species Lens contradens (Lea, 1838): synonymy

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)
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), ... Chen et al. (2025), Chen et al. (2025), Campbell & Lydeard (2026), Wu et al. (2026), Zieritz et al. (2026)
Lens aff. contradens — Konopleva et al. (2023)
Lens contradens (NW Mal) — Zieritz et al. (2024)
Lens cf. contradens — Zieritz et al. (2026)

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. Zeitschr. f. Malakozool. 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. Illustr. Descr. Cat. Rec. Bivalve Shells: 385, pl. 23, fig. 20.
Type(s): LECTOTYPE MCZ_17046 (by R.I. Johnson, 1956: 106), Penang, India.

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.
(renamed Margaron (Unio) dimotus Lea, 1870; homonym of Unio sumatrensis Dunker, 1852)
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.

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)
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 ‘von Martens’ of Authors

‘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 1: 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 ‘Simpson’ of Authors

‘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 Prashad of Authors

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.]
(intro'd as intra-sp. of Unio mutatus Mousson, 1849; homonym of Unio bonelli var. curvata Rossmässler, 1842)

Contradens contradens — van Benthem Jutting (1953)

Unio mutatus form inflatus Mousson, 1849

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

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)