Unio contradens Lea, 1838
Lea, 1836. Synopsis Fam. Naiades: addenda. [nomen nudum]
Lea, 1838. Trans. Amer. Phil. Soc. 6 [O. 2]: 75, pl. 18, fig. 58.
Type(s): HOLOTYPE USNM_85185, [Java].

Nodularia (s.s.) contradens — Simpson (1900), Simpson (1914)
Contradens contradens — Haas (1913), Thiele (1934), van Benthem Jutting (1953), Haas (1969), Graf & Cummings (2006), ... Ng et al. (2020), Graf & Cummings (2021), Bieler (2021), Smith (2021), Sahidin et al. (2021)
— de Gregorio (1914)
Contradens (s.s.) contradens — Modell (1942), Haas (1969)
Uniandra contradens contradens — Brandt (1974)
Uniandra contradens — Graf (2002), Hoeh et al. (2009), Bogan (2010), IUCN (2012), Bogan & Do (2014), Zieritz et al. (2015)
Uniandra sp. — Sri-aroon et al. (2007)
Contortus [sic] contortus [sic] — Araujo et al. (2017)
Contradens aff. contradens sp. 1 — Bolotov et al. (2017), Bolotov et al. (2017), Bolotov et al. (2018), Konopleva et al. (2019), Konopleva et al. (2019), Huang et al. (2019), Bolotov et al. (2020)
Lens contradens — Pfeiffer et al. (2021), Jeratthitikul et al. (2021), Zieritz et al. (2021), Jeratthitikul et al. (2021), Zieritz et al. (2021), ... Jeratthitikul et al. (2024), Dai et al. (2024), Zhang et al. (2024), Dai et al. (2025), Dai et al. (2025)
Lens aff. contradens — Konopleva et al. (2023)
Lens contradens (NW Mal) — Zieritz et al. (2024)

Unio javanus Lea, 1840
Lea, 1840. Proc. Amer. Phil. Soc. 1: 285.
Lea, 1842. Trans. Amer. Phil. Soc. 8 [O. 3]: 220, pl. 18, fig. 37.
Type(s): HOLOTYPE USNM_85187, Java.

Nodularia (s.s.) contradens — Simpson (1900), Simpson (1914)
Contradens contradens — Haas (1913), van Benthem Jutting (1953), Haas (1969)
Uniandra contradens contradens — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio exilis Dunker, 1846
Dunker, 1846. Z. Malak. 3: 109.
Mousson, 1849. Land-Süßw.-Moll. Java: 92, pl. 16, fig. 3.

Nodularia (s.s.) contradens — Simpson (1900), Simpson (1914)
Contradens contradens — Haas (1913), van Benthem Jutting (1953), Haas (1969)
Uniandra contradens contradens — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio mutatus Mousson, 1849
Mousson, 1849. Land-Süßw.-Moll. Java: 92, pl. 16, figs. 1-2.

Nodularia (s.s.) contradens — Simpson (1900), Simpson (1914)
Contradens contradens — Haas (1913), van Benthem Jutting (1953), Haas (1969)
Uniandra contradens contradens — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio ascia Hanley, 1856
‘Benson, MS’ Hanley, 1856. Cat. Rec. Bivalve Shells, Suppl.: 385, pl. 23, fig. 20.
Type(s): LECTOTYPE MCZ_17046 (by R.I. Johnson, 1956: 106), Penang, India.

— Simpson (1900), Simpson (1914)
Unio ascia — Preston (1912)
Contradens ascia ascia — Haas (1924)
Ensidens (Uniandra) ascia — Prashad (1932)
Contradens ascia — Haas (1952), Haas (1969)
Uniandra contradens ascia — Brandt (1974)
Contradens contradens — Jeratthitikul et al. (2019)
Lens contradens — Pfeiffer et al. (2021)

Unio cambodiensis Lea, 1856
Lea, 1856. Proc. Acad. Nat. Sci. 8: 103.
Lea, 1857. Jour. Acad. Nat. Sci. 3 [O. 6]: 313 [33], pl. 30, fig. 28.
Type(s): HOLOTYPE USNM_84909, Tackrong R., at Korat, Cambodia.

Physunio (s.s.) cambodiensis — Simpson (1900), Simpson (1914), Haas (1919), Haas (1969)
Physunio cambodiensis — Brandt (1974), Graf & Cummings (2007), Sri-aroon et al. (2007), Bogan (2010), IUCN (2011), Zieritz et al. (2018), Do et al. (2018), Konopleva et al. (2019), Graf & Cummings (2021)
Lens contradens — Pfeiffer et al. (2021)

Unio rusticus Lea, 1856
Lea, 1856. Proc. Acad. Nat. Sci. 8: 93.
Lea, 1857. Jour. Acad. Nat. Sci. 3 [O. 6]: 294 [14], pl. 25, fig. 7.
Type(s): LECTOTYPE USNM_84082, Siam.

