- Yaadia, Genus Yaadia Crickmay, 1930 (STEINMANELLIDAE) (FOSSIL)
- Yabea, Genus Yabea Hayami, 1965 (CARDIIDA (UNASSIGNED)) (FOSSIL)
- yabeaformis, Bungoella yabeaformis Tashiro & al. 1985 † - (CARDIIDA (UNASSIGNED)) (FOSSIL)
- yabehisakatsui, Megastomia yabehisakatsui (S. Nomura, 1936) - (PYRAMIDELLIDAE)
- yabei, Bellerophon yabei Murata, 1969 † - (BELLEROPHONTIDAE) (FOSSIL)
- yabei, Mitrella yabei S. Nomura, 1935 - (COLUMBELLIDAE)
- yabei, Conus yabei S. Nomura, 1935 † - (CONIDAE) (FOSSIL)
- yabei, Cymatoceras yabei H. Ozaki & Katto, 1956 † - (CYMATOCERATIDAE) (FOSSIL)
- yabei, Epitonium yabei S. Nomura, 1937 - (EPITONIIDAE)
- yabei, Helicotoma yabei Kobayashi, 1930 † - syn of: Scalites kanesi Kobayashi, 1930 † - (HELICOTOMIDAE) (FOSSIL)
- yabei, Lophospira yabei Endo, 1935 † - syn of: Lophospira rectistriata W.J. Raymond, 1908 † - (LOPHOSPIRIDAE) (FOSSIL)
- yabei, Akasakiella yabei (I. Hayasaka, 1943 †) - (MURCHISONIIDAE) (FOSSIL)
- yabei, Sinum yabei Y. Otuka, 1934 † - syn of: Sinum ineptum Yokoyama, 1924 † - (NATICIDAE) (FOSSIL)
- yabei, Ankinatsytes yabei M. Collignon, 1965 † - (NOSTOCERATIDAE) (FOSSIL)
- yabei, Spiromphalus yabei I. Hayasaka, 1939 † - (ORTHONEMIDAE) (FOSSIL)
- yabei, Penitella yabei M. Yokoyama, 1924 - syn of: Penitella gabbii (G.W. Tryon, 1863) - (PHOLADIDAE)
- yabei, Jouannetia yabei M. Yokoyama, 1924 - syn of: Penitella gabbii (G.W. Tryon, 1863) - (PHOLADIDAE)
- yabei, Brachytoma yabei E.W. Vredenburg, 1921 † - (PSEUDOMELATOMIDAE) (FOSSIL)
- yabei, Gymnarus yabei (T. Nagao, 1939 †) - (PUGNELLIDAE) (FOSSIL)
- yabei, Babella yabei (S. Nomura, 1936) - (PYRAMIDELLIDAE)
- yabei, Ptycheulimella yabei (S. Nomura, 1939) - (PYRAMIDELLIDAE)
- yabei, Scalites yabei Kobayashi, 1930 † - syn of: Scalites kanesi Kobayashi, 1930 † - (RAPHISTOMATIDAE) (FOSSIL)
- yabei, Turbo yabei S. Nomura & N. Zinbo, 1936 † - syn of: Carswellena gemmatus (L.A. Reeve, 1848) - (TURBINIDAE) (FOSSIL)
- yabei, Ussurites yabei Diener, 1915 † - (USSURITIDAE) (FOSSIL)
- yabei, Cnesterium yabei (M. Yokoyama, 1924 †) - (YOLDIIDAE) (FOSSIL)
- yabei permariella, Babella yabei permariella S. Nomura, 1938 - (PYRAMIDELLIDAE)
- Yabeiceras, Genus Yabeiceras Tokunaga & Shimizu, 1926 (COLLIGNONICERATIDAE) (FOSSIL)
- Yabepecten, Genus Yabepecten O. Masuda, 1963 (PECTINIDAE)
- yabeshigerui, Baylea yabeshigerui O. Kobayashi, 1931 † - (GOSSELETINIDAE) (FOSSIL)
- yachihoensis, Edmondia yachihoensis A.W. Grabau, 1934 † - (EDMONDIIDAE) (FOSSIL)
- yacobi, Lithophaga yacobi F.P. Jousseaume in É. Lamy, 1919 - syn of: Rhomboidella obesa K.W. Ockelmann, 1983 - (MYTILIDAE)
- Yacutolituus, Genus Yacutolituus Missarzhevsky , 1974 (INFLATICORNIDAE) (FOSSIL)
- yadai, Bathybuccinum yadai K. Fraussen & M. Chino, 2009 - (BUCCINIDAE)
- yadai, Tateshia yadai S. Kosuge, 1986 - (MARGINELLIDAE)
- yadkinensis, Unio yadkinensis I. Lea, 1872 - syn of: Unio abbevillensis I. Lea, 1857 - (UNIONIDAE)
- yaegashii, Praecaprotina yaegashii (Yehara 1920) † - (POLYCONITIDAE) (FOSSIL)
- yaekoae, Mitra fulgurita yaekoae (T. Habe & S. Kosuge, 1966) - (MITRIDAE)
- yaeyamaensis, Satsuma yaeyamaensis (H.A. Pilsbry, 1894) - syn of: Satsuma yaeyamensis (H.A. Pilsbry, 1894) - (CAMAENIDAE)
- yaeyamaensis, Zaptyx yaeyamaensis (H.A. Pilsbry, 1905) - syn of: Zaptyx yaeyamensis (H.A. Pilsbry, 1905) - (CLAUSILIIDAE)
- yaeyamaensis, Enteroplax yaeyamaensis T. Habe & M. Chinen, 1974 - (STROBILOPSIDAE)
- yaeyamana, Elysia yaeyamana K. Baba, 1936 - (PLAKOBRANCHIDAE)
- yaeyamensis, Satsuma yaeyamensis (H.A. Pilsbry, 1894) - (CAMAENIDAE)
- yaeyamensis, Kaliella yaeyamensis H.A. Pilsbry, 1901 - syn of: Liardetia yaeyamensis (H.A. Pilsbry, 1901) - (CHRONIDAE)
- yaeyamensis, Zaptyx yaeyamensis (H.A. Pilsbry, 1905) - (CLAUSILIIDAE)
- yaeyamensis, Platyrhaphe hirasei yaeyamensis J.T. Kuroda, 1960 - (CYCLOPHORIDAE)
- yaeyamensis, Discodoris yaeyamensis K. Baba, 1936 - (DISCODORIDIDAE)
- yaeyamensis, Liardetia yaeyamensis (H.A. Pilsbry, 1901) - (EUCONULIDAE)
- yaeyamensis, Aphanoconia yaeyamensis (H.A. Pilsbry, 1901) - (HELICINIDAE)
- yaeyamensis, Enteroplax yaeyamensis T. Habe & M. Chinen, 1974 - syn of: Enteroplax yaeyamaensis T. Habe & M. Chinen, 1974 - (STROBILOPSIDAE)
- yagan, Neolepton yagan D.G. Zelaya & C.F. Ituarte, 2004 - (NEOLEPTONIDAE)
- yagii, Crioceratites yagii Yabe & Shimizu, 1927 † - (CRIOCERATITIDAE) (FOSSIL)
- yaguajayensis, Mimiaxis yaguajayensis (C. de la Torre & P. Bartsch, 1972) - (UROCOPTIDAE)
- yaguajayensis, Torrecoptis yaguajayensis C. de la Torre & P. Bartsch, 1972 - syn of: Mimiaxis yaguajayensis (C. de la Torre & P. Bartsch, 1972) - (UROCOPTIDAE)
- yaguaronis, Diplodon yaguaronis W.B. Marshall, 1930 - syn of: Diplodon rhuacoicus (A.V.M.D. D'Orbigny, 1835) - (HYRIIDAE)
- Yagudinella, Subgenus Serripes (Yagudinella) A.I. Kafanov, 1975 (CARDIIDAE) (FOSSIL)
- yaguense, Bittium yaguense W.M. Gabb, 1873 † - (CERITHIIDAE) (FOSSIL)
- yagurai, Euhadra latispira yagurai J.T. Kuroda & T. Habe, 1949 - (BRADYBAENIDAE)
- yagurai, Megalophaedusa yagurai (J.T. Kuroda, 1936) - (CLAUSILIIDAE)
- yagurai, Crenocrassatella yagurai (J. Makiyama, 1927) - (CRASSATELLIDAE)
- yagurai, Ziba yagurai T. Kira, 1959 - syn of: Ziba interlirata (L.A. Reeve, 1844) - (MITRIDAE)
- yahagiensis, Pleuronautilus yahagiensis Ehiro, 1995 † - (TAINOCERATIDAE) (FOSSIL)
- yahatai, Euhadra sandai yahatai J.T. Kuroda & M. Azuma, 1982 - (BRADYBAENIDAE)
- yahikoensis, Aegista proba yahikoensis J.T. Kuroda, 1953 - (BRADYBAENIDAE)
- yahliensis, Serripecten yahliensis (Tenison Woods, 1865 †) - (PECTINIDAE) (FOSSIL)
- yailense, Plesiodiceras yailense Pchelintsev, 1959 † - (EPIDICERATIDAE) (FOSSIL)
- yairipokensis, Trachycardium yairipokensis Sijagurumayum, Singh & Kachhara, 2014 † - (CARDIIDAE) (FOSSIL)
- yajiangense, Stacheoceras yajiangense Sheng, 1984 † - (NEOSTACHEOCERATIDAE) (FOSSIL)
- yajiangensis, Unionelloides yajiangensis (H.X. Liu, 1984 †) - (UNIONIDAE) (FOSSIL)
- yakatagensis, Cyclocardia yakatagensis (Clark, 1932 †) - (CARDITIDAE) (FOSSIL)
- yakounensis, Anahoplites yakounensis J.J.F. Whiteaves, 1900 † - (HOPLITIDAE) (FOSSIL)
- Yakounia, Genus Yakounia Jakobs & Smith, 1996 (HILDOCERATIDAE) (FOSSIL)
- yakowlewi, Globodoma yakowlewi Mazaev, 2006 † - (GOSSELETINIDAE) (FOSSIL)
- yakowlewi, Biarmeaspira yakowlewi (Licharew, 1967 †) - (PHYMATOPLEURIDAE) (FOSSIL)
- yakowlewi, Postprolobites yakowlewi Wedekind, 1913 † - syn of: Prionoceras divisum (G.G. Münster, 1832 †) - (PRIONOCERATIDAE) (FOSSIL)
- Yakuchloritis, Genus Yakuchloritis T. Habe, 1956 (CAMAENIDAE)
- Yakuena, Genus Yakuena T. Habe, 1955 (ENIDAE)
- Yakuena, syn of: Genus Luchuena T. Habe, 1955 (ENIDAE)
- yakuensis, Microcystina yakuensis H.A. Pilsbry, 1902 - (ARIOPHANTIDAE)
