Lens Simpson, 1900
Simpson, 1900, Proc. U.S. Nat. Mus. 22: 831.
Simpson, 1914, Descr. Cat. Naiades: 1067.
(intro'd as sub-gen. of Physunio Simpson, 1900)
Type species: Unio eximius Lea, 1856 (orig. desig.) = Lens eximius

Contradens Haas, 1911
Haas, 1911, Conch. Cab. 9 (pt. 2, h. 44): pl. 18-22.
Haas, 1913, Nachr. Bl. Dtsch. Malak. Ges. 45: 35.
Haas, 1913, Conch. Cab. 9 (pt. 2, h. 48): 173.
Type species: Unio contradens Lea, 1838 (orig. desig.) = Lens contradens

Schizocleithrum Haas, 1913
Haas, 1911, Conch. Cab. 9 (pt. 2, h. 44): pl. 22.
Haas, 1913, Nachr. Bl. Dtsch. Malak. Ges. 45: 36.
Haas, 1914, Conch. Cab. 9 (pt. 2, h. 49): 202.
Type species: Unio pajakomboensis Bullen, 1906 (orig. desig.) = Lens contradens

Uniandra Haas, 1913
Haas, 1913, Conch. Cab. 9 (pt. 2, h. 47): 140.
(intro'd as sub-gen. of Ensidens Frierson, 1911)
Type species: Unio inaequalis Rochebrune, 1882 (orig. desig.) = Lens micropterus

Sprickia Modell, 1942
Modell, 1942, Arch. Moll. 74(5/6): 189.
Modell, 1964, Arch. Moll. 93: 114.
(intro'd as sub-gen. of Contradens Haas, 1911)
Type species: Unio verbecki Martens, 1897 (orig. desig.) = Lens contradens

Sprichia Vokes, 1980
‘Modell’ of Authors.
Vokes, 1980, Genera of the Bivalvia: 78.
Vaught, 1989, Class. Livinh Moll.: 122.
Millard, 2001, Class. Moll. (3): 1064.
(error for Sprickia Modell, 1942)

Contortus Araujo et al., 2017
Araujo et al., 2017, Zool. J. Linn. Soc. 179(2): 280.
(error for Contradens Haas, 1911)

Taxonomic History (since 1900)

Nodularia (s.s.) — Simpson (1900), Simpson (1914)
Physunio (s.s.) — Simpson (1900), Preston (1912), Simpson (1914), Haas (1919), Haas (1924), Haas (1952), Haas (1969)
Physunio (sec. Lens) — Simpson (1900)
Dalliella — Simpson (1900)
Trapezoideus — Simpson (1900), Preston (1912), Simpson (1914), Preston (1915), ..., He & Zhuang (2013), Zieritz et al. (2018), Do et al. (2018), Pfeiffer et al. (2018)
— Simpson (1900), de Gregorio (1914), Simpson (1914), Haas (1969), Pfeiffer et al. (2021)
Unio — Martens (1900), Bullen (1906), Preston (1912), Simpson (1914)
Unio (Nodularia) — Dautzenberg & Fischer (1905)
Ensidens (sec. Uniandra) — Haas (1913), Thiele (1934)
Ensidens (s.s.) — Haas (1913), Haas (1969)
Contradens — Haas (1913), Haas (1914), Ortmann (1917), Haas (1924), ..., Lopes-Lima et al. (2020), Graf & Cummings (2021), Smith (2021), Bieler (2021)
Physunio (Lens) — Simpson (1914), Haas (1969)
Pseudodon (sec. Bineurus) — Simpson (1914)
Hyriopsis (s.s.) — Simpson (1914)
Schizocleithrum — Haas (1914)
Pseudodon (Bineurus) — Haas (1920), Haas (1969)
Ensidens (Uniandra) — Prashad (1932), Haas (1952), Haas (1969), Haas (1969)
Contradens (s.s.) — Modell (1942), Haas (1969)
Contradens (Sprickia) — Modell (1942), Haas (1969)
Physunio — van Benthem Jutting (1953), Brandt (1974), Graf & Cummings (2007), Sri-aroon et al. (2007), ..., Konopleva et al. (2019), Ng et al. (2020), Graf & Cummings (2021), Wu et al. (2021)
Ensidens — F.R. Woodward (1969)
Harmandia — Brandt (1974), Graf & Cummings (2007), Bogan (2010), IUCN (2012), Zieritz et al. (2018)
Uniandra — Brandt (1974), Graf (2002), Sri-aroon et al. (2007), Hoeh et al. (2009), Bogan (2010), IUCN (2012), Bogan & Do (2014), Zieritz et al. (2015)
Contortus [sic] — Araujo et al. (2017)
Lens — Zieritz et al. (2021), Jeratthitikul et al. (2021), Zieritz et al. (2021), Jeratthitikul et al. (2021), ..., Zieritz et al. (2024), Dai et al. (2024), Liu et al. (2024), Matos et al. (2024)