Agatha brevis Yokoyama, 1922 (original description)
Ancilla hinomotoensis Yokoyama, 1922 † accepted as Amalda hinomotoensis (Yokoyama, 1922) (original description)
Anomia lunula Yokoyama, 1922 accepted as Isomonia umbonata (A. Gould, 1861) (original description)
Anomia sematana Yokoyama, 1922 accepted as Isomonia umbonata (A. Gould, 1861) (original description)
Basilissa laeviuscula Yokoyama, 1922 accepted as Heterogen japonica (E. von Martens, 1861) accepted as Cipangopaludina japonica (E. von Martens, 1861) (original description)
Bulla multiarata Yokoyama, 1922 † accepted as Roxania punctulata (A. Adams, 1862) accepted as Mimatys punctulatus (A. Adams, 1862) (original description)
Cerithiopsis trisulcata Yokoyama, 1922 accepted as Cerithiella trisulcata (Yokoyama, 1922) (original description)
Chemnitzia kidoensis Yokoyama, 1922 accepted as Turbonilla kidoensis (Yokoyama, 1922) (original description)
Columbella (Atilia) smithi Yokoyama, 1922 † represented as Columbella smithi Yokoyama, 1922 † accepted as Mitrella tokyoensis Kuroda & Habe, 1954 † (original description)
Conotalopia sematensis (Oyama, 1942) (additional source)
Corbicula kobelti Yokoyama, 1922 † accepted as Corbicula (Corbicula) japonica Prime, 1864 represented as Corbicula japonica Prime, 1864 (original description)
Corbicula sandaiformis Yokoyama, 1922 † accepted as Corbicula (Corbicula) japonica Prime, 1864 represented as Corbicula japonica Prime, 1864 (original description)
Corbula frequens Yokoyama, 1922 accepted as Potamocorbula amurensis (Schrenck, 1862) (original description)
Corbula pustulosa Yokoyama, 1922 accepted as Potamocorbula amurensis (Schrenck, 1862) (original description)
Corbula pygmaea Yokoyama, 1922 accepted as Varicorbula yokoyamai Habe, 1949 (original description)
Corbula sematensis Yokoyama, 1922 accepted as Potamocorbula amurensis (Schrenck, 1862) (original description)
Corbula substriata Yokoyama, 1922 accepted as Corbula rotalis Hinds, 1843 accepted as Varicorbula rotalis (Hinds, 1843) (original description)
Crenella divaricata Yokoyama, 1922 accepted as Crenella decussata (Montagu, 1808) (original description)
Cryptomya busoensis Yokoyama, 1922 (original description)
Cucullaria orientalis Yokoyama, 1922 accepted as Porterius dalli (E. A. Smith, 1885) (original description)
Cuspidaria ligula Yokoyama, 1922 accepted as Plectodon ligula (Yokoyama, 1922) (original description)
Dentalium (Fustiaria) nipponicum Yokoyama, 1922 † accepted as Fustiaria nipponica (Yokoyama, 1922) (original description)
Emarginula vadososinuata Yokoyama, 1922 accepted as Scelidotoma vadososinuata (Yokoyama, 1922) accepted as Tugalina vadososinuata (Yokoyama, 1922) (original description)
Entodesma naviculoides Yokoyama, 1922 accepted as Entodesma navicula (A. Adams & Reeve, 1850) (original description)
Eulima ozawai Yokoyama, 1922 accepted as Eulima bifascialis (A. Adams, 1863) (original description)
Eulima tokunagai Yokoyama, 1922 accepted as Hypermastus tokunagai (Yokoyama, 1922) (original description)
Eulima unicincta Yokoyama, 1922 (original description)
Genotia ogurana Yokoyama, 1922 accepted as Ophiodermella ogurana (Yokoyama, 1922) (original description)
Jouannetia kamakurensis Yokoyama, 1922 accepted as Penitella gabbii (Tryon, 1863) (original description)
Leptothyra pygmaea Yokoyama, 1922 accepted as Lirularia pygmaea (Yokoyama, 1922) (original description)
Lima vulgatula Yokoyama, 1922 (original description)