- yakuensis, Discoconulus yakuensis H.A. Pilsbry, 1902 - (EUCONULIDAE)
- yakushimae, Hemizaptyx ptychocyma yakushimae (H.A. Pilsbry, 1901) - (CLAUSILIIDAE)
- yakushimae, Diplommatina yakushimae H.A. Pilsbry, 1901 - (DIPLOMMATINIDAE)
- yakushimae, Gulella iwakawa yakushimae H.A. Pilsbry, 1901 - (STREPTAXIDAE)
- yakushimae, Nototeredo yakushimae T. Habe, 1952 - syn of: Nototeredo edax (C. Hedley, 1895) - (TEREDINIDAE)
- yakushimana, Euhadra herklotsi yakushimana H.A. Pilsbry & Y. Hirase, 1903 - (BRADYBAENIDAE)
- yakushimanum, Spirostoma japonica yakushimanum H.A. Pilsbry & Y. Hirase, 1908 - (CYCLOPHORIDAE)
- yakutensis, Sirenites yakutensis (Kiparisova, 1937 †) - (TRACHYCERATIDAE) (FOSSIL)
- Yakutionautilus, Genus Yakutionautilus Popov, 1951 (TRIGONOCERATIDAE) (FOSSIL)
- Yakutoceras, Genus Yakutoceras Popov, 1970 (ORULGANITIDAE) (FOSSIL)
- Yakutoglaphyrites, Genus Yakutoglaphyrites Ruzhentzev, 1960 (ORULGANITIDAE) (FOSSIL)
- yakutorum, Tumaroceras yakutorum Ruzhentsev, 1961 † - (PARAGASTRIOCERATIDAE) (FOSSIL)
- Yakutosirenites, Genus Yakutosirenites Tozer , 1994 (TRACHYCERATIDAE) (FOSSIL)
- yalakensis, Sturia yalakensis Arthaber, 1914 † - (STURIIDAE) (FOSSIL)
- yaldwyni, Allodiscus yaldwyni B.A. Marshall & G.M. Barker, 2008 - (CHAROPIDAE)
- yaldwyni, Rhytida yaldwyni R.K. Dell, 1955 - (RHYTIDIDAE)
- yallahensis, Colobostylus yallahensis (C.B. Adams, 1851) - (POMATIIDAE)
- yallahsensis, Lucidella yallahsensis H.A. Pilsbry & A.P. Brown, 1912 - (HELICINIDAE)
- yallahsensis, Cyclochittya yallahsensis (P. Bartsch, 1942) - (NEOCYCLOTIDAE)
- yaloka, Palmadusta humphreyii yaloka W.R. Steadman & B.C. Cotton, 1943 - (CYPRAEIDAE)
- yalvacensis, Sprattia blissi yalvacensis H. Nordsieck, 2004 - (CLAUSILIIDAE)
- yama, Ammonites yama E. Forbes, 1846 † - syn of: Pachydiscus yama (E. Forbes, 1846 †) - (AMMONITIDA (unassigned)) (FOSSIL)
- yama, Pachydiscus yama (E. Forbes, 1846 †) - (DESMOCERATIDAE) (FOSSIL)
- yamadai, Cryptoplax yamadai Is. Taki, 1962 - (CRYPTOPLACIDAE)
- yamadana, Lirularia yamadana (E.A. Smith, 1875) - (TROCHIDAE)
- yamagatana, Cnesterium yamagatana S. Nomura & N. Zinbo, 1937 † - (YOLDIIDAE) (FOSSIL)
- yamaguchi, Biwamelania habei yamaguchi (J.B. Burch, 1968) - (SEMISULCOSPIRIDAE)
- yamaguchii, Haminoea yamaguchii T. Habe, 1952 - (HAMINOEIDAE)
- yamagutii, Nesopupa yamagutii J.T. Kuroda, 1941 - (VERTIGINIDAE)
- yamakawaensis, Thyasira yamakawaensis T. Habe, 1949 - (THYASIRIDAE)
- yamakawai, Acteocina yamakawai M. Yokoyama, 1926 - (ACTEOCINIDAE)
- yamakawai, Cylichna yamakawai M. Yokoyama, 1920 † - syn of: Cylichnatys angusta (A.A. Gould, 1859) - (CYLICHNIDAE) (FOSSIL)
- yamakawai, Epitonium yamakawai M. Yokoyama, 1922 - (EPITONIIDAE)
- yamakawai, Episiphon yamakawai M. Yokoyama, 1927 - (GADILINIDAE)
- yamakawai, Glycymeris yamakawai M. Yokoyama, 1922 - syn of: Glycymeris rotunda (R.W. Dunker, 1882) - (GLYCYMERIDIDAE)
- yamakawai, Laevidentalium yamakawai M. Yokoyama, 1927 † - (LAEVIDENTALIIDAE) (FOSSIL)
- yamakawai, Byssobornia yamakawai (M. Yokoyama, 1922) - (LASAEIDAE)
- yamakawai, Parvilucina yamakawai (M. Yokoyama, 1920) - (LUCINIDAE)
- yamakawai, Montacuta yamakawai M. Yokoyama, 1922 - syn of: Byssobornia yamakawai (M. Yokoyama, 1922) - (MONTACUTIDAE)
- yamakawai, Clathrofenella yamakawai (M. Yokoyama, 1924) - (SCALIOLIDAE)
- yamakawai, Acharax yamakawai M. Yokoyama, 1927 - syn of: Acharax japonica (R.W. Dunker, 1882) - (SOLEMYIDAE)
- yamakawai, Solemya yamakawai M. Yokoyama, 1927 - syn of: Acharax japonica (R.W. Dunker, 1882) - (SOLEMYIDAE)
- yamakawana, Cinctiscala yamakawana M. Yokoyama, 1922 - syn of: Epitonium yamakawai M. Yokoyama, 1922 - (EPITONIIDAE)
- yamamatoi, Neomenia yamamatoi K. Baba, 1975 - (NEOMENIIDAE)
- yamamotoaizoi, Otesiopsis yamamotoaizoi H. Minato, 1974 - (ARIOPHANTIDAE)
- yamamotoi, Hawaiarca yamamotoi (K. Sakurai & T. Habe in T. Habe, 1961) - (ARCIDAE)
- yamamotoi, Annulobalcis yamamotoi T. Habe, 1974 - (EULIMIDAE)
- yamamotoi, Pelseneeria yamamotoi (T. Habe, 1952) - (EULIMIDAE)
- yamamotoi, Cellana yamamotoi T. Kase, T. Nakano, Y. Kurihara & T. Haga, 2013 † - (NACELLIDAE) (FOSSIL)
- yamamotoi, Neomenia yamamotoi K. Baba, 1975 - syn of: Neomenia yamamatoi K. Baba, 1975 - (NEOMENIIDAE)
- yamamotoi, Fossarus yamamotoi T. Habe, 1978 - syn of: Macromphalus yamamotoi (T. Habe, 1978) - (PLANAXIDAE)
- yamamotoi, Trimusculus yamamotoi T. Habe, 1958 - (TRIMUSCULIDAE)
- yamamotoi, Macromphalus yamamotoi (T. Habe, 1978) - (VANIKORIDAE)
- yamamotoi, Psephaea kaneko yamamotoi T. Shikama, 1967 - (VOLUTIDAE)
- Yamamotolepida, Genus Yamamotolepida T. Habe, 1976 (GALEOMMATIDAE)
- yamamotonis, Paludinassiminea yamamotonis J.T. Kuroda - (ASSIMINEIDAE)
- yamamurae, Acteon yamamurae T. Habe, 1976 - (ACTEONIDAE)
- yamamurae, Mactrotoma yamamurae T. Habe & S. Kosuge, 1966 - syn of: Heterocardia gibbosula G.P. Deshayes, 1855 - (MACTRIDAE)
- yamamurae, Astralium yamamurae T. Habe & S. Kosuge, 1966 - (TURBINIDAE)
- yamamurai, Coralliophila yamamurai Y. Goto, 1989 - syn of: Hirtomurex kawamurai (T. Shikama, 1978) - (MURICIDAE)
- yamana, Graneledone yamana J. Guerrero-Kommritz, 2000 - (OCTOPODIDAE)
- yamanarii, Tateiwaia yamanarii J. Makiyama, 1959 † - syn of: Tateiwaia tateiwai (J. Makiyama, 1934 †) - (POTAMIDIDAE) (FOSSIL)
- yamanii, Sportella yamanii Abbass, 1972 † - (SPORTELLIDAE) (FOSSIL)
- yamasakii, Ciliatocardium yamasakii J. Makiyama † - syn of: Ciliatocardium evsseevi A.I. Kafanov & Savizky, 1982 † - (CARDIIDAE) (FOSSIL)
- yamasakii, Modiolus yamasakii (J. Makiyama, 1934 †) - (MYTILIDAE) (FOSSIL)
- yamashitai, Kummeloceras yamashitai E. Matsumoto, 1983 † - syn of: Kummelonautilus yamashitai (E. Matsumoto, 1983 †) - (DOMATOCERATIDAE) (FOSSIL)
- yamashitai, Kummelonautilus yamashitai (E. Matsumoto, 1983 †) - (NAUTILIDAE) (FOSSIL)
- yamasui, Cuthona yamasui I. Hamatani, 1993 - (FIONIDAE)
- yamato, Pyropelta yamato T. Sasaki, T.A. Okutani & K. Fujikura, 2003 - (PYROPELTIDAE)
- Yamatochlamys, Genus Yamatochlamys T. Habe, 1945 (HELICARIONIDAE)
- yamatoensis, Babelomurex yamatoensis S. Kosuge, 1986 - (MURICIDAE)
- yamatoensis, Alvania yamatoensis K. Hasegawa, 2014 - (RISSOIDAE)
- yamatotaiensis, Maorithyas yamatotaiensis T.A. Okutani & Izumidate, 1992 - syn of: Adontorhina cyclia S.S. Berry, 1947 - (THYASIRIDAE)
- yamauchii, Venatomya yamauchii Itoigawa 1960k † - (MYIDAE) (FOSSIL)
- yamazakii, Ancistrolepis grammatus yamazakii J.T. Kuroda, 1944 - (BUCCINIDAE)
- yamazii, Melanella yamazii (T. Habe, 1952) - (EULIMIDAE)
- yambarensis, Vaugonia yambarensis Kobayashi, 1956 † - (MYOPHORELLIDAE) (FOSSIL)
- yami, Reinia eastlakeana yami J.T. Kuroda & T. Kano, 1941 - (CLAUSILIIDAE)
- yammerana, Kimboraga yammerana G.A. Solem, 1985 - (CAMAENIDAE)
