Synonyms: Triakis angustidens
Original description species: (Cappetta, 1973)
Genus: Iago Compagno & Springer, 1971
Family: Triakidae Gray, 1851
Order: Carcharhiniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Leder, 2013
Genus: Iago Compagno & Springer, 1971
Family: Triakidae Gray, 1851
Order: Carcharhiniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Triakis aff. costamagnai, Triakis cf. costamagnai, Triakis costamagnai
Original description species: (Cappetta & Nolf, 1991)
Genus: Iago Compagno & Springer, 1971
Family: Triakidae Gray, 1851
Order: Carcharhiniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Genus: Iago Compagno & Springer, 1971
Family: Triakidae Gray, 1851
Order: Carcharhiniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Rhinobatos beurleni
Original description species: (Santos, 1968)
Genus: Iansan Brito & Seret, 1996
Family: Rhinobatidae Bonaparte, 1835
Order: Rhinopristiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Genus: Iberolepis Mader, 1986
Subclass: Elasmobranchii

Original description species: Kriwet, Nunn & Klug, 2009
Genus: Iberotrygon Kriwet, Nunn & Klug, 2009
Family: incert. fam.
Order: Sclerorhynchiformes
Superorder: Pristiorajea
Subclass: Elasmobranchii

Synonyms: Igdabatis cf. indicus
Original description species: Prasad & Cappetta, 1993
Genus: Igdabatis Cappetta, 1972
Family: Myliobatidae Bonaparte, 1838
Order: Myliobatiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Blanco, 2019
Genus: Igdabatis Cappetta, 1972
Family: Myliobatidae Bonaparte, 1838
Order: Myliobatiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Igdabatis cf. sigmodon
Original description species: Cappetta, 1972
Genus: Igdabatis Cappetta, 1972
Family: Myliobatidae Bonaparte, 1838
Order: Myliobatiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Pristiophorus ensifer, Trygon ensifer
Original description species: (Davis, 1888)
Genus: Ikamauius Keyes, 1979
Family: Pristiophoridae Bleeker, 1859
Order: Pristiophoriformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Feichtinger, Pollerspöck, Harzhauser, Auer, Ćorić, Kranner, Beaury & Guinot, 2024
Genus: Incognitorapax Feichtinger, Pollerspöck, Harzhauser, Auer, Ćorić, Kranner, Beaury & Guinot, 2024
Family: Etmopteridae Fowler, 1934
Order: Squaliformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Iniopera cf. richardsoni
Original description species: Zangerl & Case, 1973
Genus: Iniopera Zangerl & Case, 1973
Family: Sibyrhynchidae Zangerl & Case, 1973
Order: Iniopterygiformes
Subclass: Holocephali

Synonyms: Iniopteryx cf. rushlaui
Original description species: Zangerl & Case, 1973
Genus: Iniopteryx Zangerl & Case, 1973
Family: Iniopterygidae Zangerl & Case, 1973
Order: Iniopterygiformes
Subclass: Holocephali

Original description species: Zangerl & Case, 1973
Genus: Iniopteryx Zangerl & Case, 1973
Family: Iniopterygidae Zangerl & Case, 1973
Order: Iniopterygiformes
Subclass: Holocephali

Original description species: Zangerl & Case, 1973
Genus: Inioxyele Zangerl & Case, 1973
Family: Sibyrhynchidae Zangerl & Case, 1973
Order: Iniopterygiformes
Subclass: Holocephali

Original description species: Ivanov, Nestell & Nestell, 2012
Genus: Isacrodus Ivanov, Nestell & Nestell, 2012
Family: Jalodontidae Ginter, Hairapetian & Klug, 2002
Order: Jalodontiformes
Subclass: Elasmobranchii

