Polymastia is een geslacht van sponsdieren uit de klasse van de Demospongiae (gewone sponzen).
Soorten Polymastia actinioides Koltun, 1966 Polymastia affinis Thiele, 1898 Polymastia agglutinans Ridley & Dendy, 1886 Polymastia andrica de Laubenfels, 1949 Polymastia arctica (Merejkowsky, 1878) Polymastia atlantica Samaai & Gibbons, 2005 Polymastia aurantia Kelly-Borges & Bergquist, 1997 Polymastia azorica Lévi & Vacelet, 1958 Polymastia bartletti de Laubenfels, 1942 Polymastia bicolor Carter, 1886 Polymastia boletiformis (Lamarck, 1815) Polymastia bouryesnaultae Samaai & Gibbons, 2005 Polymastia clavata Burton, 1959 Polymastia conigera Bowerbank, 1874 Polymastia corticata Ridley & Dendy, 1886 Polymastia crassa Carter, 1886 Polymastia craticia Hallmann, 1912 Polymastia crocea Kelly-Borges & Bergquist, 1997 Polymastia dendyi Whitelegge, 1897 Polymastia disclera Lévi, 1964 Polymastia echinus Kelly-Borges & Bergquist, 1997 Polymastia ectofibrosa Boury-Esnault, Pansini & Uriz, 1994 Polymastia nivea (Hansen, 1885) Polymastia fluegeli Lehnert, Stone & Heimler, 2005 Polymastia fordei Lehnert & van Soest, 1999 Polymastia fusca Bergquist, 1961 Polymastia gemmipara Dendy, 1916 Polymastia granulosa Brøndsted, 1924 Polymastia grimaldii (Topsent, 1913) Polymastia harmelini Boury-Esnault & Bézac, 2007 Polymastia hirsuta Bergquist, 1968 Polymastia hispidissima Koltun, 1966 Polymastia inflata Cabioch, 1968 Polymastia infrapilosa Topsent, 1927 Polymastia invaginata Kirkpatrick, 1907 Polymastia isidis Thiele, 1905 Polymastia janeirensis (Boury-Esnault, 1973) Polymastia kurilensis Koltun, 1962 Polymastia laganoides Lambe, 1895 Polymastia littoralis Stephens, 1915 Polymastia lorum Kelly-Borges & Bergquist, 1997 Polymastia maeandria Wilson, 1904 Polymastia mamillaris (Müller, 1806) Polymastia martae Boury-Esnault, Pansini & Uriz, 1994 Polymastia massalis Carter, 1886 Polymastia megasclera Burton, 1934 Polymastia murrayi Burton, 1959 Polymastia nigra Alcolado, 1984 Polymastia pachymastia de Laubenfels, 1932 Polymastia pacifica Koltun, 1966 Polymastia pacifica Lambe, 1893 Polymastia paupera Fristedt, 1887 Polymastia penicillus (Montagu, 1814) Polymastia pepo Kelly-Borges & Bergquist, 1997 Polymastia piscesae Austin, Ott, Reiswig, Romagosa & McDaniel, 2014 Polymastia polytylota Vacelet, 1969 Polymastia radiosa Bowerbank, 1866 Polymastia rara Koltun, 1966 Polymastia rubens Kelly-Borges & Bergquist, 1997 Polymastia simplicissima Thiele, 1898 Polymastia sola Pulitzer-Finali, 1983 Polymastia spinula Bowerbank, 1866 Polymastia tapetum Kelly-Borges & Bergquist, 1997 Polymastia tenax Pulitzer-Finali, 1986 Polymastia thielei Koltun, 1964 Polymastia tissieri (Vacelet, 1961) Polymastia toporoki Koltun, 1966 Polymastia tropicalis Lévi, 1967 Polymastia tubulifera Dendy, 1922 Polymastia uberrima (Schmidt, 1870) Polymastia umbraculum Kelly-Borges & Bergquist, 1997 Polymastia varia Verrill, 1907 Polymastia villosa Desqueyroux-Faúndez & van Soest, 1997 Polymastia zitteli (Lendenfeld, 1888)