DIVERSITY OF LIFE

HIERARCHICAL CLASSIFICATION OF THE SPIRALIA (GIRIBET 2002)

EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>METAZOA>BILATERIA>PROTOSTOMATA>SPIRALIA

The taxonomic system below is modified from Brusca and Brusca (2003), Valentine (2004), and Nielsen (2001).  However, there have been major changes in the relative positions of the phyla due to more recent molecular phylogenetic work (summarized in Edgecombe et al. 2011).  Please see the respective phylum pages for descriptions of the higher taxa.  

FIGURE 1.  Reduced cladogram of the Spiralia, detail from Figure 1, Description of the Spiralia.  The topology of the cladogram is from Edgecombe et al. (2011) and Helmkampf et al. (2008).  Click on the clades below to navigate in the hierarchical system below.

Pl = Platyzoa

Gn = Gnathifera

T  = Trochozoa.

Po = Polyzoa

Bz = Brachiozoa

Eu = Eutrochozoa

Click on the terminal taxa in the cladogram to go to the respective classification to the class-level.

 
   
TROCHOZOA (Roule 1891)  

EUTROCHOZOA (Eernisse et al. 1992)

 

PHYLUM ANNELIDA (Lamarck 1809)

CLASS POLYCHAETA Grube 1850 (25 ORDERS)

Abarenicola, Arenicola, Capitella, Notomastus, Clymenella, Maldane, Praxiella.

Chaetopterus, Mesochaetopterus, Phylochaetopteris

Cirratulus, Cirriformia, Dodecaceria.

Arabella, Drilonereis, Eunice, Marphysa, Palola, Ichthyotomus, Lumbrinerides, Ninoe, Diopatra, Onuphis, Paradiopatra.

Asteriomyzostomum, Cystimyzostomum, Myzostoma.

Armandia, Euzonus, Ophelia, Polyphthalmus.

Polyphysia.

Polydora, Scolelepis, Spio, Spiophanes.

Orbinia, Scoloplos.

Owenia.

Alciopa, Alciopina, Torrea, Vanadis, Aphrodita, Pontogenia, Glycera, Glycerella, Hemipodus, Aglaphamus, Micronephtyes, Nephtyes, Cheilonereis, Dendronereis, Neanthes, Nereis, Platynereis, Eteone, Eulalia, Notophyllum, Phyllodoce, Arctonoe, Gorgoniapolynoe, Eulagisca, Halosydna, Harmothoe, Hesperonoe, Polynoa, Autolytus, Brania, Odontosyllis, Trypanosyllis, Tomopteris.

Bispira, Eudistylia, Fabricia, Myxicola, Sabella, Schizobranchia, Filograna, Hydroides, Serpula, Spirobranchus, Circeis, Paralaeospira, Spirorbis.

Amphictene, Pectinaria, Petta, Phragmatopoma, Sabellaria, Amphitrite, Pista, Polycirrus, Terrebella, Thelepus,

Manayunkia, Polygordius. 

CLASS POGONOPHORA

SUBCLASS PERVIATA (1 ORDER)

Birstenia, Heptabrachia, Diplobrachia, Lamellissbella, Oligobrachia, Polybrachia, Siboglinum, Spirobrachia, Zenkevitchiana.

SUBCLASS OBDURATA (ALSO CALLED VESTMENTIFERA; 1 ORDER)

Escarpia, Lamellabrachia, Oasisia, Ridgeia, Riftia, Tevnia.

CLASS ECHIURIDA (3 ORDERS)

Achaetobonellia, Bonellia, Bruunella, Echiurus, Listriolobus, Thalassema, Tatjanellia

Urechis.

Ikeda.

CLASS CLITELLATA (7 ORDERS IN 2 SUBCLASSES)

Subclass Oligochaeta (4 ORDERS) 

Aeolosoma.

Lamprodillus, Rhynchelmis, Stylodrilus, Styloscolex, Trichodrylus, Desmogaster, Moniligaster.

Alma, Callidrilus, Megascolides, Megascolex, Pheretima, Inanidrillus, Olavius, Branchiura, Clitellio, Limnodrilus, Tubifex, Branchiodrilus, Dero, Ripistes, Slavina, Stylaria, Allolobophora, Diporodrilus, Eisenia,  Lumbricus

Nais, Enchytraeus,  Allolobophora.

Subclass Hirudinoidea (3 ORDERS)

Acanthobdella.

Branchiobdella, Cambarinicola, Stephanodrilus.

Erpobdella, Glossophonia, Haemapsida, Hirudo, Oxobranchus, Piscicola, Pontobdella, Placobdella, , Macrobdella, Haemopis, Dina.