Nodularia (s.s.) rustica — Simpson (1900)
Contradens rusticus — Haas (1914), Ortmann (1917), Haas (1952), Haas (1969)
Nodularia (s.s.) rusticus — Simpson (1914)
Contradens (Sprickia) rusticus — Modell (1942)
Uniandra contradens rustica — Brandt (1974)
Contradens contradens — Jeratthitikul et al. (2019), Ng et al. (2020)
Lens contradens — Pfeiffer et al. (2021)

Unio tumidulus Lea, 1856
Lea, 1856. Proc. Acad. Nat. Sci. 8: 93.
Lea, 1857. Jour. Acad. Nat. Sci. 3 [O. 6]: 295 [15], pl. 25, fig. 9.
Type(s): LECTOTYPE USNM_84712, Siam.

Nodularia (s.s.) tumidula — Simpson (1900), Simpson (1914)
Ensidens (s.s.) tumidulus — Haas (1913)
Ensidens (s.s.) ingallsianus — Haas (1969)
Ensidens ingallsianus — F.R. Woodward (1969)
Uniandra contradens tumidula — Brandt (1974)
Contradens contradens — Do et al. (2018), Jeratthitikul et al. (2019), Ng et al. (2020)
Lens contradens — Pfeiffer et al. (2021)

Unio sumatrensis Lea, 1859
Lea, 1859. Proc. Acad. Nat. Sci. 11: 153.
Lea, 1860. Jour. Acad. Nat. Sci. 4 [O. 7]: 239 [57], pl. 34, fig. 118.
(homonym of Unio sumatrensis Dunker, 1852; renamed Margaron (Unio) dimotus Lea, 1870)
Type(s): HOLOTYPE USNM_84059, Sumatra.

Nodularia (s.s.) dimota — Simpson (1900), Simpson (1914)
Unio sumatrensis — Bullen (1906)
Contradens dimotus dimotus — Haas (1913)
Contradens ascia — Haas (1969)
Uniandra contradens dimotus — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)
Contradens contradens — Bieler (2021)

Unio mederianus Küster, 1861
‘Mousson’ Küster, 1861. Conchyl. Cab. 9(2): 242, pl. 80, fig. 7.

Nodularia (s.s.) contradens — Simpson (1900), Simpson (1914)
Contradens contradens — Haas (1913), van Benthem Jutting (1953), Haas (1969)
Uniandra contradens contradens — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio paivanus Morelet, 1865
Morelet, 1865. J. de Conch. 13: 227.
Type(s): HOLOTYPE BMNH_93-2-4-1738, Siam.

Nodularia (s.s.) rustica — Simpson (1900)
Contradens rusticus — Haas (1914), Haas (1969)
Nodularia (s.s.) rusticus — Simpson (1914)
Uniandra contradens rustica — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio asperulus Lea, 1866
Lea, 1866. Proc. Acad. Nat. Sci. 18: 133.
Lea, 1868. Jour. Acad. Nat. Sci. 6 [O. 12]: 280, pl. 38, fig. 94.
Type(s): HOLOTYPE USNM_84078, Siam.

Nodularia (s.s.) asperula — Simpson (1900), Simpson (1914)
Ensidens (sec. Uniandra) asperulus — Haas (1913)
Ensidens (Uniandra) asperulus — Prashad (1932), Haas (1952), Haas (1969)
Uniandra contradens tumidula — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Margaron (Unio) dimotus Lea, 1870
Lea, 1870. Synopsis Fam. Naiades: 30.
(new name for Unio sumatrensis Lea, 1859)

Nodularia (s.s.) dimota — Simpson (1900), Simpson (1914)
Contradens dimotus dimotus — Haas (1913)
Contradens ascia dimotus — Haas (1924), van Benthem Jutting (1953), Marwoto (1987)
Contradens ascia — Haas (1969)
Uniandra contradens dimotus — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)
Contradens contradens — Bieler (2021)

Unio dautzenbergi Morlet, 1889
Morlet, 1889. J. de Conch. 37: 163, 190, pl. 8, fig. 5.