Limopsis areolata Yokoyama, 1922 accepted as Limopsis (Empleconia) cumingi A. Adams, 1863 represented as Limopsis cumingi A. Adams, 1863 (original description)
Limopsis nipponica Yokoyama, 1922 (original description)
Mactra dunkeri Yokoyama, 1922 accepted as Spisula sachalinensis (Schrenck, 1862) accepted as Spisula sibyllae (Valenciennes, 1858) (original description)
Mactra sachalinensis var. imperialis Yokoyama, 1922 accepted as Spisula sachalinensis (Schrenck, 1862) accepted as Spisula sibyllae (Valenciennes, 1858) (original description)
Mangilia (Cythara) oyuana Yokoyama, 1922 † accepted as Ithycythara oyuana (Yokoyama, 1922) (original description)
Marginella cotamago Yokoyama, 1922 accepted as Granulina cotamago (Yokoyama, 1922) (original description)
Marginella perovulum Yokoyama, 1922 † accepted as Hyalina perovula (Yokoyama, 1922) † (original description)
Mitra hondana Yokoyama, 1922 accepted as Microvoluta hondana (Yokoyama, 1922) (original description)
Mitra pirula Yokoyama, 1922 accepted as Microvoluta hondana (Yokoyama, 1922) (original description)
Mitrella turriculata Yokoyama, 1922 (original description)
Montacuta japonica Yokoyama, 1922 accepted as Montacutona japonica (Yokoyama, 1922) (original description)
Montacuta oblongata Yokoyama, 1922 accepted as Nipponomysella oblongata (Yokoyama, 1922) (original description)
Montacuta yamakawai Yokoyama, 1922 accepted as Borniopsis yamakawai (Yokoyama, 1922) (original description)
Odostomia (Egilina) marielloides Yokoyama, 1922 accepted as Parthenina marielloides (Yokoyama, 1922) (original description)
Odostomia (Odetta) neofelix Yokoyama, 1922 accepted as Iolaea neofelix (Yokoyama, 1922) (original description)
Odostomia (Odostomia) gordonis Yokoyama, 1922 accepted as Megastomia gordonis (Yokoyama, 1922) (original description)
Odostomia (Odostomia) suboxia Yokoyama, 1922 accepted as Odostomia suboxia Yokoyama, 1922 (original description)
Odostomia shimosensis Yokoyama, 1922 (original description)
Olivella spretoides Yokoyama, 1922 (original description)
Pecten tenuicostulatus Yokoyama, 1922 † accepted as Parvamussium intuscostatum (Yokoyama, 1920) (original description)
Pectunculus yamakawai Yokoyama, 1922 accepted as Glycymeris rotunda (Dunker, 1882) (original description)
Philine pygmaea Yokoyama, 1922 † accepted as Yokoyamaia (Choshiphiline) pygmaea (Yokoyama, 1922) † (original description)
Poromya flexuosa Yokoyama, 1922 (original description)
Psammobia kazusensis Yokoyama, 1922 accepted as Gari kazusensis (Yokoyama, 1922) (original description)
Psammocola kazusensis Yokoyama, 1922 accepted as Gari kazusensis (Yokoyama, 1922) (original description)
Pyramidella (Iphiana) mira Yokoyama, 1922 accepted as Iphiana mira (Yokoyama, 1922) (original description)
Raeta elliptica Yokoyama, 1922 accepted as Raeta pulchella (A. Adams & Reeve, 1850) (original description)
Raeta magnifica Yokoyama, 1922 accepted as Raeta pellicula (Reeve, 1854) (original description)
Rissoa plebeja Yokoyama, 1922 † (original description)
Rissoina (Moerchiella) manzakiana Yokoyama, 1922 † accepted as Rugadentia manzakiana (Yokoyama, 1922) (original description)
Rissoina manzakiana Yokoyama, 1922 † accepted as Moerchiella manzakiana (Yokoyama, 1922) † (original description)
Scalaria azumana Yokoyama, 1922 accepted as Epitonium eximium (A. Adams & Reeve, 1850) (original description)
Scalaria conjuncta Yokoyama, 1922 accepted as Epitonium conjunctum (Yokoyama, 1922) (original description)