- yamneyensis, Alycaeus yamneyensis H.H. Godwin-Austen, 1914 - (CYCLOPHORIDAE)
- yamneyensis, Raphaulus yamneyensis H.H. Godwin-Austen, 1917 - (PUPINIDAE)
- yampiensis, Kimboraga yampiensis G.A. Solem, 1985 - (CAMAENIDAE)
- yanagawana, Leukoma yanagawana Nomura & Zinbo 1936 † - (VENERIDAE) (FOSSIL)
- yanagawensis, Inversiunio yanagawensis (T. Kondo, 1982) - (UNIONIDAE)
- yanagisawai, Pachythaerus yanagisawai Tashiro, 1988 † - (CRASSATELLIDAE) (FOSSIL)
- yanamensis, Thaumastus yanamensis P.M.A. Morelet, 1863 - (MEGASPIRIDAE)
- yanamii, Plicifusus yanamii M. Yokoyama, 1926 - syn of: Retifusus virens (W.H. Dall, 1877) - (BUCCINIDAE)
- yanamii, Retifusus yanamii M. Yokoyama, 1926 - syn of: Retifusus virens (W.H. Dall, 1877) - (BUCCINIDAE)
- yanamii, Tachyrhynchus yanamii (M. Yokoyama, 1926) - (TURRITELLIDAE)
- yanceyi, Megalodon yanceyi Nakazawa, 2002 † - (MEGALODONTIDAE) (FOSSIL)
- yanceyi, Clinuropsis yanceyi Garvie, 2013 † - (RAPHITOMIDAE) (FOSSIL)
- yandellana, Loxonema yandellana J.W. Hall, 1856 † - syn of: Pseudozygopleura yandellana (J.W. Hall, 1856 †) - (LOXONEMATIDAE) (FOSSIL)
- yandellana, Trochonemopsis yandellana (J.W. Hall & R.P. Whitfield, 1872 †) - (OMPHALOTROCHIDAE) (FOSSIL)
- yandellana, Palaeozygopleura yandellana J.W. Hall, 1856 † - syn of: Pseudozygopleura yandellana (J.W. Hall, 1856 †) - (PALAEOZYGOPLEURIDAE) (FOSSIL)
- yandellana, Pseudozygopleura yandellana (J.W. Hall, 1856 †) - (PSEUDOZYGOPLEURIDAE) (FOSSIL)
- yandongensis, Halobia yandongensis C. Chen, 1976 † - (HALOBIIDAE) (FOSSIL)
- yangbayensis, Amphidromus yangbayensis Thach & Huber, 2016 - (CAMAENIDAE)
- yangbiensis, Amnicola yangbiensis Pan, 1977 † - (AMNICOLIDAE) (FOSSIL)
- yangcaogouensis, Liaoningia yangcaogouensis Mi, Zhang & W.K.C. Sun 1993 † - (LIAONINGIIDAE) (FOSSIL)
- Yangella, Genus Yangella Liu & Gu, 1989 (TRIGONIIDA (UNASSIGNED)) (FOSSIL)
- yanghaoi, Synprosphyma yanghaoi J. Grego & M. Szekeres, 2011 - (CLAUSILIIDAE)
- yanghaoi, Gudeodiscus yanghaoi B. Páll-Gergely & A. Hunyadi, 2013 - (PLECTOPYLIDAE)
- yangi, Vexillum yangi S.I. Huang, 2017 - (COSTELLARIIDAE)
- yangi, Epitonium yangi L.G. Brown, 2010 - (EPITONIIDAE)
- yangi, Nicimitoceras yangi (W.K.C. Sun & S. Shen, 1965 †) - (GATTENDORFIIDAE) (FOSSIL)
- yangi, Imitoceras yangi W.K.C. Sun & S. Shen, 1965 † - syn of: Nicimitoceras yangi (W.K.C. Sun & S. Shen, 1965 †) - (PRIONOCERATIDAE) (FOSSIL)
- yangi, Bigalea yangi Pojeta & Runnegar, 1976 † - (PSEUDOBIGALEAIDAE) (FOSSIL)
- yangi, Trivirostra yangi D. Fehse & J. Grego, 2006 - (TRIVIIDAE)
- Yangites, Genus Yangites Balini & Zou, 2015 (CERATITIDAE) (FOSSIL)
- yangjiaheensis, Aldanella yangjiaheensis Shaler & Foerste, 1888 † - syn of: Aldanella attleborensis (Shaler & Foerste, 1888 †) - (ALDANELLIDAE) (FOSSIL)
- yangouensis, Jiangxispira yangouensis Pan & al., 2003 † - (STREPTACIDIDAE) (FOSSIL)
- yangtseensis, Nucula yangtseensis Frech, 1911 † - syn of: Nuculopsis yangtzeensis (Frech, 1911 †) - (NUCULIDAE) (FOSSIL)
- yangtsunghaiensis, Tchangmargarya yangtsunghaiensis (S. Tchang & C.Y. Tsi, 1949) - (VIVIPARIDAE)
- Yangtzeconus, Genus Yangtzeconus Yό , 1979 (POLLICINIDAE) (FOSSIL)
- Yangtzedonta, Genus Yangtzedonta Yu, 1985 (BIVALVIA INCERTAE SEDIS) (FOSSIL)
- yangtzeense, Retroclitendoceras yangtzeense F.S. Xu, 1981 † - (PROTEROCAMEROCERATIDAE) (FOSSIL)
- yangtzeensis, Anadenus yangtzeensis A. Wiktor, C. De-niu & W. Ming, 2000 - (ANADENIDAE)
- yangtzeensis, Nuculopsis yangtzeensis (Frech, 1911 †) - (NUCULIDAE) (FOSSIL)
- Yangtzemerisma, Genus Yangtzemerisma Yu, 1984 (MOLLUSCA INCERTAE SEDIS) (FOSSIL)
- Yangtzespira, syn of: Genus Oelandiella Vostokova , 1962 (HELCIONELLIDAE) (FOSSIL)
- yangziensis, Vishnuites yangziensis F.S. Xu, 1988 † - syn of: Vishnuites pralambha Diener, 1897 † - (OPHICERATIDAE) (FOSSIL)
- Yanheceras, Genus Yanheceras Chen in Chen Tsou, Chen & Qi, 1979 (YANHECERIDA (UNASSIGNED)) (FOSSIL)
- YANHECERIDA (UNASSIGNED) - Family (CEPHALOPODA-AMMONOIDEA [Subclass]-YANHECERIDA [Order]) (FOSSIL)
- yani, Stilpnodiscus yani W.L. Wu, 2001 - (BRADYBAENIDAE)
- yani, Asperitas stuartiae yani B. Dharma, 1999 - (DYAKIIDAE)
- yani, Volvarina yani J. Espinosa & J.A. Ortea, 2012 - (MARGINELLIDAE)
- yaninae, Adacna yaninae Büyükmeriç & Wesselingh, 2016 † - (CARDIIDAE) (FOSSIL)
- Yaninella, Genus Yaninella M.R. Cooper, 2015 (PTEROTRIGONIIDAE) (FOSSIL)
- yanjiaensis, Koninckites yanjiaensis F.S. Xu, 1988 † - syn of: Huananoceras pseudoopalinum (Frech, 1895 †) - (BEYRICHITIDAE) (FOSSIL)
- yanjiaensis, Kymatites yanjiaensis F.S. Xu, 1988 † - (GYRONITIDAE) (FOSSIL)
- yanjiaensis, Hubeitoceras yanjiaensis (F.S. Xu, 1988 †) - (PROPTYCHITIDAE) (FOSSIL)
- yanjiaheensis, Aldanella yanjiaheensis C. Chen, 1984 † - syn of: Aldanella attleborensis (Shaler & Foerste, 1888 †) - (ALDANELLIDAE) (FOSSIL)
- yanjiaheensis, Bemella yanjiaheensis C. Chen, 1984 † - (HELCIONELLIDAE) (FOSSIL)
- yanjiahensis, Aldanella yanjiahensis Shaler & Foerste, 1888 † - syn of: Aldanella attleborensis (Shaler & Foerste, 1888 †) - (ALDANELLIDAE) (FOSSIL)
- yanjiensis, Palaeoneilo yanjiensis H. Guo, 1985 † - (MALLETIIDAE) (FOSSIL)
- yanjiensis, Nippononaia yanjiensis Gu & Yu, 1976 † - (NIPPONONAIIDAE) (FOSSIL)
- yankovi, Balkanica yankovi D.G. Georgiev, 2011 - (HYDROBIIDAE)
- Yannanoceras, Genus Yannanoceras (CEPHALOPODA (UNASSIGNED)) (FOSSIL)
- yanoi, Tyrannophaedusa nankaidoensis yanoi H. Minato, 1978 - (CLAUSILIIDAE)
- yanoshigehumii, Chamalycaeus yanoshigehumii H. Minato, 1987 - (CYCLOPHORIDAE)
- yanoshokoae, Alycaeus yanoshokoae Yano & Matsuda, 2016 - (CYCLOPHORIDAE)
- yanseni, Pincerna yanseni B. Páll-Gergely, 2017 - (CYCLOPHORIDAE)
- yanseni, Arinia yanseni Nurinsiyah & Hausdorf, 2017 - (DIPLOMMATINIDAE)
- yanshanense, Yongpingoceras yanshanense X.T. Ma & Li, 1998 † - syn of: Nodogastrioceras discum X.T. Ma & Li, 1998 † - (PARAGASTRIOCERATIDAE) (FOSSIL)
- yanshini, Kazakhoceras yanshini Ruzhentsev, 1947 † - (BERKHOCERATIDAE) (FOSSIL)
- yantaiensis, Metodontia yantaiensis (J.C.H. Crosse & E.O. Debeaux, 1863) - (BRADYBAENIDAE)
- yantaiensis, Fragilia yantaiensis J.C.H. Crosse & G.P. Deshayes, 1863 - syn of: Heteromacoma irus (S.C.T. Hanley, 1845) - (TELLINIDAE)
- yanuyanuensis, Conus yanuyanuensis Ladd, 1945 † - (CONIDAE) (FOSSIL)
- yaowalakae, Tapashanites yaowalakae Ishibashi & al., 1994 † - (TAPASHANITIDAE) (FOSSIL)
- yapacanensis, Drymaeus yapacanensis A.S.H. Breure & A. Eskens, 1981 - (BULIMULIDAE)
- yapigium, Cochlostoma westerlundi yapigium (C.A. Westerlund, 1885) - (COCHLOSTOMATIDAE)
- yappalana, Cupedora yappalana G.A. Solem, 1992 - (CAMAENIDAE)
- yaquense, Parachondria yaquense P. Bartsch, 1946 - (POMATIIDAE)
- yaquensis, Arca yaquensis C.J. Maury, 1917 † - (ARCIDAE) (FOSSIL)
- yaquensis, Arcinella yaquensis (C.J. Maury, 1917 †) - (CHAMIDAE) (FOSSIL)