Nodularia (s.s.) dautzenbergi — Simpson (1900), Simpson (1914)
Unio (Nodularia) dautzenbergi — Dautzenberg & Fischer (1905)
Contradens dautzenbergi — Haas (1914), Haas (1969)
Uniandra contradens rustica — Brandt (1974)
Contradens contradens — Do et al. (2018), Ng et al. (2020)
Lens contradens — Pfeiffer et al. (2021)

Unio semidecoratus Morlet, 1889
Morlet, 1889. J. de Conch. 37: 164, 192, pl. 8, fig. 4.

Nodularia (s.s.) semidecorata — Simpson (1900)
Ensidens (sec. Uniandra) inaequalis — Haas (1913)
Nodularia (s.s.) inaequalis — Simpson (1914)
Ensidens (Uniandra) inaequalis — Haas (1969)
Uniandra contradens tumidula — Brandt (1974)
Contradens contradens — Do et al. (2018)
Lens contradens — Pfeiffer et al. (2021)

Microcondylaea bicristata Strubell, 1897
Strubell, 1897. Nachr. Bl. Dtsch. Malak. Ges. 29: 9.

Contradens hageni — Haas (1913)
Pseudodon (sec. Bineurus) bicristatus — Simpson (1914)
Pseudodon (Bineurus) bicristatus — Haas (1920)
Pseudodon (Bineurus) hageni — Haas (1969)
Uniandra contradens dimotus — Brandt (1974)

Unio hageni Strubell, 1897
Strubell, 1897. Nachr. Bl. Dtsch. Malak. Ges. 29: 10.
Type(s): TYPE SMF_3603, S. Sumatra.

— Simpson (1900)
Contradens hageni — Haas (1913), Ortmann (1917), Haas (1969)
Nodularia (s.s.) dimota — Simpson (1914)
Uniandra contradens dimotus — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio verbecki Martens, 1897
‘Bött.’ Martens, 1897. Zool. Erg. Nied. Ost. Ind. 4: 89, pl. 5, figs. 1-2, 4-5.

Nodularia (s.s.) verbecki — Simpson (1900), Simpson (1914)
Contradens verbeeki [sic] — Haas (1914), Haas (1969)
Contradens verbecki — Ortmann (1917)
Contradens (Sprickia) verbeeki [sic] — Modell (1942), Haas (1969)
Uniandra contradens dimotus — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Trapezoideus peninsularis Simpson, 1900
‘Lea’ Reeve, 1865. Conch. Icon. 16: pl. 28, sp. 142 [as ‘Unio sumatrensis’].
Simpson, 1900. Proc. U.S. Nat. Mus. 22: 859, footnote.
Simpson, 1914. Descr. Cat. Naiades: 1186.
Type(s): TYPE BMNH_1964159, Sumatra.

Trapezoideus peninsularis — Simpson (1900), Simpson (1914), Zieritz et al. (2018)
— Haas (1969)
Trapezoideus peninsularius [sic] — Graf & Cummings (2007), Bogan (2010)
Contradens peninsularis — Konopleva et al. (2019), Konopleva et al. (2019), Graf & Cummings (2021)
Lens contradens — Pfeiffer et al. (2021)

Unio laticeps Martens, 1900
Martens, 1900. Nachr. Bl. Dtsch. Malak. Ges. 32: 15.
Type(s): TYPES ZMB_51796, Aus dem Danau Baru, Indragiri, O. Sumatra.

Unio laticeps — Martens (1900)
Contradens semmelincki [sic] laticeps — Haas (1914)
Nodularia (s.s.) laticeps — Simpson (1914)
Contradens semmelincki [sic] — Haas (1969)
Lens contradens — Pfeiffer et al. (2021)

Unio pajakomboensis Bullen, 1906
Bullen, 1906. Proc. Malac. Soc. London 7: 15, pl. 2, figs. 9-11.
Type(s): HOLOTYPE BMNH_1906-1-16-52, Pajakombo, Sumatra.

Unio pajakomboensis — Bullen (1906), Simpson (1914)
Schizocleithrum pajacomboënse [sic] — Haas (1914)
Contradens hageni — Haas (1969)
Uniandra contradens dimotus — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Unio verbeeki Haas, 1914
‘von Martens’ of Authors.
‘(Boettger) v. Martens’ Haas, 1914. Conch. Cab. 9 (pt. 2, h. 49): 198.
Modell, 1942. Arch. Moll. 74(5/6): 189.
‘Martens’ Haas, 1969. Das Tierreich 88: 101.
‘Martens’ Haas, 1969. Treatise on Invert. Paleo: N420.
‘(Martens)’ Brandt, 1974. Arch. Moll. 105: 289.
Millard, 2001. Class. Moll. (3): 1064.
(error for Unio verbecki Martens, 1897)

Lens contradens — Pfeiffer et al. (2021)

Unio thaiensis Habe, 1964
Habe, 1964. Nature & Life in Southeast Asia 3: 62, pl. ?, figs. 3-4.

