• Scalebrina Conil & Longerstaey, 1980 †
• Scalebrina austini Conil & Longerstaey, 1980 † accepted as Quasilituotuba austini (Conil & Longerstaey, 1980) †
• Scalebrina compacta Conil & Longerstaey, 1980 †
• Scalebrina complanata Conil & Longerstaey, 1980 †
• Scalebrina erecta Conil & Longerstaey, 1980 †
• Scalenaria Rafinesque, 1820 accepted as Pleurobema Rafinesque, 1819
• Scalenaria mangikiani (Jatsko, 1954) † accepted as Betekeia mangikiani (Jatsko, 1954) †
• Scalenaria pontica (Jatsko, 1954) † accepted as Betekeia pontica (Jatsko, 1954) †
• Scalenaria pseudonovorossica (Jatsko, 1954) † accepted as Betekeia pseudonovorossica (Jatsko, 1954) †
• Scalenaria ptychodes (Brusina, 1874) † accepted as Potomida bielzi (Czekelius, 1864) †
• Scalenaria sinzovi (Bogachev, 1924) † (uncertain > unassessed)
• Scalenaria subpontica (Jatsko, 1954) † accepted as Psilunio subponticus (Jatsko, 1954) †
• Scalenilla Ortmann & Walker, 1922 accepted as Epioblasma Rafinesque, 1831
• Scalenostoma Deshayes, 1863
• Scalenostoma (Hyperlia) Pilsbry, 1917 accepted as Scalenostoma Deshayes, 1863
• Scalenostoma (Hyperlia) apiculatum Souverbie, 1876 accepted as Scalenostoma apiculatum Souverbie, 1876 accepted as Scalenostoma carinatum Deshayes, 1863
• Scalenostoma abbreviata (Mörch, 1875) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma apiculatum Souverbie, 1876 accepted as Scalenostoma carinatum Deshayes, 1863
• Scalenostoma babylonia (Bartsch, 1912)
• Scalenostoma carinatum Deshayes, 1863
• Scalenostoma corallina (Chemnitz, 1795) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma cumingiana (A. Adams, 1878) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma deshayesii A. Adams, 1870 accepted as Scalenostoma carinatum Deshayes, 1863
• Scalenostoma hawaiiensis (Pilsbry, 1921) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma latior (Pilsbry, 1917) accepted as Scalenostoma carinatum Deshayes, 1863
• Scalenostoma lodderae (Petterd, 1884)
• Scalenostoma lubricum P. Fischer, 1886 accepted as Scalenostoma carinatum Deshayes, 1863
• Scalenostoma mariei P. Fischer, 1886 (uncertain > taxon inquirendum)
• Scalenostoma perrierae Barros, Padovan & Santos, 2001
• Scalenostoma pyramidata Laseron, 1951 accepted as Megastomia pyramidata (Laseron, 1951)
• Scalenostoma remotissimus (Pilsbry, 1921) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma robusta (Petterd, 1884) accepted as Scalenostoma lodderae (Petterd, 1884)
• Scalenostoma southlandica Laws, 1940 † accepted as Parodostomia southlandica (Laws, 1940) †
• Scalenostoma striatum Hedley, 1905 accepted as Trochostilifer striatus (Hedley, 1905)
• Scalenostoma subcarina Laseron, 1951 accepted as Megastomia subcarina (Laseron, 1951)
• Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma suteri W. R. B. Oliver, 1915 accepted as Teretianax suteri (W. R. B. Oliver, 1915)
• Scalenostoma thomasiae (Sowerby, 1878) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalenostoma thomasii (Sowerby, 1884) accepted as Scalenostoma subulatum (Broderip, 1832)
• Scalesia Arn. ex Arn.
• Scalesia affinis Hook.f.
• Scalesia affinis subsp. affinis accepted as Scalesia affinis Hook.f.
• Scalesia affinis subsp. brachyloba Harling accepted as Scalesia affinis Hook.f.
• Scalesia affinis subsp. gummifera (Hook.f.) Harling accepted as Scalesia affinis Hook.f.
• Scalesia aspera Andersson
• Scalesia aspera var. aspera accepted as Scalesia aspera Andersson
• Scalesia aspera var. subintegerrima Harling accepted as Scalesia aspera Andersson
• Scalesia atractyloides Arn.