- yaquensis, Conus yaquensis W.M. Gabb, 1873 † - (CONIDAE) (FOSSIL)
- yaquensis, Parvilucina yaquensis (W.M. Gabb, 1873 †) - (LUCINIDAE) (FOSSIL)
- yaquensis, Phacoides yaquensis C.J. Maury, 1917 † - (LUCINIDAE) (FOSSIL)
- yaquensis, Siratus yaquensis C.J. Maury, 1917 † - (MURICIDAE) (FOSSIL)
- yaquensis, Turbonilla yaquensis C.J. Maury, 1917 † - (PYRAMIDELLIDAE) (FOSSIL)
- yaquensis, Retusa yaquensis C.J. Maury, 1917 † - (RETUSIDAE) (FOSSIL)
- yaquensis, Psammacoma yaquensis C.J. Maury, 1917 † - syn of: Psammacoma olivella W.H. Dall, 1900 † - (TELLINIDAE) (FOSSIL)
- yaquensis, Sonoraloa remondii yaquensis (H.A. Pilsbry, 1953) - (UROCOPTIDAE)
- yaquensis berryi, Arca yaquensis berryi W.P. Woodring, 1925 - (ARCIDAE)
- Yaquicoccus, syn of: Genus Pyrgulopsis R.E. Call & H.A. Pilsbry, 1886 (HYDROBIIDAE)
- Yaquinabyssia, Genus Yaquinabyssia G. Haszprunar, 1988 (PSEUDOCOCCULINIDAE)
- yaquinae, Muusoctopus yaquinae (N.A. Voss & W.G. Pearcy, 1990) - (ENTEROCTOPODIDAE)
- yaquinae, Leionucula yaquinae Bernard, 1983 - syn of: Ennucula cardara (W.H. Dall, 1916) - (NUCULIDAE)
- yaquinae, Nucula yaquinae F.R. Bernard, 1983 - syn of: Ennucula cardara (W.H. Dall, 1916) - (NUCULIDAE)
- yaquinae, Benthoctopus yaquinae N.A. Voss & W.G. Pearcy, 1990 - syn of: Muusoctopus yaquinae (N.A. Voss & W.G. Pearcy, 1990) - (OCTOPODIDAE)
- yara, Axelella yara B.M. Landau & R.E. Petit, 2007 † - (CANCELLARIIDAE) (FOSSIL)
- yarkandense, Pisidium yarkandense B. Prashad, 1933 - (SPHAERIIDAE)
- yaroni, Anatoma yaroni D.G. Herbert, 1986 - (ANATOMIDAE)
- yaroni, Pseudotorinia yaroni R. Bieler, 1993 - (ARCHITECTONICIDAE)
- yaroni, Chama yaroni A. Delsaerdt, 1986 - (CHAMIDAE)
- yaroni, Diodora yaroni J.M.J. Christiaens, 1987 - (FISSURELLIDAE)
- yaroni, Mirapecten yaroni H.H. Dijkstra & J. Knudsen, 1998 - (PECTINIDAE)
- yaroni isaaci, Diodora yaroni isaaci J.M.J. Christiaens, 1987 - (FISSURELLIDAE)
- Yaronia, Genus Yaronia H.K. Mienis, 2011 (TURBINIDAE)
- Yaroslawiella, Genus Yaroslawiella T.Y. Sitnikova, 2001 (LITHOGLYPHIDAE)
- yarramundi, Colpospira yarramundi (T.A. Garrard, 1972) - (TURRITELLIDAE)
- yarramundi, Acutospira yarramundi T.A. Garrard, 1972 - syn of: Colpospira yarramundi (T.A. Garrard, 1972) - (TURRITELLIDAE)
- yartanicus, Oxychilus yartanicus C.R. Altaba, 2007 - (OXYCHILIDAE)
- yasawaensis, Cystiscus yasawaensis A. Wakefield & T. McCleery, 2006 - (CYSTISCIDAE)
- yashima, Tomura yashima H. Fukuda & H. Yamashita, 1997 - (CORNIROSTRIDAE)
- yasila, Fusiturricula yasila A.A. Olsson, 1930 † - (DRILLIIDAE) (FOSSIL)
- yasila, Mitra yasila A.A. Olsson, 1930 † - (MITRIDAE) (FOSSIL)
- Yasila, Genus Yasila Olsson, 1930 (MURICIDAE) (FOSSIL)
- yasila, Pitar yasila A.A. Olsson, 1930 † - (VENERIDAE) (FOSSIL)
- yasilum, Dentalium yasilum A.A. Olsson, 1930 † - (DENTALIIDAE) (FOSSIL)
- yasoda, Procladiscites yasoda (Diener, 1895 †) - (CLADISCITIDAE) (FOSSIL)
- yastchanensis, Chlamys yastchanensis Milova, 1985 † - (PECTINIDAE) (FOSSIL)
- yasukawensis, Hikidea yasukawensis (A. Kaim & al., 2009 †) - (COLLONIIDAE) (FOSSIL)
- yasukawensis, Cantrainea yasukawensis A. Kaim & al., 2009 † - syn of: Hikidea yasukawensis (A. Kaim & al., 2009 †) - (COLLONIIDAE) (FOSSIL)
- yatalaensis, Ventopelita yatalaensis (J.C. Cox, 1873) - (CAMAENIDAE)
- yatalensis, Cadulus yatalensis N.H. Ludbrook, 1956 † - (GADILIDAE) (FOSSIL)
- yateensis, Dischides yateensis V. Scarabino, 1995 - (GADILIDAE)
- yatei, Bassina yatei (J.E. Gray, 1835) - (VENERIDAE)
- yatei, Venus yatei J.E. Gray, 1835 - syn of: Bassina yatei (J.E. Gray, 1835) - (VENERIDAE)
- yatei, Circomphalus yatei (J.E. Gray, 1835) - syn of: Bassina yatei (J.E. Gray, 1835) - (VENERIDAE)
- yateracense, Tudora yateracense L. Pfeiffer, 1865 - syn of: Annularisca yaterasensis (L. Pfeiffer, 1865) - (POMATIIDAE)
- yaterasensis, Annularisca yaterasensis (L. Pfeiffer, 1865) - (POMATIIDAE)
- yaterasensis, Ramsdenia nobilitata yaterasensis (C. de la Torre & P. Bartsch, 1941) - (POMATIIDAE)
- yateresense, Macroceramus yateresense M.I. Sánchez Roig - (UROCOPTIDAE)
- yatesi, Labyrinthus yatesi (L. Pfeiffer, 1855) - (CAMAENIDAE)
- yatesi, Miodontiscus yatesi R. Arnold, 1907 - syn of: Miodontiscus prolongatus (Carpenter, 1864) - (CARDITIDAE)
- yatesi, Venericardia yatesi R. Arnold, 1907 - syn of: Miodontiscus prolongatus (Carpenter, 1864) - (CARDITIDAE)
- yatesi, Hungarites yatesi A. Hyatt & Smith, 1905 † - syn of: Subhungarites yatesi (A. Hyatt & Smith, 1905 †) - (CERATITIDAE) (FOSSIL)
- yatesi, Subhungarites yatesi (A. Hyatt & Smith, 1905 †) - (LONGOBARDITIDAE) (FOSSIL)
- yatesi, Monstrotyphis yatesi (J.C.H. Crosse & P.H. Fischer, 1865) - (MURICIDAE)
- yatesi, Kaloplocamus yatesi (G.F. Angas, 1864) - (POLYCERIDAE)
- yatesi, Limacia yatesi G.F. Angas, 1864 - syn of: Kaloplocamus yatesi (G.F. Angas, 1864) - (POLYCERIDAE)
- yatesi, Xianfengella yatesi Parkhaev, 2001 † - (RUGAECONIDAE) (FOSSIL)
- yatesi, Subulina yatesi (L. Pfeiffer, 1855) - (SUBULINIDAE)
- yatesi, Clanculus yatesi J.C.H. Crosse, 1863 - syn of: Clanculus philippii (Koch in R.A. Philippi, 1843) - (TROCHIDAE)
- yatesi, Gymnotropites yatesi A. Hyatt & Smith 1905 † - (TROPITIDAE) (FOSSIL)
- yatesii, Pomacea urceus yatesii (L.A. Reeve, 1856) - (AMPULLARIIDAE)
- yatesii, Hemitoma yatesii W.H. Dall, 1901 - syn of: Scelidotoma bella (W.M. Gabb, 1865) - (FISSURELLIDAE)
- yatesii, Ammonitella yatesii J.G. Cooper, 1869 - (MEGOMPHICIDAE)
- yatesii, Sultana yatesii (L. Pfeiffer, 1855) - (ORTHALICIDAE)
- yatesii galactostomus, Sultana yatesii galactostomus (C.M.F. Ancey, 1890) - (ORTHALICIDAE)
- yatesii vicarius, Sultana yatesii vicarius H.C. Fulton, 1896 - (ORTHALICIDAE)
- yatsui, Herviella yatsui (K. Baba, 1930) - (GLAUCIDAE)
- yatsui, Lyrodus yatsui C.E. von Moll, 1929 - syn of: Lyrodus pedicellatus (J.L.A. Quatrefages, 1849) - (TEREDINIDAE)
- yaucoi, Licina decussata yaucoi H.B. Baker, 1962 - (POMATIIDAE)
- yauyeejiae, Amphidromus yauyeejiae Thach & Abbas, 2017 - (CAMAENIDAE)
- yavapai, Oreohelix yavapai H.A. Pilsbry, 1905 - (OREOHELICIDAE)
- yavapai cummingsi, Oreohelix yavapai cummingsi H.A. Pilsbry, 1934 - (OREOHELICIDAE)
- yavapai extremitatis, Oreohelix yavapai extremitatis H.A. Pilsbry & J.H. Ferriss, 1911 - (OREOHELICIDAE)
- yavapai fortis, Oreohelix yavapai fortis T.D.A. Cockerell, 1927 - (OREOHELICIDAE)
- yavapai mariae, Oreohelix yavapai mariae P. Bartsch, 1916 - (OREOHELICIDAE)
- yavapai profundorum, Oreohelix yavapai profundorum H.A. Pilsbry & J.H. Ferriss, 1911 - (OREOHELICIDAE)
- yawii, Paryphantopsis yawii J. Slapcinsky, 2005 - (CHAROPIDAE)
- yayaeli, Volvarina yayaeli J. Espinosa, J.A. Ortea & L. Moro, 2009 - (MARGINELLIDAE)
- yayanae, Mitra yayanae Y.F. Huang, 2011 - (MITRIDAE)
