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Polyplacophora (chiton)

Polyplacophora

Taxonomy
Polyplacophora was named by de Blainville (1816) [also attributed to Gray 1821]. It is extant.

It was reranked as the order Polyplacophora by Martin (1904).

It was assigned to Amphineura by Martin (1904); to Mollusca by Barnes (1998), Wells and Houston (2001), Sepkoski (2002); and to Serialia by Giribet et al. (2006).

Synonyms
Synonymy list
YearName and author
1816Polyplacophora de Blainville
1904Polyplacophora Martin p. 270
1998Polyplacophora Barnes
2001Polyplacophora Wells and Houston p. 19
2002Polyplacophora Sepkoski
2006Polyplacophora Giribet et al. p. 7725

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RankNameAuthor
kingdomAnimalia()
—Bilateria
—EubilateriaAx 1987
—Protostomia
—Spiralia
RankNameAuthor
superphylumLophotrochozoa
phylumMollusca
—Serialia
classPolyplacophorade Blainville 1816
classPolyplacophorade Blainville 1816

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Cl. Polyplacophora de Blainville 1816 [chiton]
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Fm. †Dycheiidae Pojeta et al. 2010
+
G. †Dycheia Pojeta and Derby 2007
+
†Dycheia shergoldi Pojeta and Derby 2007
G. †Paradycheia Pojeta et al. 2010
+
†Paradycheia dorisae Pojeta et al. 2010
G. †Emo Sutton et al. 2025
+
†Emo vorticaudum Sutton et al. 2025
Fm. †Heloplacidae Cherns 2004
+
G. †Acaenoplax Sutton et al. 2001
+
†Acaenoplax hayae Sutton et al. 2001
G. †Enetoplax Cherns 1998
+
†Enetoplax decora Cherns 1998
G. †Heloplax Cherns 1998
+
†Heloplax papilla Cherns 1998
Or. †Multiplacophora Hoare and Mapes 1995
+
Fm. †Hercolepadidae Dzik 1986
+
G. †Protobalanus Whitfield 1888
+
†Protobalanus spinicoronatus Vinther et al. 2012
G. †Polysacos Vendrasco et al. 2004
+
†Polysacos vickersianum Vendrasco et al. 2004
Fm. †Strobilepidae Hoare and Mapes 1995
+
G. †Diadeloplax Hoare and Mapes 1995
+
†Diadeloplax antiqua Howse 1848
+
Invalid names: Chitonellus distortus Kirkby 1859 [synonym], Chitonellus hancockianus Kirkby 1859 [synonym]
†Diadeloplax apiculatus Hanger et al. 2000
G. †Hannestheronia Vinther et al. 2012
+
†Hannestheronia australis Vinther et al. 2012
G. †Strobilepis Hall and Clarke 1888
+
†Strobilepis spinigera Clarke 1888
+
Invalid names: Lobarochiton anomalus Rowley 1908 [synonym]
Invalid names: Strobilepida Hoare and Mapes 1995 [empty]
Subcl. Neoloricata Bergenhayn 1955
+
Fm. Chaetopleuridae Plate 1899
+
G. Calloplax Thiele 1909
+
†Calloplax roederi Vendrasco et al. 2022
G. Chaetopleura Shuttleworth 1853
+
Subg. †Chaetopleura (Pallochiton) Dall 1879
†Chaetopleura gemma Carpenter 1879 [gem chiton]
G. Dinoplax Dall 1882
+
Dinoplax gigas Gmelin 1791
Or. Chitonida Thiele 1909
+
Subor. Acanthochitonina Bergenhayn 1930
+
Fm. Acanthochitonidae Pilsbry 1893
+
G. Acanthochitona Gray 1821 [glass-hair chiton]
Subfm. Acanthochitoninae Pilsbry 1893
G. †Bassethullia Pilsbry 1928
G. Craspedochiton Shuttleworth 1853
G. Cryptochiton Middendorff 1847
G. Cryptoconchus Burrow 1815
G. Cryptoplax Blainville 1818
G. †Leptoplax Carpenter 1882
G. Notoplax Adams 1861
Invalid names: Callistochitoninae Berry 1922 [empty]
Fm. Chitonidae Rafinesque 1815
+
Subfm. Acanthopleurinae Thiele 1910
G. Chiton Linnaeus 1758
Subfm. †Chitoninae Linnaeus 1758
