• Aaptos suberitoides (Brøndsted, 1934)
• Acanthella cavernosa Dendy, 1922
• Acanthocinachyra enigmatica Lévi, 1964 accepted as Acanthotetilla enigmatica (Lévi, 1964)
• Acarnus (Acanthacarnus) souriei Lévi, 1952 accepted as Acarnus souriei (Lévi, 1952)
• Acarnus topsenti Dendy, 1922
• Acheliderma lemniscatum Topsent, 1892
• Adocia digitata (Baer, 1906) accepted as Haliclona (Haliclona) leopoldi Van Soest & Hooper, 2020
• Adocia simplicissima Burton, 1933 accepted as Haliclona simplicissima (Burton, 1933)
• Agelas ceylonica Dendy, 1905
• Aka insidiosa (Johnson, 1899) accepted as Siphonodictyon insidiosum (Johnson, 1899)
• Alloscleria tenuispinosa Topsent, 1927
• Amorphinopsis oculata (Kieschnick, 1896) accepted as Amorphinopsis fenestrata (Ridley, 1884)
• Aaptos nuda (Kirkpatrick, 1903)
• Acanthella aurantiaca Keller, 1889 accepted as Stylissa carteri (Dendy, 1889)
• Acantheurypon pilosella (Topsent, 1904)
• Acanthotriaena crypta Vacelet, Vasseur & Lévi, 1976
• Acarnus ternatus Ridley, 1884
• Acervochalina limbata (Montagu, 1814) accepted as Chalinula limbata (Montagu, 1814)
• Adocia cinerea (Grant, 1826) accepted as Haliclona (Reniera) cinerea (Grant, 1826)
• Adocia pigmentifera (Dendy, 1905) accepted as Haliclona pigmentifera (Dendy, 1905)
• Agelas bispiculata Vacelet, Vasseur & Lévi, 1976
• Aka coralliirubri Calcinai, Cerrano & Bavestrello, 2007 accepted as Siphonodictyon coralliirubri (Calcinai, Cerrano & Bavestrello, 2007)
• Alectona verticillata (Johnson, 1899)
• Amorphinopsis foetida (Dendy, 1889)
• Amphilectus fucorum (Esper, 1794)
• Aaptos papillata (Keller, 1880)
• Acanthella carteri Dendy, 1889 accepted as Stylissa carteri (Dendy, 1889)
• Acantheurypon spinispinosum (Topsent, 1904)
• Acanthoxifer fourmanoiri Lévi, 1956 accepted as Myrmekioderma granulatum (Esper, 1829)
• Acarnus thielei Lévi, 1958
• Acervochalina parasimulans (Lévi, 1959) accepted as Chalinula parasimulans (Lévi, 1959)
• Adocia dendyi (Burton, 1931) accepted as Callyspongia (Toxochalina) dendyi (Burton, 1931)
• Adocia semifibrosa (Dendy, 1916) accepted as Haliclona semifibrosa (Dendy, 1916)
• Agelas carpenteri (Gray, 1867) (uncertain > taxon inquirendum)
• Aka infesta (Johnson, 1889) accepted as Siphonodictyon infestum (Johnson, 1899)
• Alectona wallichii (Carter, 1874)
• Amorphinopsis megalorrhaphis (Carter, 1881) accepted as Topsentia megalorrhapis (Carter, 1881)
• Aaptos alphiensis Samaai & Gibbons, 2005
• Acanthella acuta Schmidt, 1862
• Acanthella klethra Pulitzer-Finali, 1982
• Acanthotetilla hemisphaerica Burton, 1959
• Acarnus levii (Vacelet, 1960)
• Acca insidiosa Johnson, 1899 accepted as Siphonodictyon insidiosum (Johnson, 1899)
• Aciculites tulearensis Vacelet & Vasseur, 1965
• Adocia fragilis Vacelet, Vasseur & Lévi, 1976 accepted as Haliclona fragilis (Vacelet, Vasseur & Lévi, 1976)
• Adreissa labellum (Lamarck, 1814) accepted as Phakellia labellum (Lamarck, 1814)
• Agelas oroides (Schmidt, 1864)
• Alectona millari Carter, 1879
• Amorphinopsis filigrana (Schmidt, 1862)
• Amphilectus caducum (Schmidt, 1868) accepted as Lissodendoryx (Lissodendoryx) caduca (Schmidt, 1868)