Original description species: Khamha, Cuny & Lauprasert, 2016
Genus: Isanodus Cuny, Suteethorn, Kamha, Buffetaut & Philippe, 2006
Family: fam. indet
Superfamily: Hybodontoidea
Order: Hybodontiformes
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Cuny, Suteethorn, Kamha, Buffetaut & Philippe, 2006
Genus: Isanodus Cuny, Suteethorn, Kamha, Buffetaut & Philippe, 2006
Family: fam. indet
Superfamily: Hybodontoidea
Order: Hybodontiformes
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Ischyodus cf. acutus, Ischyodus (Chimaera) acutus
Original description species: Von Meyer, 1859
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera beaumonti, Chimaera (Ischyodon) beaumontii, Ischyodon beaumontii, Ischyodus beaumontii, Ischyodus cf. beaumonti, Ischyodus rigauxi
Original description species: (Egerton, 1843)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Ischyodus aff. bifurcatus, Ischyodus cf. bifurcatus
Original description species: Case, 1978
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Bayer, 1905
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera (Ganodus) colei, Ganodus colei
Original description species: (Agassiz, 1843)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Callorhinchus crassus, Callorhynchus crassus
Original description species: (Woodward & Withe, 1930)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera curvidens, Chimaera neglecta, Chimaera (Ganodus) curvidens, Chimaera (Ganodus) neglecta, Ganodus curvidens, Ganodus dentatus, Ganodus neglectus, Ischyodus neglectus
Original description species: (Egerton, 1843)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Ischyodus cf. dolloi, Ischyodus zinsmeisteri
Original description species: Leriche, 1902
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera dufrenoyi, Chimaera (Ischyodon) dufrenoyi, Ischyodon dufrenoyi, Ischyodon dufrenoyii
Original description species: (Egerton, 1843)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera (Ischyodon) dutertrii, Ischyodon dutertrei, Ischyodon dutertrii
Original description species: Egerton, 1843
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera egertoni, Chimaera egertonii, Chimaera schübleri, Chimaera (Ischyodon) egertoni, Ischyodon egertoni, Ischyodon egertonii, Ischyodus cf. egertoni, Ischyodus cf. schuebleri, Ischyodus sauvagei, Ischyodus schübleri, Ischyodus schuebleri, Ischyodus suevicus, Ischyodus suprajurensis
Original description species: (Buckland, 1835)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera emarginata, Chimaera (Ischyodon) emarginata, Chimaera (Ischyodon) tessoni, Ganodus emarginatus, Ganodus oweni, Ischyodon emarginata, Ischyodon emarginatus, Ischyodon tessonii, Ischyodus tessoni, Leptacanthus serratus
Original description species: (Egerton, 1843)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Aletodus ferrugines
Original description species: Riess, 1887
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Newton, 1878
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Ischyodon johnsonii
Original description species: Agassiz, 1843
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Newton, 1878
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Chapman & Pritchard, 1907
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Averianov, 1992
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera personati
Original description species: (Quenstedt, 1858)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Elasmodus planus
Original description species: Newton, 1878
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera (Ischyodon) quenstedti
Original description species: (Wagner, 1857)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Hoganson & Erickson, 2005
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Ischyodus (Chimaera) rostratus
Original description species: Von Meyer, 1859
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera (Ischyodon) brevirostris, Ischyodon brevirostris, Ischyodus bouchardi, Ischyodus brevirostris, Ischyodus cf. brevirostris, Ischyodus cf. thurmanni
Original description species: Picet & Campiche, 1858
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Chimaera townsendi, Chimaera townsendii, Chimaera (Ischyodon) townsendii, Ischyodon townsendii, Ischyodus cf. townsendi, Ischyodus townsendii, Ischyodus townshendi
Original description species: (Buckland, 1835)
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Original description species: Case, 1991
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Ischyodus yanshini
Original description species: Averianov, 1991
Genus: Ischyodus Egerton, 1843
Family: Edaphodontidae Owen, 1846
Order: Chimaeriformes
Subclass: Holocephali