G. Onithochiton Gray 1847
Invalid names: Toniciinae [empty]
Fm. †Ischnochitonidae Dall 1889
+
Subfm. †Callochitoninae
Subfm. †Chaetopleurinae
G. Cyanoplax Pilsbry 1892
G. Lepidozona Pilsbry 1892
Subfm. †Schizoplacinae
G. Stenoplax Carpenter 1879
G. †Stenosemus Middendorff 1847
G. Tonicella Carpenter 1873
G. Tripoplax Berry 1919
Fm. Loricidae Iredale and Hull 1923
+
G. Lorica Adams and A. 1852
Fm. Callistoplacidae Dall 1879
+
G. Callistochiton Carpenter 1879
+
†Callistochiton decoratus Pilsbry 1896
Callistochiton palmulatus Dall 1879 [palmate chiton]
G. Ceratozona Dall 1882
G. †Middendorfia Dall 1879
+
†Middendorfia corrugis Boettger 1869
+
Invalid names: Chiton etrechyensis de Rochebrune 1882 [synonym], Tonicia mammillata de Rochebrune 1882 [synonym]
G. Nuttallina Dall 1871
+
Nuttallina californica Reeve 1847 [scaly chiton]
+
Invalid names: Nuttallina fluxa Carpenter 1864 [synonym]
Subor. †Cymatochitonina Sirenko and Starobogatov 1977
+
Fm. †Cymatochitonidae Sirenko and Starobogatov 1977
+
G. †Cymatochiton Dall 1882
+
†Cymatochiton texanus Girty 1909
Fm. †Gryphochitonidae Pilsbury 1900
+
G. †Aaptochiton Hoare and Karasawa 2008
+
†Aaptochiton pustulosus Hoare and Karasawa 2008
G. †Chauliochiton Hoare and Smith 1984
+
†Chauliochiton knighti Hoare and Smith 1984
G. †Chonechiton Carpenter 1882
+
†Chonechiton viseticola de Ryckholt 1845
G. †Gryphochiton Gray 1847
+
†Gryphochiton asamiae Hoare and Karasawa 2008
†Gryphochiton distinctus Hoare et al. 2002
†Gryphochiton girtyi Hoare and Smith 1984
†Gryphochiton planoplata Hanger et al. 2000
Fm. †Lekiskochitonidae Smith and Hoare 1987
+
G. †Lekiskochiton Hoare and Smith 1984
+
†Lekiskochiton crassus Mazaev 2024
†Lekiskochiton fornicis Hoare and Smith 1984
Subor. Ischnochitonina Bergenhayn 1930
+
Fm. Mopaliidae Dall 1889
+
G. Amicula Gray 1847
G. Katharina Gray 1847
+
†Katharina tunicata Wood 1815 [black katy]
G. Mopalia Gray 1847
+
Subg. Mopalia (Dendrochiton) Berry 1911
†Mopalia acuta Carpenter 1855
†Mopalia ciliata Sowerby 1840 [hairy chiton]
†Mopalia hindsii Sowerby 1847
Mopalia imporcata Carpenter 1864
†Mopalia lignosa Gould 1846 [woody chiton]
Mopalia lowei Pilsbry 1918
†Mopalia muscosa Gould 1846 [mossy mopalia]
†Mopalia sinuata Carpenter 1864
G. Placiphorella Carpenter 1879
+
†Placiphorella velata Carpenter 1879 [veiled chiton]
G. Plaxiphora Gray 1847
Invalid names: Heterochitoninae [empty], Katharininae [empty], Mopaliinae [empty]
+
†Pterygochiton distefanoi Fucini 1912
†Pterygochiton liasinus Eudes-Deslongchamps 1864
†Pterygochiton mirificus Fucini 1912
†Pterygochiton terquemii Eudes-Deslongchamps 1859
Fm. Schizochitonidae Dall 1885
+
G. †Aulacochiton Shuttleworth
+
†Aulacochiton praecursor Smith et al. 1968
G. Loricella Pilsbry 1893
+
Loricella angasi Adams 1864
G. †Oochiton
G. Schizochiton Gray 1847
+
Schizochiton incisus Sowerby 1841
Subor. †Lepidopleurina Thiele 1910
+
Fm. †Acutichitonidae Hoare et al. 1983
+
G. †Acutichiton Hoare et al. 1972
+
†Acutichiton gracilis Hoare et al. 2002
†Acutichiton nevadensis Hoare et al. 2002
†Acutichiton pannuceus Hoare and Mapes 1985
†Acutichiton pyrmidalus Hoare et al. 1972
G. †Arcochiton Hoare and Sturgeon 1976
+
†Arcochiton raymondi Hoare and Sturgeon 1976
†Arcochiton richardsoni Hoare et al. 2002
†Arcochiton soccus Hanger et al. 2000