• Aaptos chromis de Laubenfels, 1954 accepted as Aaptos suberitoides (Brøndsted, 1934)
• Acanthella annulata Sarà, 1958
• Acanthella obtusa Schmidt, 1862 accepted as Dictyonella obtusa (Schmidt, 1862)
• Acanthotetilla seychellensis (Thomas, 1973)
• Acarnus souriei (Lévi, 1952)
• Acca rodens Johnson, 1899 accepted as Siphonodictyon insidiosum (Johnson, 1899)
• Adocia atra Pulitzer-Finali, 1993 accepted as Haliclona (Reniera) atra (Pulitzer-Finali, 1993)
• Adocia intersepta (Topsent, 1928) accepted as Siphonochalina intersepta (Topsent, 1928)
• Adreus micraster (Burton, 1956)
• Agelas oxeata Lévi, 1961
• Alectona primitiva Topsent, 1932
• Amorphinopsis fistulosa (Vacelet, Vasseur & Lévi, 1976)
• Amphilectus columnatus (Topsent, 1890)
• Aaptos aaptos (Schmidt, 1864)
• Acanthancora stylifera Burton, 1959
• Acanthella flabelliformis Keller, 1889 accepted as Echinodictyum flabelliforme (Keller, 1889)
• Acanthotetilla enigmatica (Lévi, 1964)
• Acarnus claudei van Soest, Hooper & Hiemstra, 1991
• Acca infesta Johnson, 1899 accepted as Siphonodictyon infestum (Johnson, 1899)
• Aciculites spinosa Vacelet & Vasseur, 1971
• Adocia flagellifera (Ridley & Dendy, 1886) accepted as Haliclona (Flagellia) flagellifera (Ridley & Dendy, 1886)
• Adocia tufa (Ridley & Dendy, 1886) accepted as Calyx tufa (Ridley & Dendy, 1886)
• Agelas mauritiana var. oxeata Lévi, 1961 accepted as Agelas oxeata Lévi, 1961
• Aka rodens (Johnson, 1899) accepted as Siphonodictyon insidiosum (Johnson, 1899)
• Amorphinopsis fenestrata (Ridley, 1884)
• Amphibleptula hirsuta (Kirkpatrick, 1903) accepted as Microscleroderma hirsutum Kirkpatrick, 1903
• Acanthancora schmidti (Topsent, 1898)
• Acanthella elongata (Dendy, 1905) accepted as Auletta elongata Dendy, 1905
• Acanthostylotella cornuta (Topsent, 1897)
• Acarnus bicladotylotus Hoshino, 1981
• Acarnus wolffgangi Keller, 1889
• Aciculites cribrophora (Schmidt, 1880)
• Adocia fistulosa Pulitzer-Finali, 1993 accepted as Haliclona (Haliclona) gustavopulitzeri Van Soest & Hooper, 2020
• Adocia spiculotenuis (Topsent, 1891) accepted as Haliclona spiculotenuis (Topsent, 1891)
• Agelas mauritiana (Carter, 1883)
• Aka minuta Thomas, 1972 accepted as Siphonodictyon minutum (Thomas, 1972)
• Amorphinopsis excavans Carter, 1887
• Amorphinopsis reptans (Kirkpatrick, 1903) accepted as Protosuberites reptans (Kirkpatrick, 1903)
• Acanthacarnus souriei Lévi, 1952 accepted as Acarnus souriei (Lévi, 1952)
• Acanthella ehrenbergi Keller, 1889 accepted as Biemna ehrenbergi (Keller, 1889)
• Acanthocinachyra seychellensis Thomas, 1973 accepted as Acanthotetilla seychellensis (Thomas, 1973)
• Acarnus bergquistae van Soest, Hooper & Hiemstra, 1991
• Acarnus tortilis Topsent, 1892
• Acheliderma planum (Topsent, 1927)
• Adocia fayalensis (Topsent, 1892) accepted as Gelliodes fayalensis Topsent, 1892
• Adocia simulans (Johnston, 1842) accepted as Haliclona (Haliclona) simulans (Johnston, 1842)
• Agelas marmarica Lévi, 1958
• Aka labyrinthica (Hancock, 1849) accepted as Siphonodictyon labyrinthicum (Hancock, 1849)
• Amorphina isthmica Keller, 1883 represented as Halichondria (Halichondria) isthmica (Keller, 1883)
• Amorphinopsis pallescens (Topsent, 1892)