- Yayoiacmaea, syn of: Genus Yayoiacmea T. Sasaki & T.A. Okutani, 1993 (LOTTIIDAE)
- Yayoiacmea, Genus Yayoiacmea T. Sasaki & T.A. Okutani, 1993 (LOTTIIDAE)
- ybessa, Pleurotomella ybessa R.M.A. Figueira & R.S. Absalão, 2012 - (RAPHITOMIDAE)
- ycaunica, Trochoidea ycaunica J.F. Mabille, 1881 - syn of: Amandana geyeri (L. Soós, 1926) - (HYGROMIIDAE)
- Yeddoconus, syn of: Genus Endemoconus T. Iredale, 1931 (CONIDAE)
- yeddoensis, Turris yeddoensis (F.P. Jousseaume, 1883) - (TURRIDAE)
- yeehaw, Sinistrofulgur yeehaw E.J. Petuch, 1994 † - (BUSYCONIDAE) (FOSSIL)
- yeharai, Mytiloides stantoni yeharai T. Nagao & E. Matsumoto, 1939 † - (INOCERAMIDAE) (FOSSIL)
- yeharai, Oxytoma yeharai Kobayashi & M. Ichikawa † - syn of: Oxytoma mojsisovicsi Teller, 1886 † - (OXYTOMIDAE) (FOSSIL)
- yeharai, Rutitrigonia yeharai T. Kobayashi, 1957 † - (RUTITRIGONIIDAE) (FOSSIL)
- yeharai, Arctoprionites yeharai (Bando, 1964 †) - (SIBIRITIDAE) (FOSSIL)
- Yeharella, Genus Yeharella Kobayashi & Amano, 1955 (STEINMANELLIDAE) (FOSSIL)
- yehiai, Sassia yehiai Abbass, 1967 † - (RANELLIDAE) (FOSSIL)
- Yehlioceras, Genus Yehlioceras Obata, 1940 (ENDOCERIDA (UNASSIGNED)) (FOSSIL)
- yelensis, Paryphantopsis yelensis J. Slapcinsky, 2005 - (CHAROPIDAE)
- yellowstonensis, Myophorella yellowstonensis Imlay, 1964 † - (MYOPHORELLIDAE) (FOSSIL)
- yellvillense, Endoceras yellvillense Ulrich & al., 1944 † - (ENDOCERATIDAE) (FOSSIL)
- yellvillense, Mitorthoceras yellvillense W.J. Gordon, 1964 † - (PSEUDORTHOCERATIDAE) (FOSSIL)
- yellvillense, Centrotarphyceras yellvillense Ulrich & al., 1942 † - (TARPHYCERATIDAE) (FOSSIL)
- yemanjae, Conus yemanjae J.J. Van Mol, B. Tursch & M. Kempf, 1967 - syn of: Artemidiconus selenae (G.A. de Mol, B. Tursch & M. Kempf, 1967) - (CONIDAE)
- yemayae, Intelcystiscus yemayae J. Espinosa & J.A. Ortea, 2003 - (CYSTISCIDAE)
- yemayaensis, Pygmaepterys yemayaensis Espinosa & Ortea, 2016 - (MURICIDAE)
- yemenensis, Phasmoconus yemenensis (I.P. Bondarev, 1997) - (CONIDAE)
- yemenensis, Ischnochiton yemenensis R.A. Van Belle & W. Wranik, 1991 - (ISCHNOCHITONIDAE)
- yemenensis, Megaxinus yemenensis E.A. Glover & D.W. Taylor, 1997 - (LUCINIDAE)
- yemenensis, Favartia yemenensis (R. Houart & W. Wranik, 1989) - (MURICIDAE)
- yemenensis, Austrodaphnella yemenensis A. Bonfitto, B. Sabelli & M. Morassi, 2001 - (RAPHITOMIDAE)
- yemenensis, Tellina yemenensis J.C. Melvill, 1898 - (TELLINIDAE)
- yemenensis, Brachypodella prevali yemenensis C. de la Torre & P. Bartsch, 1972 - (UROCOPTIDAE)
- yemensis, Tellina yemensis J.C. Melvill, 1888 - syn of: Tellina yemenensis J.C. Melvill, 1898 - (TELLINIDAE)
- yenanensis, Hexaplex iravadicus yenanensis E.W. Vredenburg, 1921 - (MURICIDAE)
- yenanensis, Hemipleurotoma yenanensis Noetling, 1895 † - (TURRIDAE) (FOSSIL)
- yenchuanensis, Shaanxiconcha yenchuanensis (Chow, 1953 †) - (SHAANXICONCHIDAE) (FOSSIL)
- yendoi, Amphithalamus yendoi M. Yokoyama, 1927 - syn of: Iravadia yendoi (M. Yokoyama, 1927) - (ANABATHRIDAE)
- yendoi, Iravadia yendoi (M. Yokoyama, 1927) - (IRAVADIIDAE)
- yendoi, Pseudonoba yendoi M. Yokoyama, 1927 - syn of: Iravadia yendoi (M. Yokoyama, 1927) - (IRAVADIIDAE)
- yendoi, Octopus yendoi (M. Sasaki, 1920) - (OCTOPODIDAE)
- yendoi, Rissoina yendoi M. Yokoyama, 1927 - syn of: Iravadia yendoi (M. Yokoyama, 1927) - (RISSOINIDAE)
- yeni, Stilpnodiscus yeni W.L. Wu, 2001 - syn of: Stilpnodiscus yani W.L. Wu, 2001 - (BRADYBAENIDAE)
- yeni, Filopaludina yeni Z.X. Qian, Y. Fang & J. He, 2014 - (VIVIPARIDAE)
- yenlinhae, Amphidromus yenlinhae Thach & F. Huber, 2017 - (CAMAENIDAE)
- yentaiensis, Lophospira yentaiensis Endo, 1932 † - syn of: Lophospira perangulata (J.W. Hall, 1847 †) - (LOPHOSPIRIDAE) (FOSSIL)
- yeovilense, Pleuroceras yeovilense Howarth, 1958 † - (AMALTHEIDAE) (FOSSIL)
- yeovilensis, Dumortieria yeovilensis Buckman † - (HILDOCERATIDAE) (FOSSIL)
- yeovilensis, Oxycerites yeovilensis Rollier † - (OPPELIIDAE) (FOSSIL)
- yeppoonensis, Thersites yeppoonensis R.H. Beddome, 1897 - (CAMAENIDAE)
- yerburyi, Cerithium yerburyi E.A. Smith, 1891 - syn of: Cerithium scabridum R.A. Philippi, 1848 - (CERITHIIDAE)
- yerburyi, Ischnochiton yerburyi (E.A. Smith, 1891) - (ISCHNOCHITONIDAE)
- yerburyi, Dolomena plicata yerburyi (E.A. Smith, 1891) - (STROMBIDAE)
- yerburyi, Aphrodora yerburyi (E.A. Smith, 1891) - (VENERIDAE)
- yerburyi, Pitar yerburyi E.A. Smith, 1891 - syn of: Aphrodora yerburyi (E.A. Smith, 1891) - (VENERIDAE)
- yerburyi djiboutiensis, Cerithium yerburyi djiboutiensis H. Fischer & L. Vignal in H. Fischer, 1901 - syn of: Cerithium scabridum R.A. Philippi, 1848 - (CERITHIIDAE)
- yerelinana, Lacustrelix yerelinana G.A. Solem, 1992 - (CAMAENIDAE)
- yersini, Pyrgulina yersini E. Saurin, 1959 - (PYRAMIDELLIDAE)
- yeruni, Idyla castalia yeruni (E. Gittenberger, 2002) - (CLAUSILIIDAE)
- yesimae, Ficus yesimae B.M. Landau, F. Da Silva & S.M. Heitz, 2016 † - (FICIDAE) (FOSSIL)
- yessabahensis, Coenocharopa yessabahensis J. Stanisic, 1990 - (CHAROPIDAE)
- yessoensiis, Zonitoides yessoensiis O.W.H. Reinhardt, 1877 - (GASTRODONTIDAE)
- yessoensis, Plicifusus yessoensis (L. von Schrenck, 1863) - (BUCCINIDAE)
- yessoensis, Eucrassatella yessoensis (H. Minato & Kumano, 1950 †) - (CRASSATELLIDAE) (FOSSIL)
- yessoensis, Glycymeris yessoensis G.B. III Sowerby, 1886 - (GLYCYMERIDIDAE)
- yessoensis, Mizuhopecten yessoensis (Jay, 1857) - (PECTINIDAE)
- yessoensis, Antiplanes yessoensis W.H. Dall, 1925 - syn of: Antiplanes sanctiioannis (E.A. Smith, 1875) - (PSEUDOMELATOMIDAE)
- yessoensis yokoyamae, Mizuhopecten yessoensis yokoyamae (O. Masuda, 1962 †) - (PECTINIDAE) (FOSSIL)
- yessonensis, Amamibalcis yessonensis A. Rybakov & Y.M. Yakovlev, 1993 - (EULIMIDAE)
- Yetus, syn of: Genus Cymbium P.F. Rφding, 1798 (VOLUTIDAE)
- yezoense, Kummeloceras yezoense E. Matsumoto, 1983 † - syn of: Kummelonautilus yezoensis (E. Matsumoto, 1983 †) - (DOMATOCERATIDAE) (FOSSIL)
- yezoensis, Kummelonautilus yezoensis (E. Matsumoto, 1983 †) - (NAUTILIDAE) (FOSSIL)
- Yezoites, Genus Yezoites Schlόter, 1871 (SCAPHITIDAE) (FOSSIL)
- Ygernaropa, Genus Ygernaropa Stanisic, 2010 (CHAROPIDAE)
- yichangense, Chihlioceras yichangense F.S. Xu, 1981 † - (CHIHLIOCERATIDAE) (FOSSIL)
- yichangensis, Truncatoconus yichangensis Yü, 1979 † - (HELCIONELLIDAE) (FOSSIL)
- Yichangoceras, Genus Yichangoceras Chen, 1981 (CEPHALOPODA (UNASSIGNED)) (FOSSIL)
- yidii, Gibberula yidii T. Cossignani, 2006 - (CYSTISCIDAE)
- yiizukai, Securella yiizukai K. Kanehara, 1937 † - syn of: Protocallithaca adamsi (L.A. Reeve, 1863) - (VENERIDAE) (FOSSIL)
- yildirimi, Bithynia yildirimi P. Glöer & D.G. Georgiev, 2012 - (BITHYNIIDAE)
- yildirimi, Pseudobithynia yildirimi D.A. Odabasi, Ü. Kebapçi & M. Akbulut, 2013 - (BITHYNIIDAE)