G. †Kraterochiton Hoare 2000
+
G. †Soleachiton Hoare and Smith 1984
+
†Soleachiton yochelsoni Hoare and Smith 1984
+
G. †Choriplax Pilsbry 1894
+
G. †Plasiochiton Hoare 2000
+
†Plasiochiton curiosus Hoare 2000
Fm. †Crassitudochitonidae Hoare and Karasawa 2008
+
G. †Crassitudochiton Hoare and Karasawa 2008
+
†Crassitudochiton plakos Hoare and Karasawa 2008
Fm. †Glyptochitonidae Starobogatov and Sirenko 1975
+
G. †Glyptochiton de Koninck 1883
+
†Glyptochiton cordifer de Koninck 1844
Fm. Hanleyidae Bergenhayn 1955
+
G. Hanleya Gray 1857
+
†Hanleya hanleyi Bean 1844
G. †Hemiarthrum Carpenter 1876
G. †Homeochiton Hanger et al. 2000
+
†Homeochiton triangulus Hanger et al. 2000
Fm. †Lepidopleuridae Pilsbry 1892
+
G. †Asketochiton Hoare and Sabattini 2000
+
†Asketochiton chubutensis Hoare and Sabattini 2000
G. †Camptochiton Debrock et al. 1984
G. †Colapterochiton Hoare and Mapes 1985
+
†Colapterochiton decorus Hoare and Mapes 1985
G. †Coryssochiton Debrock et al. 1984
G. †Glaphurochiton Raymond 1910
+
+
Invalid names: Helminthochiton concinnus Richardson 1956 [synonym]
G. †Hadrochiton Hoare 2000
+
†Hadrochiton pileus Hoare 2000
G. †Lobarochiton Hoare 1976
G. Oldroydia Dall 1894 [Oldroyd's thick chiton]
G. †Pedanochiton Debrock et al. 1984
G. †Pileochiton Debrock et al. 1984
G. †Schematochiton Hoare 2002
+
G. †Stegochiton Hoare and Smith 1984
+
†Stegochiton coxi Hoare and Smith 1984
†Stegochiton onerosus Hoare and Smith 1984
Fm. Leptochitonidae Dall 1889
+
G. †Gifuchiton Hoare and Karasawa 2008
+
†Gifuchiton pentagonus Hoare and Karasawa 2008
G. Leptochiton Gray 1847
+
Subg. †Leptochiton (Parachiton) Thiele 1909
†Leptochiton algesirensis Capellini 1859
+
Invalid names: Lepidopleurus (Leptochiton) algesirensis Angelo and Palazzi 1989 [synonym]
†Leptochiton cancellatus Sowerby 1840
†Leptochiton clarki Berry 1922
†Leptochiton terryiverseni Hybertsen and Kiel 2018
Subfm. Leptochitoninae Dall 1889
+
G. Lepidopleurus Gray 1847
+
Invalid names: Lepidochiton Gray 1847 [synonym], Rhombichiton Dekoninck 1883 [synonym]
G. †Pterochiton Carpenter 1882
+
†Pterochiton eburonicus de Ryckholt 1845
†Pterochiton newelli Smith 1976
†Pterochiton spatulatus Hoare et al. 1972
Fm. †Ochmazochitonidae Hoare and Smith 1984
+
G. †Ochmazochiton Hoare and Smith 1984
+
†Ochmazochiton comptus Hoare and Smith 1984
†Ochmazochiton uralensis Mazaev 2024
G. †Pyknochiton Hoare 2000
+
†Pyknochiton lunatus Hoare 2000
G. †Loboarochiton Hoare 1976
+
†Proleptochiton laterodepressus Bergenhayn 1945
Invalid names: Abyssochitonidae [empty], Chitonina Thiele 1910 [empty], Cryptoplacidae [empty], Lepidopleurida Thiele 1910 [empty], Xylochitonidae Gowlett-Holmes and A.M. 1992 [empty]
G. †Prisochiton Dall 1881
G. Trachydermon Carpenter 1864
Invalid names: Amphineura [synonym], Mesoplacophora [empty]
Diagnosis
No diagnoses are available
Measurements
No measurements are available
Composition: aragonitec
Environment: marine, brackishc
Locomotion: facultatively mobilec
Attached: yesc
Life habit: epifaunalc
Diet: grazerc
Vision: limitedc
Comments: LIFE HISTORY: Surficial, fully motile slow/facultatively motile unattached, surface deposit feeding according to Bambach et al (2007).c
Created: 2007-09-07 09:30:10
Modified: 2010-02-15 05:49:47
Source: c = class
Reference: Kiessling 2003

