Asterina anomala H.L. Clark, 1921 accepted as Aquilonastra anomala (H.L. Clark, 1921) (original description)
Asterina nuda H.L. Clark, 1921 accepted as Indianastra sarasini (deLoriol, 1897) (original description)
Austrofromia H.L. Clark, 1921 accepted as Fromia Gray, 1840 (original description)
Bunaster uniserialis H.L. Clark, 1921 (original description)
Certonardoa H.L. Clark, 1921 (original description)
Comanthus alternans (Carpenter, 1881) accepted as Clarkcomanthus alternans (Carpenter, 1881) (new combination reference)
Ferdina ocellata H.L. Clark, 1921 accepted as Neoferdina cumingi (Gray, 1840) (original description)
Fromia elegans H.L. Clark, 1921 accepted as Fromia indica (Perrier, 1869) (original description)
Fromia hadracantha H.L. Clark, 1921 (original description)
Fromia japonica Perrier, 1881 accepted as Fromia monilis (Perrier, 1869) (source of synonymy)
Fromia pacifica H.L. Clark, 1921 (original description)
Habroporina H.L. Clark, 1921 accepted as Disasterina Perrier, 1875 (original description)
Habroporina pulchella H.L. Clark, 1921 accepted as Disasterina abnormalis Perrier, 1875 (original description)
Hacelia superba H.L. Clark, 1921 (original description)
Holothuria (Thymiosycia) impatiens var. pulchra Clark, 1921 accepted as Holothuria (Thymiosycia) impatiens (Forsskål, 1775) (original description)
Holothuria altimensis Clark, 1921 accepted as Holothuria (Platyperona) difficilis Semper, 1868 (original description)
Holothuria axiologa Clark, 1921 accepted as Holothuria (Microthele) fuscopunctata Jaeger, 1833 (original description)
Holothuria cumulus Clark, 1921 represented as Holothuria (Lessonothuria) cumulus Clark, 1921 (original description)
Holothuria hypamma Clark, 1921 accepted as Holothuria (Cystipus) inhabilis Selenka, 1867 (original description)
Holothuria impatiens var. concolor Clark, 1921 represented as Holothuria (Thymiosycia) impatiens var. concolor Clark, 1921 accepted as Holothuria (Thymiosycia) impatiens (Forsskål, 1775) (original description)
Holothuria impatiens var. lutea Clark, 1921 represented as Holothuria (Thymiosycia) impatiens var. lutea Clark, 1921 accepted as Holothuria (Thymiosycia) impatiens (Forsskål, 1775) (original description)
Holothuria subverta Clark, 1921 accepted as Holothuria (Metriatyla) martensii Semper, 1868 (original description)
Lamprometra protecta (Carpenter, 1879) accepted as Lamprometra palmata (Müller, 1841) accepted as Dichrometra palmata (Müller, 1841) (source of synonymy)
Leiaster brevispinus H.L. Clark, 1921 accepted as Leiaster leachi (Gray, 1840) (original description)
Leptosynapta latipatina Clark, 1921 (original description)
Linckia milleporella von Martens, 1866 accepted as Fromia monilis (Perrier, 1869) (source of synonymy)
Nardoa rosea H.L. Clark, 1921 (original description)
Neoferdina ocellata (H.L. Clark, 1921) accepted as Neoferdina cumingi (Gray, 1840) (original description)
Ophidiaster attenuatus Perrier, 1869 (status source)
Ophidiaster bicolor (Lamarck, 1816) (status source)
Ophidiaster lioderma H.L. Clark, 1921 accepted as Ophidiaster duncani de Loriol, 1885 (original description)
Ophiocoma brevipes var. longispina H.L. Clark, 1917 accepted as Ophiocoma longispina H.L. Clark, 1917 accepted as Breviturma longispina (H.L. Clark, 1917) (original description)
Ophiocoma crassispina (Say, 1825) accepted as Ophiocoma echinata (Lamarck, 1816) (source of synonymy)
Ophiocoma didelphys Wyville Thomson, 1876 accepted as Ophiacantha vivipara Ljungman, 1871 accepted as Ophiosabine vivipara (Ljungman, 1871) (source of synonymy)
Ophiocoma lubrica Koehler, 1898 accepted as Ophiocoma scolopendrina (Lamarck, 1816) (basis of record)
Ophiocoma molaris Lyman, 1861 accepted as Ophiocoma scolopendrina (Lamarck, 1816) (basis of record)
Ophiocoma variabilis Grube, 1857 accepted as Ophiocoma scolopendrina (Lamarck, 1816) (source of synonymy)
Ophiothrix martensi australis H.L. Clark, 1921 accepted as Macrophiothrix martensi australis (H.L. Clark, 1921) (original description)
Ophiura crassispina Say, 1825 accepted as Ophiocoma echinata (Lamarck, 1816) (source of synonymy)
Pentacta trimorpha Clark, 1921 accepted as Plesiocolochirus dispar (Lampert, 1889) (original description)
Plenardoa H.L. Clark, 1921 (original description)
Pseudocucumis eurystichus Clark, 1921 accepted as Mensamaria intercedens (Lampert, 1885) (original description)
Taeniogyrus dubius Clark, 1921 accepted as Sigmodota dubia (Clark, 1921) (original description)
Tamaria lithosora H.L. Clark, 1921 (original description)
Thelenota anax Clark, 1921 (original description)
Trochodota diasema Clark, 1921 accepted as Taeniogyrus diasemus (Clark, 1921) (original description)
Trochodota maculata Clark, 1921 accepted as Taeniogyrus maculatus (Clark, 1921) (original description)
Valvaster spinifera H.L. Clark, 1921 accepted as Valvaster striatus (Lamarck, 1816) (original description)