- yildirimi, Borlumastus yildirimi (H. Schütt, 1995) - (ENIDAE)
- yimgantauensis, Joleaudella yimgantauensis (Yü, 1961 †) - (BELLEROPHONTIDAE) (FOSSIL)
- yimgantauensis, Tropidodiscus yimgantauensis Yü, 1961 † - syn of: Joleaudella yimgantauensis (Yü, 1961 †) - (TROPIDODISCIDAE) (FOSSIL)
- yinganensis, Naticopsis yinganensis Qiao, 1983 † - (DELPHINULOPSIDAE) (FOSSIL)
- Yingicus, Genus Yingicus (ARCHAEOGASTROPODA (UNASSIGNED)) (FOSSIL)
- yini, Pernopecten yini Newell & Boyd, 1995 † - (PERNOPECTINIDAE) (FOSSIL)
- Yinoceras, Genus Yinoceras Zhao , 1954 (PSEUDOHALORITIDAE) (FOSSIL)
- yizhangensis, Pseudomytiloides yizhangensis Chen 1988 † - (INOCERAMIDAE) (FOSSIL)
- yizhangensis, Hunanonectes yizhangensis Y. Fang, 1978 † - syn of: Hunanonectes sanduensis Y. Fang, 1978 † - (PECTINIDAE) (FOSSIL)
- yleobia, Helix yleobia J.R. Bourguignat, 1883 - syn of: Helix lucorum C. Linnaeus, 1758 - (HELICIDAE)
- Ylistrum, Genus Ylistrum Mynhardt & Alejandrino, 2014 (PECTINIDAE)
- ylora, Andraea ylora J.R. Bourguignat, 1877 - syn of: Andraea dubia J.P.R. Draparnaud, 1805 - (CLAUSILIIDAE)
- ylva, Discodoris ylva Er. Marcus, 1965 - (DISCODORIDIDAE)
- yneziana, Vertipecten yneziana (R. Arnold, 1907 †) - (PECTINIDAE) (FOSSIL)
- yo, Aulacostephanus yo (A.V.M.D. D'Orbigny, 1845 †) - (AULACOSTEPHANIDAE) (FOSSIL)
- Yochelcionella, Genus Yochelcionella Runnegar & Pojeta, Jr., 1974 (YOCHELCIONELLIDAE) (FOSSIL)
- YOCHELCIONELLIDAE Runnegar & Jell, 1976 - Family (HELCIONELLOIDA-ARCHAEOBRANCHIA [Subclass]-HELCIONELLIFORMES [Order]-YOCHELCIONELLOIDEA [Superfamily]) (FOSSIL)
- Yochelsonatia, Genus Yochelsonatia Mawson & al., 2002 (PSEUDOPHORIDAE) (FOSSIL)
- Yochelsonella, Genus Yochelsonella Flower , 1968 (HYPSELOCONIDAE) (FOSSIL)
- Yochelsonellis, Genus Yochelsonellis Hornύ , 1966 (CYRTOLITIDAE) (FOSSIL)
- Yochelsonellisa, Genus Yochelsonellisa Waterhouse & Chen, 2006 (BELLEROPHONTIDAE) (FOSSIL)
- yochelsoni, Soleachiton yochelsoni Hoare & Smith, 1984 † - (ACUTICHITONIDAE) (FOSSIL)
- yochelsoni, Bellerophon yochelsoni Pan & Erwin, 2002 † - (BELLEROPHONTIDAE) (FOSSIL)
- yochelsoni, Stenothecoides yochelsoni Yu, 1996 † - (CAMBRIDIIDAE) (FOSSIL)
- yochelsoni, Glyptotomaria yochelsoni Knight 1945 † - (GOSSELETINIDAE) (FOSSIL)
- yochelsoni, Nordospira yochelsoni Sabattini, 1995 † - (GOSSELETINIDAE) (FOSSIL)
- yochelsoni, Dictyotomaria yochelsoni Thein & Nitecki, 1974 † - (GOSSELETINIDAE) (FOSSIL)
- yochelsoni, Retispira yochelsoni Jeffery & al., 1994 † - (KNIGHTITIDAE) (FOSSIL)
- yochelsoni, Asgardaspira yochelsoni (Rohr, 1994 †) - (OPHILETIDAE) (FOSSIL)
- yochelsoni, Pavlodiscus yochelsoni Fryda, 1998 † - (PAVLODISCIDAE) (FOSSIL)
- yochelsoni, Platyceras yochelsoni Kulas & Batten, 1997 † - (PLATYCERATIDAE) (FOSSIL)
- yochelsoni, Moorefieldoceras yochelsoni Niko & Mapes, 2015 † - (PSEUDORTHOCERATIDAE) (FOSSIL)
- yochelsoni, Umbospira yochelsoni Peel, 1977 † - (SINUOPEIDAE) (FOSSIL)
- Yochelsonia, syn of: Genus Yochelsonellis Hornύ , 1966 (CYRTOLITIDAE) (FOSSIL)
- Yochelsoniella, Genus Yochelsoniella Rohr & Huddleston, 1982 (HELICOTOMIDAE) (FOSSIL)
- YOCHELSONIIDAE Hornύ , 1962 - Family (GASTROPODA-AMPHIGASTROPODA [Subclass]-BELLEROPHONTIDA [Order]-BELLEROPHONTOIDEA [Superfamily]) (FOSSIL)
- Yochelsonistylus, Genus Yochelsonistylus Nόtzel & Nakazawa, 2012 (ORTHONEMATIDAE) (FOSSIL)
- Yochelsonospira, Genus Yochelsonospira Thein & Nitecki, 1974 (LOPHOSPIRIDAE) (FOSSIL)
- Yochleson, syn of: Subgenus Platyacra (Asperilla) Koken, 1896 (CIRRIDAE) (FOSSIL)
- Yochleson, syn of: Genus Tectus P.D. Montfort, 1810 (TEGULIDAE)
- yociusi, Triphora yociusi E. Rolán & Y.C. Lee, 2008 - (TRIPHORIDAE)
- yod, Vitreolina yod (P.P. Carpenter, 1857) - (EULIMIDAE)
- yodai, Girtyspira yodai Erwin, 1988 † - (MEEKOSPIRIDAE) (FOSSIL)
- yoga, Platycuccoceras yoga (Diener, 1907 †) - (BALATONITIDAE) (FOSSIL)
- yoguii, Schwartziella yoguii E. Rolán & R. Fernández-Garcés, 2010 - (ZEBINIDAE)
- yohi, Nicomedites yohi Hsu, 1937 † - (BEYRICHITIDAE) (FOSSIL)
- yoka, Guildfordia yoka F.P. Jousseaume, 1888 - (TURBINIDAE)
- yoka delicata, Guildfordia yoka delicata T. Habe & T.A. Okutani, 1983 - (TURBINIDAE)
- yokohamaensis, Raeta yokohamaensis H.A. Pilsbry, 1895 - syn of: Raeta pulchella (A. Adams & L.A. Reeve, 1850) - (MACTRIDAE)
- yokohamanensis, Cyrena yokohamanensis Sowerby, 1878 - syn of: Corbicula japonica T. Prime, 1864 - (CYRENIDAE)
- yokohamense, Dentalium yokohamense R.B. Watson, 1879 - syn of: Dentalium octangulatum E. Donovan, 1804 - (DENTALIIDAE)
- yokohamensis, Clausilia yokohamensis J.C.H. Crosse, 1876 - (CLAUSILIIDAE)
- yokohamensis, Raeta yokohamensis H.A. Pilsbry, 1895 † - (MACTRIDAE) (FOSSIL)
- yokojima, Thylacodes yokojima (T. Shikama, 1977) - (VERMETIDAE)
- yokomaruae, Buccinum yokomaruae H. Yamashita & T. Habe, 1965 - (BUCCINIDAE)
- yokoskensis, Leiostraca yokoskensis M. Yokoyama, 1920 † - syn of: Balcis yokosukensis (M. Yokoyama, 1920 †) - (EULIMIDAE) (FOSSIL)
- yokosukense, Cerithium yokosukense K. Oyama, 1954 - (CERITHIIDAE)
- yokosukensis, Balcis yokosukensis (M. Yokoyama, 1920 †) - (EULIMIDAE) (FOSSIL)
- yokotai, Nanaimoteuthis yokotai Tanabe, 2008 † - (VAMPYROMORPHA (UNASSIGNED)) (FOSSIL)
- Yokoyamaceras, Genus Yokoyamaceras (AMMONOIDEA (UNASSIGNED)) (FOSSIL)
- yokoyamae, Mizuhopecten yessoensis yokoyamae (O. Masuda, 1962 †) - (PECTINIDAE) (FOSSIL)
- yokoyamai, Amathina yokoyamai K. Oyama, 1954 - (AMATHINIDAE)
- yokoyamai, Architectonica yokoyamai K. Oyama, 1954 - syn of: Architectonica oyamai O. Masuda & H. Noda, 1976 - (ARCHITECTONICIDAE)
- yokoyamai, Arca yokoyamai S. Nomura, 1933 - syn of: Verilarca interplicata (A.W. Grabau & S.G. King, 1928) - (ARCIDAE)
- yokoyamai, Baculites yokoyamai Tokunga & Shimizu, 1926 † - (BACULITIDAE) (FOSSIL)
- yokoyamai, Eocylindroteuthis yokoyamai Iba & al., 2014 † - (BELEMNITELLIDAE) (FOSSIL)
- yokoyamai, Neptunea yokoyamai K. Oyama, 1954 - (BUCCINIDAE)
- yokoyamai, Calyptraea yokoyamai J.T. Kuroda, 1929 - (CALYPTRAEIDAE)
- yokoyamai, Admete yokoyamai K. Oyama, 1954 † - syn of: Admete cancellata (Y. Otuka, 1937 †) - (CANCELLARIIDAE) (FOSSIL)
- yokoyamai, Capulus yokoyamai K. Oyama, 1954 † - (CAPULIDAE) (FOSSIL)
- yokoyamai, Yagudinella yokoyamai (Otuka 1935) † - (CARDIIDAE) (FOSSIL)
- yokoyamai, Nemocardium yokoyamai H. Takeda, 1953 † - (CARDIIDAE) (FOSSIL)
- yokoyamai, Serripes yokoyamai L.S. Zhidkova & al., 1972 † - (CARDIIDAE) (FOSSIL)
- yokoyamai, Cyclocardia yokoyamai K. Oyama & A. Mizuno, 1958 † - (CARDITIDAE) (FOSSIL)
- yokoyamai, Phalium yokoyamai S. Nomura & K.M. Hatai, 1936 † - (CASSIDAE) (FOSSIL)
- yokoyamai, Bittium yokoyamai Y. Otuka, 1936 † - (CERITHIIDAE) (FOSSIL)
- yokoyamai, Seila yokoyamai A.E.M. Cossmann, 1954 † - (CERITHIOPSIDAE) (FOSSIL)