• Scalesia atractyloides var. atractyloides
• Scalesia atractyloides var. darwinii (Hook.f.) Eliasson
• Scalesia baurii B.L.Rob. & Greenm.
• Scalesia baurii subsp. bauri
• Scalesia baurii subsp. hopkinsii (B.L.Rob.) Eliasson
• Scalesia baurii var. baurii accepted as Scalesia baurii B.L.Rob. & Greenm.
• Scalesia baurii var. glabrata B.L.Rob. accepted as Scalesia baurii B.L.Rob. & Greenm.
• Scalesia cordata A.Stewart (uncertain > unassessed)
• Scalesia crockeri Howell (uncertain > unassessed)
• Scalesia crockeri J.T.Howell (uncertain > unassessed)
• Scalesia darwinii Hook.f. accepted as Scalesia atractyloides Arn.
• Scalesia decurrens Andersson accepted as Scalesia affinis Hook.f.
• Scalesia decurrens f. decurrens accepted as Scalesia decurrens Andersson accepted as Scalesia affinis Hook.f.
• Scalesia decurrens f. denudata Andersson accepted as Scalesia affinis Hook.f.
• Scalesia divisa Andersson accepted as Scalesia incisa Hook.f.
• Scalesia gordilloi O. Hamann & Wium-And. (uncertain > unassessed)
• Scalesia gordilloi O.J.Hamann & Wium-And. (uncertain > unassessed)
• Scalesia gummifera Hook.f. accepted as Scalesia affinis Hook.f.
• Scalesia helleri B.L.Rob.
• Scalesia helleri subsp. helleri accepted as Scalesia helleri B.L.Rob.
• Scalesia helleri subsp. santacruzensis Harling (uncertain > unassessed)
• Scalesia helleri subsp. santacruziana Harling accepted as Scalesia helleri B.L.Rob.
• Scalesia hopkinsii B.L.Rob. accepted as Scalesia baurii B.L.Rob. & Greenm.
• Scalesia incisa Hook.f.
• Scalesia menziesii (Degener & Sherff) accepted as Scalesia affinis Hook.f.
• Scalesia menziesii (O.Deg. & Sherff) O.Deg. & Sherff (uncertain > unassessed)
• Scalesia microcephala B.L.Rob.
• Scalesia microcephala var. cordifolia Eliasson (uncertain > unassessed)
• Scalesia microcephala var. microcephala accepted as Scalesia microcephala B.L.Rob.
• Scalesia narbonensis B.L.Rob. accepted as Scalesia affinis Hook.f.
• Scalesia ovata Andersson accepted as Scalesia pedunculata Hook.f.
• Scalesia pedunculata Hook.f.
• Scalesia pedunculata var. indurata J.T.Howell accepted as Scalesia pedunculata Hook.f.
• Scalesia pedunculata var. parviflora J.T.Howell accepted as Scalesia pedunculata Hook.f.
• Scalesia pedunculata var. pedunculata accepted as Scalesia pedunculata Hook.f.
• Scalesia pedunculata var. pilosa J.T.Howell accepted as Scalesia pedunculata Hook.f.
• Scalesia pedunculata var. svensonii J.T.Howell accepted as Scalesia pedunculata Hook.f.
• Scalesia pedunculata var. typica J.T.Howell (uncertain > unassessed)
• Scalesia retroflexa Hemsl. accepted as Scalesia incisa Hook.f.
• Scalesia snodgrassii B.L.Rob. accepted as Scalesia incisa Hook.f.
• Scalesia stewartii L.Riley (uncertain > unassessed)
• Scalesia stewartii Riley
• Scalesia stewartii var. euryphylla Harling accepted as Scalesia stewartii Riley
• Scalesia stewartii var. stewartii accepted as Scalesia stewartii Riley
• Scalesia villosa Stewart
• Scalesia villosa Stewart & J.T.Howell (uncertain > unassessed)
• Scalesia villosa var. championensis A.Stewart accepted as Scalesia villosa Stewart
• Scalesia villosa var. villosa accepted as Scalesia villosa Stewart
• Scalez G. D. Hanna & Gaylord, 1924 †
• Scalez petrolia G. D. Hanna & Gaylord, 1924 †