Synonyms: Ischyrhiza aff. avonicola, Ischyrhiza cf. avonicola, Ischyrhiza germaniae, Ischyrhiza monasterica, Sclerorhynchus germaniae, Texatrygon avonicola
Original description species: Estes, 1964
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Case, 1987
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: (Philippi, 1887)
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Case, Schwimmer, Borodin & Leggett, 2001
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Cappetta, 1975
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Ischyrhiza aff. mira, Ischyrhiza antiqua, Ischyrhiza cf. mira, Ischyrhiza mira mira, Onchosaurus (Ischyrhiza) antiquus
Original description species: Leidy, 1856
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Slaughter & Steiner, 1968
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Ischirhiza nigeriensis, Marckgrafia nigeriensis
Original description species: (Tabaste, 1963)
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Clark, 1895
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: (Slaughter & Schneider, 1968)
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Nessov, 1997
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Cappetta, 1981
Genus: Ischyrhiza Leidy, 1856
Family: Sclerorhynchidae Cappetta, 1974
Suborder: Sclerorhynchoidei
Order: Rajiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Dasyatis globidens
Original description species: (Arambourg, 1952)
Genus: Ishaquia Noubhani & Cappetta, 1995
Family: Dasyatidae Jordan & Gilbert, 1879
Order: Myliobatiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isistius aff. brasiliensis-f
Original description species: (Quoy & Gaimard, 1824)
Genus: Isistius Gill, 1865
Family: Dalatiidae Gray, 1851
Order: Squaliformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Genus: Isistius Gill, 1865
Family: Dalatiidae Gray, 1851
Order: Squaliformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Centrina dertonensis, Isistius aff. triangulus, Isistius cf. triangulus, Scymnorhinus triangulus, Scymnus triangulus
Original description species: (Probst, 1879)
Genus: Isistius Gill, 1865
Family: Dalatiidae Gray, 1851
Order: Squaliformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Centrina trituratus, Corax trituratus, Isistius aff. trituratus, Isistius cf. trituratus, Scymnus trituratus
Original description species: (Winkler, 1874)
Genus: Isistius Gill, 1865
Family: Dalatiidae Gray, 1851
Order: Squaliformes
Superorder: Squalomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Lamiostoma affinis, Lamna affinis, Odontaspis (Synodontaspis) affinis
Original description species: (Casier, 1946)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Lamiostoma bajarunasi
Original description species: (Glikman & Zhelezko, 1985)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Anomotodon biflexus, Oxyrhina biflena, Oxyrhina biflexa
Original description species: (Rogovich, 1861)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isurolamna rupeliensis, Isurus gracilis, Lamiostoma gracilis, Lamiostoma rupeliensis, Lamna cf. rupeliensis, Lamna hasloensis, Lamna rupeliensis, Otodus rupeliensis, Oxyrhina gracilis, Rhizoquadrangulus rupeliensis
Original description species: (Le Hon, 1871)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isurolamna aff. inflata, Lamna inflata, Lamna lerichei inflata, Lamna vincenti inflata
Original description species: (Leriche, 1905)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Lamiostoma menneri
Original description species: (Glikman & Zhelezko, 1985)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isurus schoutedeni (Herman 1973), Oxyrhina shoutedeni
Original description species: (Herman, 1973)
Genus: Isurolamna Cappetta, 1976
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Oxyrhina biconvexus
Original description species: (Ameghino, 1906)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isurus cf. desori, Isurus desorii, Isurus desorii desorii, Isurus (Oxyrhina) desori, Lamiostoma desori, Lamna desori, Lamna inaequilateralis, Lamna lyellii, Oxyrhina aff. desori, Oxyrhina cf. desori, Oxyrhina desori, Oxyrhina desorii
Original description species: (Agassiz, 1843)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Oxyrhina incerta
Original description species: (Michelotti, 1861)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: (Daimeries, 1888)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Otodus microtus
Original description species: (Rogovich, 1861)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Lamna aff. minuta, Oxyrhina minuta
Original description species: (Agassiz, 1843)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Saito, 1961
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Rafinesque, 1810
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isuropsis mako-f, Isurus aff. oxyrinchus-f, Isurus cf. oxyrhinchus-f, Isurus cf. oxyrhynchus-f, Isurus cf. oxyrinchus-f, Isurus cf. spallanzani-f, Isurus oxyrhynchus-f, Isurus spallanzani-f, Isurus spallanzanii-f, Lamna spallanzanii-f, Oxyrhina gomphodon-f, Oxyrhina oxyrhynchus-f, Oxyrhina spallanzani-f, Oxyrhina spallanzanii-f
Original description species: Rafinesque, 1810
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isurus cf. paucus-f
Original description species: Guitart Manday, 1966
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Mehrotra, Mishra & Srivastava, 1973
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Oxyrhina recta
Original description species: (Davis, 1888)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Anotodus agassizii, Anotodus cf. agassizii, Anotodus retroflexus, Isurus aff. retroflexus, Isurus retoflexus, Isurus retroflexa, Oxyrhina agassizii, Oxyrhina complanata, Oxyrhina retroflexa
Original description species: (Agassiz, 1838)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Oxyrrhina rhenana
Original description species: (Jaekel, 1898)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Otodus salentinus
Original description species: (Costa, 1850)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Isurus sillimanii, Oxyrhina aff. sillimani, Oxyrhina cf. sillimani, Oxyrhina sillimani, Oxyrhina sillimanii
Original description species: (Gibbes, 1847)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Synonyms: Carcharias escheri, Carcharias subserratus, Carcharocles subserratus, Carcharodon escheri, Carcharodon microdon, Carcharodon subserratus, Carcharomodus escheri, Cosmopolitodus escheri, Isurus escheri, Isurus hastalis escheri, Lamna obliqua subserrata, Macrorhizodus escheri, Otodus subserratus, Oxyrhina escheri, Oxyrhina hastalis escheri
Original description species: (Agassiz, 1843)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: (M’coy in Tenison-Woods, 1862)
Genus: Isurus Rafinesque, 1810
Family: Lamnidae Bonaparte, 1835
Order: Lamniformes
Superorder: Galeomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii

Original description species: Silva Santos, 1990
Genus: Itapyrodus Silva Santos, 1990
Family: Petalodontidae Newberry & Worthen, 1866
Order: Petalodontiformes
Subclass: Euchondrocephali

Original description species: Karatajute-Talimaa, 1997
Genus: Ivanelepis Karatajute-Talimaa, 1997
Family: incert. fam.
Order: incert. sedis
Subclass: Elasmobranchii

Synonyms: Raja mucronata
Original description species: (Arambourg, 1952)
Genus: Ixobatis Noubhani & Cappetta, 1995
Family: incert. fam.
Order: Myliobatiformes
Superorder: Batomorphii
Subcohort: Neoselachii
Cohort: Euselachii
Subclass: Elasmobranchii