- yokoyamai, Penicillus yokoyamai T. Shikama, 1954 - syn of: Nipponoclava gigantea (G.B. Sowerby, 1888) - (CLAVAGELLIDAE)
- yokoyamai, Corbula yokoyamai (T. Habe, 1949) - (CORBULIDAE)
- yokoyamai, Varicorbula yokoyamai T. Habe, 1949 - syn of: Corbula yokoyamai (T. Habe, 1949) - (CORBULIDAE)
- yokoyamai, Fissidentalium yokoyamai (J. Makiyama, 1931) - (DENTALIIDAE)
- yokoyamai, Turritoma yokoyamai N. Onoyama, 1933 † - syn of: Propebela yokoyamai (N. Onoyama, 1933 †) - (EOTOMARIIDAE) (FOSSIL)
- yokoyamai, Epitonium yokoyamai M. Suzuki & M. Ichikawa, 1936 - (EPITONIIDAE)
- yokoyamai, Niso yokoyamai J.T. Kuroda & T. Habe, 1950 - (EULIMIDAE)
- yokoyamai, Diodora yokoyamai K. Otsuka, 1937 - (FISSURELLIDAE)
- yokoyamai, Nipponomaria yokoyamai (I. Hayasaka, 1943 †) - (GOSSELETINIDAE) (FOSSIL)
- yokoyamai, Guizhouspira yokoyamai I. Hayasaka, 1943 † - syn of: Nipponomaria yokoyamai (I. Hayasaka, 1943 †) - (GOSSELETINIDAE) (FOSSIL)
- yokoyamai, Propebela yokoyamai (N. Onoyama, 1933 †) - (MANGELIIDAE) (FOSSIL)
- yokoyamai, Propebela yokoyamai K. Oyama, 1973 - syn of: Propebela assimilis (Sars, 1878) - (MANGELIIDAE)
- yokoyamai, Cancilla yokoyamai S. Nomura, 1935 - syn of: Cancilla isabella (W.J. Swainson, 1831) - (MITRIDAE)
- yokoyamai, Myadora yokoyamai T. Habe, 1950 - syn of: Myadora fluctuosa A.A. Gould, 1861 - (MYOCHAMIDAE)
- yokoyamai, Vaugonia yokoyamai Kobayashi & A. Mori, 1955 † - (MYOPHORELLIDAE) (FOSSIL)
- yokoyamai, Mytilus yokoyamai Slodkewitsch, 1936 † - (MYTILIDAE) (FOSSIL)
- yokoyamai, Crenella yokoyamai S. Nomura, 1932 - syn of: Crenella decussata (G. Montagu, 1808) - (MYTILIDAE)
- yokoyamai, Euspira yokoyamai (J.T. Kuroda & T. Habe, 1952) - (NATICIDAE)
- yokoyamai, Polinices yokoyamai J.T. Kuroda & T. Habe, 1952 - syn of: Euspira yokoyamai (J.T. Kuroda & T. Habe, 1952) - (NATICIDAE)
- yokoyamai, Nuculana yokoyamai J.T. Kuroda, 1934 - (NUCULANIDAE)
- yokoyamai, Loxoceras yokoyamai T. Kobayashi, 1928 † - (ORTHOCERIDA (UNASSIGNED)) (FOSSIL)
- yokoyamai, Canadoceras yokoyamai (Jimbo, 1894 †) - (PACHYDISCIDAE) (FOSSIL)
- yokoyamai, Nanonavis yokoyamai (Yabe & T. Nagao, 1965 †) - (PARALLELODONTIDAE) (FOSSIL)
- yokoyamai, Aelga yokoyamai J. Makiyama, 1934 † - syn of: Aelga besshoensis (M. Yokoyama, 1924 †) - (PERIPLOMATIDAE) (FOSSIL)
- yokoyamai, Pleurotomaria yokoyamai I. Hayasaka, 1943 † - syn of: Nipponomaria yokoyamai (I. Hayasaka, 1943 †) - (PLEUROTOMARIIDAE) (FOSSIL)
- yokoyamai, Vicarya yokoyamai T. Takeyama, 1933 † - (POTAMIDIDAE) (FOSSIL)
- yokoyamai, Treptoceras yokoyamai (Kobayashi, 1927 †) - (PROTEOCERATIDAE) (FOSSIL)
- yokoyamai, Comitas yokoyamai K. Oyama, 1954 - (PSEUDOMELATOMIDAE)
- yokoyamai, Odostomia yokoyamai S. Nomura, 1936 - (PYRAMIDELLIDAE)
- yokoyamai, Ringicula yokoyamai (T. Takeyama, 1935) - (RINGICULIDAE)
- yokoyamai, Ringiculina yokoyamai T. Takeyama, 1935 - syn of: Ringicula yokoyamai (T. Takeyama, 1935) - (RINGICULIDAE)
- yokoyamai, Timoclea yokoyamai T. Habe, 1947 - (VENERIDAE)
- yokoyamai arai, Nuculana yokoyamai arai T. Habe, 1958 - syn of: Nuculana arai T. Habe, 1958 - (NUCULANIDAE)
- yokoyamai koshibensis, Diodora yokoyamai koshibensis Y. Otuka, 1937 - (FISSURELLIDAE)
- yokoyamai krishtofovichae, Mytilus yokoyamai krishtofovichae Devjatilova, 1981 † - syn of: Mytilus krishtofovichae Devjatilova, 1981 † - (MYTILIDAE) (FOSSIL)
- Yokoyamaia, Genus Yokoyamaia T. Habe, 1950 (PHILINIDAE)
- Yokoyamaina, Genus Yokoyamaina Hayami, 1972 (CARDIIDAE) (FOSSIL)
- Yokoyamoceras, Genus Yokoyamoceras Matsumoto, 1955 (KOSSMATICERATIDAE) (FOSSIL)
- yolandae, Eubranchus yolandae A. Hermosillo & Á. Valdés, 2007 - (EUBRANCHIDAE)
- yolandae, Volvarina yolandae J. Espinosa & J.A. Ortea, 2000 - (MARGINELLIDAE)
- yolandae, Cypraeerato yolandae D. Fehse & J. Grego, 2012 † - (TRIVIIDAE) (FOSSIL)
- yolandia, Cancellaria yolandia H.A. Pilsbry & A.A. Olsson, 1941 † - (CANCELLARIIDAE) (FOSSIL)
- Yoldia, Genus Yoldia H.P.C. Mψller, 1842 (YOLDIIDAE)
- yoldiaformis, Technophorus yoldiaformis (Ulrich, 1879 †) - (TECHNOPHORIDAE) (FOSSIL)
- Yoldiella, Genus Yoldiella A.E. Verrill & K.J. Bush, 1897 (YOLDIIDAE)
- yoldiformis, Macoma yoldiformis P.P. Carpenter, 1864 - (TELLINIDAE)
- yoldii, Murex yoldii O.A.L. Mörch, 1852 - syn of: Hexaplex trunculus (C. Linnaeus, 1758) - (MURICIDAE)
- yoldii, Nerita yoldii C.A. Récluz, 1841 - (NERITIDAE)
- YOLDIIDAE Dall, 1908 - Family (BIVALVIA-PROTOBRANCHIA [Subclass]-NUCULANIDA [Order]-NUCULANOIDEA [Superfamily])
- yoldina, Columbella yoldina P.L. Duclos, 1840 - syn of: Anachis scalarina (G.B. I Sowerby, 1832) - (COLUMBELLIDAE)
- yoldina, Anachis yoldina P.L. Duclos, 1835 - syn of: Anachis scalarina (G.B. I Sowerby, 1832) - (COLUMBELLIDAE)
- Yoldioides, Genus Yoldioides Li & Grant-Mackie, 1994 (MALLETIIDAE) (FOSSIL)
- yolettae, Turbonilla yolettae L.G. Hertlein & A.M. Strong, 1951 - (PYRAMIDELLIDAE)
- yollabollium, Hoplocrioceras yollabollium Anderson, 1938 † - syn of: Crioceratites yollabollium Anderson, 1938 † - (ACRIOCERATIDAE) (FOSSIL)
- yollabollium, Crioceratites yollabollium Anderson, 1938 † - (CRIOCERATITIDAE) (FOSSIL)
- yoloensis, Desmophyllites yoloensis Anderson, 1958 † - syn of: Desmophyllites diphylloides (E. Forbes, 1846 †) - (DESMOCERATIDAE) (FOSSIL)
- yonabaruensis, Siphonalia yonabaruensis F.S. MacNeil, 1960 † - (BUCCINIDAE) (FOSSIL)
- yonabaruensis, Cancellaria yonabaruensis F.S. MacNeil, 1960 † - (CANCELLARIIDAE) (FOSSIL)
- yonabaruensis, Pseudolatirus yonabaruensis F.S. MacNeil, 1960 † - (FASCIOLARIIDAE) (FOSSIL)
- yonabaruensis, Cancilla yonabaruensis F.S. MacNeil, 1960 † - (MITRIDAE) (FOSSIL)
- yonabaruensis, Scaphander yonabaruensis F.S. MacNeil, 1960 † - (SCAPHANDRIDAE) (FOSSIL)
- yonakunijimana, Sinoennea yonakunijimana H.A. Pilsbry & Y. Hirase, 1909 - (DIAPHERIDAE)
- yonakunijimana, Diplommatina yonakunijimana H.A. Pilsbry & Y. Hirase, 1909 - (DIPLOMMATINIDAE)
- yonakunijimanus, Platyrhaphe hirasei yonakunijimanus J.T. Kuroda, 1960 - (CYCLOPHORIDAE)
- yonganense, Pernodoceras yonganense Wang, 1990 † - (PSEUDOTIROLITIDAE) (FOSSIL)
- yonganensis, Plectotropis yonganensis W.C. Zhou, Q. Xiao, C. Chen & C.C. Hwang, 2011 - (BRADYBAENIDAE)
- yonganensis, Pteria yonganensis Wang, 1993 † - (PTERIIDAE) (FOSSIL)
- yongdingensis, Palaeoneilo yongdingensis Li & Ding, 1982 † - (MALLETIIDAE) (FOSSIL)
- yongei, Trisidos yongei T. Iredale, 1939 - syn of: Trisidos tortuosa (C. Linnaeus, 1758) - (ARCIDAE)
- yongei, Crassatellopsis yongei Johnston, 1993 † - (CRASSATELLOPSIDAE) (FOSSIL)
- yongei, Doto yongei T.E. Thompson, 1972 - (DOTIDAE)
- yongei, Phaseolus yongei A. Sanders & J.A. Allen, 1973 - syn of: Microgloma yongei (A. Sanders & J.A. Allen, 1973) - (PHASEOLIDAE)