CLASS SIPUNCULA (2 ORDERS, EACH IN A SEPARATE SUBCLASS)

SUBCLASS SIPUNCULIDA (1 ORDER)

Themiste, Onchnesoma, Phascolion, Golfingia, Nephasoma, Thysanocardia.

Phascolopsis, Siphonomecus, Siphonosoma, Sipunculus, Xenosiphon.

SUBCLASS PHASCOLOSOMIDA (1 ORDER)

Aspidosiphon, Cloeosiphon, Lithacrosiphon.

Antillesoma, Apionsoma, Phascolosoma, Dendrostomum.

 

PHYLUM MOLLUSCA (Linnaeus 1758)

CLASS APLACOPHORA (2 SUBCLASSES, EACH WITH A SINGLE ORDER)

Subclass Chaetodermomorpha

Chaetoderma, Falcidens, Limifossor, Psilodens, Scutopus.

Subclass Neomeniomorpha

Chevroderma, Dondersia, Epimenia, Kruppomenia, Neomenia, Proneomenia, Pruvotina, Rhopalomenia, Spengalomenia.

CLASS MONOPLACOPHORA (1 ORDER)

Laevipilina, Micropilina, Monoplacophorus, Neopilina, Rokopella, Vema.

CLASS POLYPLACOPHORA (3 ORDERS)

Chloriplax, Lepidochiton, Lepidopleurus, Oldroydia.

Callistochiton, Chaetopleura, Ischnochiton, Katharina, Lepidozona, Mopalia, Placiphorella, Schizoplax, Tonicella.

Acanthochitona, Chitona, Cryptochiton, Cryptoplax.

CLASS GASTROPODA (15 ORDERS IN 3 SUBCLASSES)

Subclass Prosobranchia 

Perotrochus, Pleurotomaria, Scissurella, Haliotis, Diodora, Fissurella, Lucapinella, Puncturella, Acamea, Collistella, Lottia, Calliostoma, Margatites, Patella, Tegula, Trochus, Astrea, Nerita, Theodoxus, Alcidia, Helicinia, Crepidula.

Hydrobia, Viviparus, Littorina, Turitella, Caecum, Serpulorbis, Tripsycha, Vermetus, Vermicularia, Cerithium, Liocerithium, Cerithidea, Strombus, Epitonium, Janthina, Hipponix, Capulus, Calyptraea, Crepidula, Crucibulum, Carinaria, Natica, Polinices, Erato, Trivia, Cypraea, Jenneria, Ovula, Simnia, Malea, Cassis, Ficus.

Buccinum, Cantharus, Macron, Metula, Anachis, Columbella, Mitrella, Nassarina, Pyrene, Strombina, Coralliophila, Latiaxis, Fasciolaria, Fusinus, Leucozonia, Troschellia, Harpa, Garnula, Melongena, Mitra, Subcancilla, Cerastoma, Hexaplex, Murex, Phyllonotus, Pteropurpura, Pterynotus, Acanthina, Morula, Neorapana, Nucella, Purpura, Thais, Nassarius, Cymbium, Lyria, Voluta, Admete, Cancellaria, Conus, Crassispira,Terebra.

Subclass Opisthobranchia: 

Acochlidium, Unela.

Acteon, Aglaja, Bulla, Chelidonura, Haminoea, Navanax, Retusa, Rictaxis, Scaphander.

Ilbia, Runcina

Berethellina, Elysia, Oxynoe, Tridachia.

Aplysia, Dolabella, Stylocheilus.

Clio, Limacina.

Clione.

Berthellina, Gymnotoplax, Pleurobranchus, Tylodina.

Acanthodoris, Aegires, Aeolidia, Aeolis, Armina, Cavolina, Chromodoris, Corambe, Coryphella, Dendrodoris, Dendronotus, Diaulula, Doris, Embletonia, Fiona, Glaucus, Hermisenda, Hexabranchus, Hopkinsia, Limacina, Janolus, Phidiana, Philine, Phyllidia, Platydoris, Pneumoderma, Polycera, Rostanga, Scyllaea, Tambja, Trinschesia

Subclass Pulmonata: 

Cassidula, Ellobium, Otina.

Bulinus, Carychium, Chilina, Lanx, Physa, Planorbis, Polygyra, Siphonaria, Trimusculus.

Achatina, Arion, Bulimulus, Cepaea, Haplotrema, Helix, Liguus, Limax, Megaspira, Oreohelix, Pupilla, Rachis, Succinea, Vertigo.

Onchidella, Onchidium, Rhodope.