Age range

Maximum range based only on fossils: base of the Trempealeauan to the top of the Holocene or 490.20000 to 0.00000 Ma
Minimum age of oldest fossil (stem group age): 486.85 Ma

Collections (281 total)

Oldest occurrences

Time interval Ma Country or state Original ID and collection number
Trempealeauan490.2 - 486.85USA (Missouri) Paradycheia dorisae (98337 98338 98339)
Blackhillsian475.3 - 471.3USA (Texas) Polyplacophora indet. (210611)
Late/Upper Ordovician458.2 - 443.1USA (Alaska) Prisochiton sp. (100882)
Wenlock432.9 - 426.7United Kingdom Acaenoplax hayae, Emo vorticaudum (68060)
Homerian430.6 - 426.7Sweden (Gotland) Heloplax papilla, Enetoplax decora (13635)
Ludlow426.7 - 422.7USA (California) Gryphochitonidae indet. (229624)
Eifelian393.47 - 387.95South Africa Hannestheronia australis (35597)
Givetian387.95 - 382.31USA (Ohio) Protobalanus spinicoronatus (81857)
Givetian387.95 - 382.31USA (Pennsylvania) Plasiochiton curiosus (50947)
Middle Givetian385.9 - 383.4USA (New York) Strobilepis spinigera (154364)
Late/Upper Famennian365.2 - 358.86USA (Missouri) Platyceras anomalum (233225)
Early/Lower Mississippian358.86 - 346.7USA (Indiana) Polysacos vickersianum (91434)
Chadian346.7 - 339.9Czechia Lepidopleurus laterodepressus (38086 38088 38090)
Meramecian342.9 - 335.4Canada (Alberta) Chiton carbonarius (62396)
Morrowan323.4 - 318.6USA (Oklahoma) Colapterochiton decorus (79329)
Moscovian315.2 - 307.0USA (Texas) Colapterochiton decorus (79328)
Kashirian - Myachkovian313.8 - 307.0USA (Texas) Camptochiton squarrosus, Coryssochiton parallelus, Pedanochiton discomptus, Pileochiton cancellus, Arcochiton raymondi, Acutichiton pyrmidalus, Pterochiton spatulatus (41873)
Desmoinesian312.8 - 306.0USA (Oklahoma) Glaphurochiton sp. (91530)
Desmoinesian312.8 - 306.0USA (Ohio) Arcochiton raymondi, Acutichiton pyrmidalus, Pterochiton spatulatus, Pterochiton carbonarius (71963) Pterochiton carbonarius (72004 79324 79327)
Desmoinesian - Gzhelian312.8 - 298.9USA (Illinois) Chiton carbonarius (128873)