Xampylodon dentatus (19)
(WOODWARD, 1886)
(WOODWARD, 1886)
Synonyms:
Notidanodon cf. dentatus, Notidanodon dentatus, Notidanus dentatus
Original description species: (WOODWARD, 1886)
Genus: Xampylodon CAPPETTA, MORRISON & ADNET, 2019
Family: Hexanchidae GRAY, 1851
Suborder: Hexanchoidei
Order: Hexanchiformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Original description species: (WOODWARD, 1886)

Genus: Xampylodon CAPPETTA, MORRISON & ADNET, 2019

Family: Hexanchidae GRAY, 1851

Suborder: Hexanchoidei
Order: Hexanchiformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Xenacanthus decheni (30)
(GOLDFUSS, 1847)
(GOLDFUSS, 1847)
Synonyms:
Orthacanthus dechenii, Pleuracanthus decheni, Pleuracanthus (Xenacanthus) decheni
Original description species: (GOLDFUSS, 1847)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (GOLDFUSS, 1847)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus elegans (4)
(TRAQUAIR, 1881)
(TRAQUAIR, 1881)
Synonyms:
Pleuracanthus elegans
Original description species: (TRAQUAIR, 1881)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (TRAQUAIR, 1881)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus gaudryi (2)
(BRONGNIART & SAUVAGE, 1888)
(BRONGNIART & SAUVAGE, 1888)
Synonyms:
Pleuracanthus gaudryi
Original description species: (BRONGNIART & SAUVAGE, 1888)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (BRONGNIART & SAUVAGE, 1888)
Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus humbergensis (5)
HAMPE, 1994
HAMPE, 1994
Original description species:
HAMPE, 1994 
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus laevissimus (15)
(AGASSIZ, 1837)
(AGASSIZ, 1837)
Synonyms:
Compsacanthus major, Dittodus divergens, Expleuracanthus laevissimus, Pleuracanthus erectus, Pleuracanthus laevissimus, Pleuracanthus planus, Pleuracanthus woodwardi, Pleuracanthus (Diplodus) laevissimus, Pternodus productus
Original description species: (AGASSIZ, 1837)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (AGASSIZ, 1837)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus latus (5)
(NEWBERRY & WORTHEN, 1866)
(NEWBERRY & WORTHEN, 1866)
Synonyms:
Diplodus latus, Orthacanthus cf. latus
Original description species: (NEWBERRY & WORTHEN, 1866)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (NEWBERRY & WORTHEN, 1866)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus meisenheimensis (10)
HAMPE, 1994
HAMPE, 1994
Original description species:
HAMPE, 1994 
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus oelbergensis (2)
(FRITSCH, 1890)
(FRITSCH, 1890)
Original description species:
(FRITSCH, 1890) 
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus ossiani (2)
JOHNSON, 1999
JOHNSON, 1999
Synonyms:
Xenacanthus cf. ossiani
Original description species: JOHNSON, 1999
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: JOHNSON, 1999

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus ovalis (8)
(FRITSCH, 1890)
(FRITSCH, 1890)
Synonyms:
Pleuracanthus ovalis
Original description species: (FRITSCH, 1890)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (FRITSCH, 1890)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus parallelus (12)
(FRITSCH, 1890)
(FRITSCH, 1890)
Synonyms:
Pleuracanthus parallelus, Xenacanthus paralellus
Original description species: (FRITSCH, 1890)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (FRITSCH, 1890)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus ragonhai (1)
PAULIV, DIAS, SEDOR & RIBEIRO, 2014
PAULIV, DIAS, SEDOR & RIBEIRO, 2014
Original description species:
PAULIV, DIAS, SEDOR & RIBEIRO, 2014 
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus remigiusbergensis (6)
HAMPE, 1994
HAMPE, 1994
Original description species:
HAMPE, 1994 
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus slaughteri (2)
JOHNSON, 1999
JOHNSON, 1999
Original description species:
JOHNSON, 1999 
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus tenuis (3)
(WOODWARD, 1889)
(WOODWARD, 1889)
Synonyms:
Diplodus tenuis
Original description species: (WOODWARD, 1889)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (WOODWARD, 1889)

Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus tocantinsensis (2)
SANTOS & SALGADO, 1970
SANTOS & SALGADO, 1970
Original description species:
SANTOS & SALGADO, 1970
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenacanthus tridentatus (4)
(HARLTON, 1933)
(HARLTON, 1933)
Synonyms:
Bransonella tridentata
Original description species: (HARLTON, 1933)
Genus: Xenacanthus BEYRICH, 1848
Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Original description species: (HARLTON, 1933)
Genus: Xenacanthus BEYRICH, 1848

Family: Xenacanthidae FRITSCH, 1889
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xenosynechodus egloni (7)
GLIKMAN, 1980
GLIKMAN, 1980
Original description species:
GLIKMAN, 1980 
Genus: Xenosynechodus GLIKMAN, 1980
Family: Xenosynechodontidae GLICKMAN, 1980
Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii

Genus: Xenosynechodus GLIKMAN, 1980

Family: Xenosynechodontidae GLICKMAN, 1980

Order: Xenacanthiformes
Superorder: Xenacanthimorpha
Subclass: Elasmobranchii
Xiaohaizilepis liui (1)
ANDREEV, ZHAO, WANG, SMITH, LI, CUI, ZHU & SANSOM, 2020
ANDREEV, ZHAO, WANG, SMITH, LI, CUI, ZHU & SANSOM, 2020
Original description species:
ANDREEV, ZHAO, WANG, SMITH, LI, CUI, ZHU & SANSOM, 2020 
Genus: Xiaohaizilepis ANDREEV, ZHAO, WANG, SMITH, LI, CUI, ZHU & SANSOM, 2020
Family: Shiqianolepidae SANSOM, ALDRIDGE & SMITH, 2000
Order: Mongolepidida

Genus: Xiaohaizilepis ANDREEV, ZHAO, WANG, SMITH, LI, CUI, ZHU & SANSOM, 2020

Family: Shiqianolepidae SANSOM, ALDRIDGE & SMITH, 2000
Order: Mongolepidida
Xinjiangichthys pluridentatus (4)
WANG, ZHANG, WANG & ZHU, 1998
WANG, ZHANG, WANG & ZHU, 1998
Original description species:
WANG, ZHANG, WANG & ZHU, 1998 
Genus: Xinjiangichthys WANG, ZHANG, WANG & ZHU, 1998
Family: Shiqianolepidae SANSOM, ALDRIDGE & SMITH, 2000
Order: Mongolepidida

Genus: Xinjiangichthys WANG, ZHANG, WANG & ZHU, 1998

Family: Shiqianolepidae SANSOM, ALDRIDGE & SMITH, 2000
Order: Mongolepidida
Xinjiangichthys tarimensis (1)
WANG, ZHANG, WANG & ZHU, 1998
WANG, ZHANG, WANG & ZHU, 1998
Original description species:
WANG, ZHANG, WANG & ZHU, 1998 
Genus: Xinjiangichthys WANG, ZHANG, WANG & ZHU, 1998
Family: Shiqianolepidae SANSOM, ALDRIDGE & SMITH, 2000
Order: Mongolepidida

Genus: Xinjiangichthys WANG, ZHANG, WANG & ZHU, 1998

Family: Shiqianolepidae SANSOM, ALDRIDGE & SMITH, 2000
Order: Mongolepidida
Xiphodolamia barbadica (3)
(CASIER, 1958)
(CASIER, 1958)
Synonyms:
Xenodolamia barbadica
Original description species: (CASIER, 1958)
Genus: Xiphodolamia LEIDY, 1877
Family: Lamnidae BONAPARTE, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Original description species: (CASIER, 1958)

Genus: Xiphodolamia LEIDY, 1877

Family: Lamnidae BONAPARTE, 1835

Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Xiphodolamia ensis (19)
LEIDY, 1877
LEIDY, 1877
Synonyms:
Xyphodolamia ensis
Original description species: LEIDY, 1877
Genus: Xiphodolamia LEIDY, 1877
Family: Lamnidae BONAPARTE, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Original description species: LEIDY, 1877

Genus: Xiphodolamia LEIDY, 1877

Family: Lamnidae BONAPARTE, 1835

Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Xiphodolamia eocaena (32)
(WOODWARD, 1889)
(WOODWARD, 1889)
Synonyms:
Carcharias (Scoliodon) eocaenus, Isurus eocaenus, Oxyrhina eocaena, Oxyrhina zignoi, Rhizoprionodon eocaenus, Xenodolamia eocaena, Xiphodolamia eocenica, Xiphodolamia zignoi
Original description species: (WOODWARD, 1889)
Genus: Xiphodolamia LEIDY, 1877
Family: Lamnidae BONAPARTE, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Original description species: (WOODWARD, 1889)

Genus: Xiphodolamia LEIDY, 1877

Family: Lamnidae BONAPARTE, 1835

Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Xiphodolamia serrata (4)
ADNET & HOSSEINZADEH & ANTUNES & BALBINO & KOZLOV & CAPPETTA, 2009
ADNET & HOSSEINZADEH & ANTUNES & BALBINO & KOZLOV & CAPPETTA, 2009
Original description species:
ADNET & HOSSEINZADEH & ANTUNES & BALBINO & KOZLOV & CAPPETTA, 2009 
Genus: Xiphodolamia LEIDY, 1877
Family: Lamnidae BONAPARTE, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Genus: Xiphodolamia LEIDY, 1877

Family: Lamnidae BONAPARTE, 1835

Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii
Xystracanthus arcuatus (1)
LEIDY, 1859
LEIDY, 1859
Xystrogaleus cappettai (3)
ADNET, 2006
ADNET, 2006
Original description species:
ADNET, 2006 
Genus: Xystrogaleus ADNET, 2006
Family: Triakidae GRAY, 1851
Order: Carcharhiniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Genus: Xystrogaleus ADNET, 2006

Family: Triakidae GRAY, 1851

Order: Carcharhiniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii