillei
- Schistomysis ornata
- Schistomysis parkeri
- Schistomysis spiritus
- Sclerochilus contortus
- Sclerochilus rudjakovi
- Sclerochilus schornikovi
- Scopelocheirus hopei
- Scutocyamus parvus
- Semibalanus balanoides
- Siphonoecetes kroyeranus
- Siriella armata
- Siriella clausii
- Siriella jaltensis
- Socarnes erythtophthalmus
- Socarnes filicornis
- Sphaeroma monodi
- Sphaeroma serratum
- Spirontocaris lilljeborgi
- Spirontocaris spinus
- Stegocephaloides christianiensis
- Stenopleustes nodifer
- Stenothoe microps
- Stenothoe monoculoides
- Stenula rubrovittata
- Stylocheiron longicorne
- Sunamphitoe pelagica
- Synchelidium haplocheles
- Synchelidium maculatum
- Synchelidium tenuimanum
- Talitrus saltator
- Talorchestia deshayesii
- Tanais dulongii
- Tanaopsis graciloides
- Thia scutellata
- Thoralus cranchii
- Thysanoessa inermis
- Thysanoessa longicaudata
- Tiron spiniferus
- Tmetonyx cicada
- Tryphosella horingi
- Tryphosella nanoides
- Typhlotanais aequiremis
- Unciola crenatipalma
- Unciola planipes
- Upogebia deltaura
- Upogebia pusilla
- Upogebia stellata
- Urothoe poseidonis
- Vaunthompsonia cristata
- Verruca stroemia
- Westwoodilla caecula
- Xaiva biguttata
- Xantho pilipes
- Xenobalanus globicipites
- Xestoleberis depressa
Decision path