Scalaria kazusensis Yokoyama, 1922 accepted as Epitonium kazusense (Yokoyama, 1922) (original description)
Scalaria maculosa Yokoyama, 1922 accepted as Epitonium stigmaticum (Pilsbry, 1911) (original description)
Scalaria picturata Yokoyama, 1922 † accepted as Amaea thielei (de Boury, 1913) (original description)
Scalaria yamakawai Yokoyama, 1922 accepted as Epitonium yamakawai (Yokoyama, 1922) (original description)
Sipho (Parasipho) nipponicus Yokoyama, 1922 † accepted as Oenopota nipponica (Yokoyama, 1922) † (original description)
Tellina alternata chibana Yokoyama, 1922 accepted as Megangulus venulosus (Schrenck, 1861) (original description)
Tellina delta Yokoyama, 1922 accepted as Cadella delta (Yokoyama, 1922) (original description)
Terebra tsuboiana Yokoyama, 1922 † accepted as Pristiterebra tsuboiana (Yokoyama, 1922) † (original description)
Thracia sematana Yokoyama, 1922 accepted as Parvithracia sematana (Yokoyama, 1922) (original description)
Thracia transmontana Yokoyama, 1922 accepted as Myadoropsis transmontana (Yokoyama, 1922) (original description)
Thyasira trigonata Yokoyama, 1922 accepted as Simplicicordia trigonata (Yokoyama, 1922) (original description)
Torinia elegantula Yokoyama, 1922 † accepted as Pseudotorinia amoena (Murdoch & Suter, 1906) (original description)
Trapezium nipponicum Yokoyama, 1922 accepted as Neotrapezium liratum (Reeve, 1843) (original description)
Trapezium ventricosum Yokoyama, 1922 accepted as Neotrapezium liratum (Reeve, 1843) (original description)
Triforis multigyrata Yokoyama, 1922 † accepted as Latitriphora multigyrata (Yokoyama, 1922) † (original description)
Turbonilla (Ptycheulimella) misella Yokoyama, 1922 accepted as Ptycheulimella misella (Yokoyama, 1922) (original description)
Turbonilla (Pyrgolampros) planicostata Yokoyama, 1922 accepted as Turbonilla planicostata Yokoyama, 1922 (original description)
Turbonilla (Strioturbonilla) pacifica Yokoyama, 1922 accepted as Pyrgiscus pacificus (Yokoyama, 1922) (original description)
Turbonilla (Strioturbonilla) sagamiana Yokoyama, 1922 accepted as Parthenina sagamiana (Yokoyama, 1922) (original description)
Turbonilla angulifera Yokoyama, 1922 accepted as Aclis angulifera (Yokoyama, 1922) (original description)
Turbonilla imbana Yokoyama, 1922 (original description)
Turbonilla planicostata Yokoyama, 1922 (original description)
Turbonilla scrobiculata Yokoyama, 1922 (original description)
Turbonilla teganumana Yokoyama, 1922 (original description)
Venericardia toneana Yokoyama, 1922 accepted as Carditellopsis toneana (Yokoyama, 1922) (original description)
Venus neastartoides Yokoyama, 1922 accepted as Gomphinella neastartoides (Yokoyama, 1922) accepted as Gomphina neastartoides (Yokoyama, 1922) (original description)
Volvula acutaeformis Yokoyama, 1922 † accepted as Volvulella ovulina (A. Adams, 1862) (original description)
Yoldia notabilis Yokoyama, 1922 (original description)

Honshu for Basilissa laeviuscula Yokoyama, 1922 
Honshu for Columbella (Atilia) smithi Yokoyama, 1922 † 
Honshu for Corbicula kobelti Yokoyama, 1922 † 
Honshu for Corbicula sandaiformis Yokoyama, 1922 † 
Honshu for Marginella cotamago Yokoyama, 1922 

 Type locality

 for Corbicula kobelti Yokoyama, 1922 †

"Shito, Otake" (Honshu, Japan) [details]

 Type locality

 for Corbicula sandaiformis Yokoyama, 1922 †

"Otake, Kamenari, Shito" (Honshu, Japan) [details]