CLASS BIVALVIA (ALSO CALLED PELECYPODA OR LAMELLIBRANCHIATA; 10 ORDERS IN 3 SUBCLASSES)

Subclass PALAEOTAXODONTA:

Malletia, Nucula, Yoldia.

SUBCLASS CRYPTODONTA

Solemya.

Subclass PTERIODONTA:

Adula, Brachydontes, Lithophaga, Modiolus, Mytilus, Anadara, Arca, Barbatia, Glycymeris, Crassostrea, Ostrea, Pinctada, Pteria, Malleus, Atrina, Pinna, Lima, Chlamys, Lyropecten, Pecten, Spondylus, Anomia, Pododesmus.

SUBCLASS PALAEOHETERODONTA

Lampsilis, Anodonta, Ensis, Quadrula.

SUBCLASS HETERODONTA

Clinocardium, Laevicardium, Trachycardium, Cardita, Tridacna, Mactra, Ensis, Solen, Florimetis, Macoma, Tellina, Leptomya, Semele, Donax, Chione, Dosinia, Pitar, Protothaca, Tivela, Corbicula, Cardium, Mercenaria, Unio, 

Barnea, Chaceia, Martesia, Pholas, Bankia, Toredo, Corbula, Mya.

Subclass Anomalodesmata: 

Cuspidaria, Poromya, Pandora.

CLASS SCAPHOPODA (2 ORDERS)

Dentalium, Fustiaria, Laevidentalium, Pulsellum, Annulipulsellum, Cadulus, Gadila.

CLASS CEPHALOPODA (5 ORDERS IN 2 SUBCLASSES)

Subclass Nautiloidea (also called Tetrabranchiata): 

Nautilus.

Subclass Coleoidea (also called Dibranchiata): 

Rossia, Sepia, Spirula.

Architeuthis, Bathyteuthis, Chiroteuthis, Doryteuthis, Dosidiscus, Gonatus, Histioteuthis, Illex, Loligo, Lycoteuthis, Octopoteuthis, Ommastraphes.

Argonauta, Octopus, Opisthoteuchis, Stauroteuthis.

Vampyroteuthis.

 

PHYLUM NEMERTEA (Schultze 1851)

CLASS ANOPLA (2 ORDERS)

Carinoma, Hubrechtella, Tubulanus, Cepahalothrix, Baseodiscus, Lineus, Cerebratulus, Micrura, Paralineus.

CLASS ENOPLA (2 ORDERS)

Annulonemertes, Carcinonemertes, Emplectonema, Geonemertes, Paranemertes, Prostoma, Amphiporus, Hubrechtonemertes, Nectonemertes, Pelagonemertes,  Malacobdella.

 

PHYLUM RHOMBOZOA (van Beneden 1876)

CLASS RHOMBOZOIDA (2 ORDERS)

Conocyema, Dicyema, Dicyemennea, Microcyema, Pseudicyema.

 

PHYLUM ORTHONECTOZOA (Giard 1877)

CLASS ORTHONECTIDA (1 ORDER).

Ciliocincta, Rhopalura, Stoecharthrum.

 

BRACHIOZOA (Helmkampf et al. 2008)

 
PHYLUM BRACHIOPODA (Dumeril 1806)

CLASS INARTICULATA (2 ORDERS)

Crania, Discinisca, Glottidia, Lingula, Pelagodiscus.

CLASS ARTICULATATA (3 ORDERS)

Argyrotheca, Chilidonophora, Dallina, Gryphus, Hemithyris, Lacazella, Laqueus, Liothyrella, Magellania, Orthis, Terebratula, Terebratulina, Terrebratella, Thecidellina, Trichosina.

 
PHYLUM PHORONIDA (Hatschek 1888)

CLASS PHORONATA

Phoronis, Phoronopsis

 
POLYZOA (Thompson 1830)
 
PHYLUM ECTOPROCTA (BRYOZOA)  (Nitsche 1869)

CLASS PHYLACTOLAEMATA (1 ORDER)

Cristatella, Hydinella, Pectinatella, Lophopus, Lophopodella, Plumatella.

CLASS STENOLAEMATA (1 ORDER)

Actinopora, Crisia, Diaperoecia, Disporella, Idmodronea, Tubulipora.

CLASS GYMNOLAEMATA (2 ORDERS)

Aethozoon, Alcyonidium, Alcyonium, Amathia, Bowerbankia, Flustrellidra, Nolella, Tubiporella, Victorella.