Uniandra contradens rustica — Brandt (1974)
Lens contradens — Pfeiffer et al. (2021)

Uniandra contradens rusticoides Brandt, 1974
Brandt, 1974. Arch. Moll. 105: 290, pl. 24, fig. 50.
(intro'd as intra-sp. of Unio contradens Lea, 1838)
Type(s): HOLOTYPE SMF_220845, Thailand: Klong Min near Chandi; Chawang Distr.; Prov. Nakon Sritammarat.

Uniandra contradens rusticoides — Brandt (1974)
Contradens contradens — Jeratthitikul et al. (2019)
Lens contradens — Pfeiffer et al. (2021)

Trapezoideus peninsularius Graf & Cummings, 2007
‘Simpson’ of Authors.
Graf & Cummings, 2007. J. Moll. Studies 73: 312.
Bogan, 2010. FADA: [web].
(error for Trapezoideus peninsularis Simpson, 1900)

Lens contradens — Pfeiffer et al. (2021)

Contradens dimotus var. lugens of Authors, unknown year
Prashad of Authors.
(misidentified reference to Unio lugens Drouët & Chaper, 1892)

Uniandra contradens dimotus — Brandt (1974)

Unio mutatus form curvatus Mousson, 1849
Mousson, 1849. Land-Süßw.-Moll. Java: 92 pl. 16, fig. 2. [infra-subsp.]
(homonym of Unio bonelli var. curvata Rossmässler, 1842; intro'd as intra-sp. of Unio mutatus Mousson, 1849)

Contradens contradens — van Benthem Jutting (1953)

Unio mutatus form inflatus Mousson, 1849
Mousson, 1849. Land-Süßw.-Moll. Java: 92. [infra-subsp.]
(homonym of Unio inflatus Studer, 1820; intro'd as intra-sp. of Unio mutatus Mousson, 1849)

Contradens contradens — van Benthem Jutting (1953)

Unio mutatus form obscurus Mousson, 1849
Mousson, 1849. Land-Süßw.-Moll. Java: 92, pl. 16, fig. 1. [infra-subsp.]
(homonym of Unio obscurus Lea, 1838; intro'd as intra-sp. of Unio mutatus Mousson, 1849)

Contradens contradens — van Benthem Jutting (1953)

Unio sumatrensis Reeve, 1865
‘Lea’ Reeve, 1865. Conch. Icon. 16: pl. 28, sp. 142.
(reference to Unio sumatrensis Lea, 1859)

Trapezoideus peninsularis — Simpson (1900), Simpson (1914)

Unio paivaeanus Morelet, 1875
Morelet, 1875. Séries Conch. 4: 353 [as ‘paivæanus’].
Morlet, 1889. J. de Conch. 37: 164 [as ‘paivæanus’].
(error for Unio paivanus Morelet, 1865)

Unio cambodgensis Fischer, 1891
‘Lea’ Fischer, 1891. Bull. Soc. Hist. Nat. Autun 4: 224.
(error for Unio cambodiensis Lea, 1856)

Unio hagnei Simpson, 1900
‘Strubell’ Simpson, 1900. Proc. U.S. Nat. Mus. 22: 862.
(error for Unio hageni Strubell, 1897)

Schizocleithrum pajacomboense Haas, 1914
Haas, 1914. Conch. Cab. 9 (pt. 2, h. 49): 203 [as ‘pajacomboënse’].
(error for Unio pajakomboensis Bullen, 1906)

Trapezoideus pulcher Haas, 1952
‘Taaparone-Canefri’ [sic] Haas, 1952. Bull. Nat. Hist. Siam Soc. 15(1): 23.
(misidentified reference to Unio pulcher Tapparone Canefri, 1889)
Type(s): SPECIMENS FMNH_33020, Klong Klung River, Kam Peng Pet Prov., NW Siam.

Trapezoideus exolescens exolescens — Brandt (1974)
Trapezoideus exolescens — He & Zhuang (2013)

Contortus contortus Araujo et al., 2017
Araujo et al., 2017. Zool. J. Linn. Soc. 179(2): 280.
(error for Unio contradens Lea, 1838)

Lens contradens — Pfeiffer et al. (2021)