- yongei, Prochaetoderma yongei A.H. Scheltema, 1985 - (PROCHAETODERMATIDAE)
- yongei, Microgloma yongei (A. Sanders & J.A. Allen, 1973) - (YOLDIIDAE)
- yongei archeri, Trisidos yongei archeri T. Iredale, 1939 - syn of: Trisidos tortuosa (C. Linnaeus, 1758) - (ARCIDAE)
- yongei lamyi, Trisidos yongei lamyi T. Iredale, 1939 - syn of: Trisidos tortuosa (C. Linnaeus, 1758) - (ARCIDAE)
- yongei reevei, Trisidos yongei reevei T. Iredale, 1939 - syn of: Trisidos tortuosa (C. Linnaeus, 1758) - (ARCIDAE)
- yongguinia, Qiongzhounia yongguinia T.C. Lan, 1983 † - (NUCULANIDAE) (FOSSIL)
- Yonginella, Genus Yonginella Liljedahl, 1992 (CYRTODONTIDAE) (FOSSIL)
- yongkangensis, Valvata yongkangensis Yü, 1980 † - (VALVATIDAE) (FOSSIL)
- Yongkangia, Genus Yongkangia Yό, 1980 (HYDROBIIDAE) (FOSSIL)
- yonglingensis, Lufengospira yonglingensis Pan, 1977 † - (BITHYNIIDAE) (FOSSIL)
- yongpingense, Yongpingoceras yongpingense X.T. Ma & Li, 1998 † - syn of: Nodogastrioceras discum X.T. Ma & Li, 1998 † - (PARAGASTRIOCERATIDAE) (FOSSIL)
- Yongpingoceras, syn of: Genus Nodogastrioceras Ma & Li, 1998 (PARAGASTRIOCERATIDAE) (FOSSIL)
- yongshengensis, Pleurotomaria yongshengensis Pan, 1977 † - (PLEUROTOMARIIDAE) (FOSSIL)
- yongshuae, Megalauchenia yongshuae H. Nordsieck, 2007 - (CLAUSILIIDAE)
- yongshuae, Papilliphaedusa yongshuae H. Nordsieck, 2007 - (CLAUSILIIDAE)
- yonkersi, Lemniscolittorina yonkersi D.T. Dockery, 1993 † - (MATHILDIDAE) (FOSSIL)
- yonowae, Nembrotha yonowae B.G. Goethel & H. Debelius, 1992 - (POLYCERIDAE)
- yooi, Kimina yooi Frýda & K. Bandel, 1997 † - (ELASMONEMATIDAE) (FOSSIL)
- yooi, Austroneilsonia yooi Cook & A. Nützel, 2005 † - (GOSSELETINIDAE) (FOSSIL)
- yooi, Australoscutula yooi Cook & al., 2007 † - (PRAGOSCUTULIDAE) (FOSSIL)
- Yoospira, Genus Yoospira Bandel, 2002 (DONALDINIDAE) (FOSSIL)
- yoowadan, Globorhagada yoowadan F. Köhler, 2011 - (CAMAENIDAE)
- yoritomoi, Pyrgiscus yoritomoi (S. Nomura, 1938) - (PYRAMIDELLIDAE)
- yorkensis, Amplirhagada yorkensis F. Köhler, 2010 - (CAMAENIDAE)
- yorkensis, Columbella yorkensis J.C.H. Crosse, 1859 - syn of: Mitrella tayloriana yorkensis (J.C.H. Crosse, 1859) - (COLUMBELLIDAE)
- yorkensis, Mitrella tayloriana yorkensis (J.C.H. Crosse, 1859) - (COLUMBELLIDAE)
- yorkensis, Helicina yorkensis L. Pfeiffer, 1863 - syn of: Pleuropoma walkeri (E.A. Smith, 1894) - (HELICINIDAE)
- yorkensis, Cimomia yorkensis McGowran, 1959 † - syn of: Cimomia felix A.C. Chapman, 1915 † - (HERCOGLOSSIDAE) (FOSSIL)
- yorkensis, Kellia yorkensis (B.C. Cotton & F.C. Godfrey, 1938) - (KELLIIDAE)
- yorkensis, Lithophaga yorkensis A.A. Olsson, 1914 † - (MYTILIDAE) (FOSSIL)
- yorkensis, Argopecten eboreus yorkensis (T.A. Conrad, 1867 †) - (PECTINIDAE) (FOSSIL)
- yorkensis, Ilsanella yorkensis Parkhaev, 2001 † - (SCENELLIDAE) (FOSSIL)
- yorkensis, Truncatella yorkensis (J.C. Cox, 1868) - (TRUNCATELLIDAE)
- Yorkiella, syn of: Genus Horsegullia Parkhaev, 2004 (TRENELLIDAE) (FOSSIL)
- Yorkoceras, Genus Yorkoceras Flower, 1968 (ENDOCERIDA (UNASSIGNED)) (FOSSIL)
- yoroianum, Buccinum yoroianum H. Ozaki, 1958 - (BUCCINIDAE)
- yoroimana, Pupinella oshimae yoroimana H.A. Pilsbry & Y. Hirase, 1905 - (PUPINIDAE)
- yorojimaensis, Nesiohelix irrediviva yorojimaensis M. Azuma, 1990 - (BRADYBAENIDAE)
- yorojimana, Pupinella yorojimana H.A. Pilsbry & Y. Hirase, 1905 - (PUPINIDAE)
- yoronjimana, Satsuma yoronjimana M. Azuma, 1990 - (CAMAENIDAE)
- yoronjimana, Zaptyx hyperoptyx yoronjimana (H.A. Pilsbry, 1905) - (CLAUSILIIDAE)
- yosemitensis, Monadenia yosemitensis H.N. Lowe, 1916 - (MONADENIIDAE)
- yoshidai, Cyclocardia yoshidai T. Nagao, 1928 † - (CARDITIDAE) (FOSSIL)
- yoshidai, Lucinoma yoshidai T. Habe, 1958 - (LUCINIDAE)
- yoshidai, Gymnobela yoshidai (J.T. Kuroda & T. Habe, 1961) - (RAPHITOMIDAE)
- yoshidayukioi, Angustassiminea yoshidayukioi J.T. Kuroda, 1959 - (ASSIMINEIDAE)
- yoshidensis, Conus yoshidensis Kanno, 1958 † - (CONIDAE) (FOSSIL)
- yoshiharuyabei, Marmarostoma yoshiharuyabei M. Tomida & Kadota, 2010 † - (TURBINIDAE) (FOSSIL)
- yoshikoae, Pyrgiscus yoshikoae S. Hori & H. Fukuda, 1999 - (PYRAMIDELLIDAE)
- yoshimoensis, Paracorbicula yoshimoensis Ota 1965 † - (CARDIIDA (UNASSIGNED)) (FOSSIL)
- Yoshimonia, Genus Yoshimonia Ota, 1960 (THIARIDAE) (FOSSIL)
- Yoshimopsis, Genus Yoshimopsis Ohta, 1974 (BAKEVELLIIDAE) (FOSSIL)
- yoshimurai, Aspidopholas yoshimurai J.T. Kuroda & A. Teramachi, 1930 - (PHOLADIDAE)
- yoshioi, Rhizoconus yoshioi M. Azuma, 1973 - syn of: Kioconus sazanka (T. Shikama, 1970) - (CONIDAE)
- yoshioi, Phenacovolva yoshioi M. Azuma & C.N. Cate, 1971 - syn of: Calcarovula gracillima (E.A. Smith, 1901) - (OVULIDAE)
- yoshisadai, Pyrgiscus yoshisadai (S. Nomura, 1938) - (PYRAMIDELLIDAE)
- yoshisadai, Pyrgiscilla yoshisadai S. Nomura, 1938 - syn of: Pyrgiscus yoshisadai (S. Nomura, 1938) - (PYRAMIDELLIDAE)
- Yoshishigea, Genus Yoshishigea S. Hori & H. Fukuda, 1999 (PYRAMIDELLIDAE)
- yoshiwarai, Mikadotrochus yoshiwarai Oazki, 1954 † - (PLEUROTOMARIIDAE) (FOSSIL)
- yoshiwarana, Ogasawarana yoshiwarana (H.A. Pilsbry, 1902) - (HELICINIDAE)
- yoshiwarana arata, Ogasawarana yoshiwarana arata (H.A. Pilsbry, 1902) - (HELICINIDAE)
- yoshiwarana microtheca, Ogasawarana yoshiwarana microtheca (H.A. Pilsbry, 1902) - (HELICINIDAE)
- yosisadai, Turbonilla yosisadai S. Nomura, 1938 - (PYRAMIDELLIDAE)
- yositunei, Trabecula yositunei (S. Nomura, 1938) - (PYRAMIDELLIDAE)
aaa
abx
ack
acy
adn
aer
afs
ajd
alc
alj
alu
amc
ams
and
anh
anp
anu
apl
arb
ard
arh
ars
asr
atl
atu
aus
aut
bab
baj
bao
bas
baw
bem
bes
bid
bim
bit
bli
bom
bos
bov
bre
bri
bry
bum
bys
caa
cak
cam
cao
cas
cau
cem
ces
che
chk
chy
cio
cle
cob
coh
com
con
coo
cos
cot
cre
cri
cru
cud
cuo
cuy
cym
daa
dam
dav
ded
dem
deo
det
dib
dih
dir
dit
dom
dos
duc
duq
eag
ecr
egg
elf
elp
enh
eov
erf
erz
eud
eus
exb
exl
exy
faa
fan
fat
fes
fim
fle
flu
fos
fre
fuf
fur
fut
gaa
gam
gav
geo
gie
gis
gle
glu
goo
gre
gru
gug
guz
haa
ham
has
heb
hem
hes
hif
his
hom
hou
hun
hye
iac
ilm
imt
ind
inf
ing
int
inu
irm
isp
jaa
jao
jaw
joi
juk
kaa
kao
kaz
kes
kio
koc
kot
kuk
laa
lad
laf
lan
las
lau
lec
leo
leq
lew
lim
lio
liu
loo
lub
lun
luv
maa
mad
mah
mam
mao
mas
mav
mee
mem
mes
mey
mid
min
mio
mit
moe
moo
mos
mum
mut
nab
nao
nav
nel
neq
nex
nih
niu
noe
nou
nue
oaf
obn
obu
oci
oke
olk
oos
orc
oro
osu
ove
paa
paf
pam
paq
pas
pau
pay
pem
pes
pfi
phl
pid
pio
ple
plo
pom
pos
pre
pro
pru
psi
pul
pum
pup
put
pys
qag
qub
rab
rah
ras
red
reh
reu
rhu
rin
roc
rot
rox
rue
ruh
ryd
saa
sai
san
sao
sav
sce
sci
scy
sem
sen
ses
shl
sih
sin
sio
smo
som
soy
sph
spj
sra
stg
sts
suc
sum
suv
szo
tab
tal
taq
tay
ten
teo
tes
tha
thl
tif
toc
tos
tre
trl
try
tuc
tus
uac
ume
uni
urd
vaa
vap
vas
vep
ves
vid
vip
vis
vob
vup
waa
wam
weg
who
wom
xac
yaa
yot
zaa
zem
zoo
|