Bugula, Callopora, Carbasea, Cellaria, Clavopora, Conopaeum, Cornucopina, Cribilaria, Cryptosula, Cupuladria, Electra, Eurystomella, Flustra, Hippothoa, Membranipora, Metrabdotus, Microporella, Pentapora, Pherusella, Porella, Pyripora, Rhamphostomella, Schizoporella, Thalamoporella, Tricellaria

 

PHYLUM ENTOPROCTA (Nitsche 1870)

CLASS ENTOPROCTIDA

Urnatella, Loxosoma, Loxosomella, Loxokalypus, Myosoma, Pedicellina, Bartensia, Gonypodaria..

 

PHYLUM CYCLIOPHORA (Funch and Kristensen 2005)

CLASS CYCLIOPHORIDA

Symbion.

 
PLATYZOA (Cavalier-Smith 1998)  

PHYLUM GASTROTRICHA (Metschnikoff 1865)

CLASS GASTROTRICHIDA

Chaetonotus, Tetranchyroderma, Dactylopodula, Macrodasys, Platydasys, Pleurodasys, Turbanella, Urodasys, Neodasys, Aspidophorus, Dasydytes, Lepidodermella.

 

PHYLUM PLATYHELMINTHES (Gegenbaur 1859)

CLASS TURBELLARIA (12 ORDERS)

Amphiscolopus, Convoluta, Haplogonaria, Polychoerus, Catenula, Paracatenula, Dugesia (Planaria), Stenostomum, Haplopharynx, Gnosnesma, Prorhynchus, Macrostomum, Microstomum, Flagellophora, Meara, Nemertoderma, Eurylepta, Hoploplana, Leptoplana, Notoplana, Planocera, Prostheceraeus, Pseudoceros, Stylochus, Thysanozoon, Plagiostomum, Urostoma, Proplicastoma, Nemertoplana,  Octoplana, Taboata, Callastoma, Graffilla, Pterastricola, Kytorhynchus, Mesostoma, Typhlorhynchus, Cheliplana, Cystiplex, Gnathorhynchus, Gyratrix, Temnocephala, Bdelloura, Bipalium, Crenobia, Geoplana, Polycelis, Procotyla.

CLASS MONOGENEA (2 SUBCLASSES, EACH WITH A SINGLE ORDER)

SUBCLASS MONOPISTHOCOTYLEA

Polystoma, Gyrodactylus.

SUBCLASS POLYOPISOTHOCOTYLEA

Diplozoon

CLASS TREMATODA (6 ORDERS DISTRIBUTED THROUGH 2 SUBCLASSES)

SUBCLASS DIGENEA

Echinostoma, Fasciola, Microphallus, Opisthorchis (Clonorchis), Sanguinicola, Schistosoma.

CLASS CESTODA (2 SUBCLASSES)

SUBCLASS CESTODARIA (2 ORDERS)

Amphilina, Gyrocotyl, Gyrometra.

SUBCLASS EUCESTODA (12 ORDERS)

Diphyllobothrium, Taenia, Dipylidium, Hymenolepis, Moniezia, Echinococcus.

 

GNATHIFERA (Kristensen and Funch 2000)

 

PHYLUM GNATHOSTOMULIDA (Ax 1956) or (Sterrer 1972)

CLASS UNNAMED (2 ORDERS)

Gnathostomula, Problognathia, Haplognathia, Pterognathia, Austrognathia.

 

PHYLUM MICROGNATHOZOA (Kristensen and Funch 2000)

CLASS UNNAMED

ORDER LIMNOGNATHIDA Kristensen and Funch 2000

 

PHYLUM SYNDERMATA (Zryavz 2001 or Ahlrichs 1995)) [=ROTIFERA]

CLASS SEISONIDEA (1 ORDER)

Seison.

CLASS BDELLOIDEA (1 ORDER)

Philodina, Embata, Rotaria, Adineta.

CLASS MONOGONATA (3 ORDERS)

Notommata, Proales, Polyarthra, Synchaeta, Chronogaster, Gastropus, Brachionus, Asplanchna, Euchlanis, Keratella, Conochilus, Floscularia, Hexarthra, Testudinella, Stephanoceros, Collotheca, Epiphanes.

CLASS ACANTHOCEPHALA

  SUBCLASS ARCHIACANTHOCEPHALA (4 ORDERS)

Macrocanthorhynchus, Moniliformis, Oligacanthorhynchus.

  SUBCLASS EOCANTHOCEPHALA (2 ORDERS)

Neochinorhynchus, Pallisentis, Bolbosoma.

  SUBCLASS PALEACANTHOCEPHALA (2 ORDERS)

Acanthocephalus, Centrorhynchus, Corynosoma, Echinorhynchus, Leptorhynchoides, Polymorphus.

 

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By Jack R. Holt.  Last revised: 01/31/2012