species Unio elongatulus Pfeiffer, 1825: synonymy

Unio elongatula C. Pfeiffer, 1825

C. Pfeiffer, 1825. Natur. Deutsch. Land Sussw. Moll. 2: 35, pl. 8, figs. 5-6.
NEOTYPE MZUF_BC_53138, Vipava (Vipacco) River, Savogna d’Isonzo, Gorizia, Friuli-Venezia Giulia, Italy.

Unio (sec. Lymnium) elongatulus — Simpson (1900)
Unio (Groupe des Elongatulusiana) elongatulus — Caziot (1907)
Unio (sec. Lymnium) (Group U. pictorum) elongatulus — Simpson (1914)
Unio elongatulus elongatulus — Haas (1940), Haas (1969), Fauna Europaea (2012)
Unio elongatus [sic] — Haas (1952)
Unio elongatulus — Van Damme (1984), Mandahl-Barth (1988), Dhora (2009), Bogan (2010), Prie et al. (2012), ... Wang et al. (2025), Nagel (2025), Campbell & Lydeard (2026), Wu et al. (2026), Wu et al. (2026)
Unio mancus — Nagel et al. (1998), Araujo et al. (2005), Graf & Cummings (2007), Graf & Cummings (2011), IUCN (2014)
Unio cf. elongatulus — Lopes-Lima et al. (2017)

Unio elongatus ‘Pfeiffer’ of Authors

(error for Unio elongatula C. Pfeiffer, 1825)
‘Pfeiffer’ of Authors.
Lea, 1836. Synopsis Fam. Naiades: 37.
Lea, 1838. Synopsis Fam. Naiades: 24.
Lea, 1852. Synopsis Fam. Naiades: 37.
Adams & Adams, 1857. Gen. Rec. Moll. 2(31-32): 491.
Haas, 1952. Nautilus 65(4): 118.
Bogan, 1993. Amer. Zool. 33: 602.

Unio glaucinus Porro, 1838

Porro, 1838. Malacol. Prov. Comasca: 115.

Unio (sec. Lymnium) batavus — Simpson (1900)
Unio (sec. Lymnium) (Group U. littoralis) batavus — Simpson (1914)
Unio elongatulus glaucinus — Haas (1940), Haas (1969), Fauna Europaea (2012)
Unio (s.s.) mancus glaucinus — Falkner et al. (2001)
Unio mancus — Araujo et al. (2005), IUCN (2014), Araujo et al. (2018)
Unio cf. elongatulus — Lopes-Lima et al. (2017)
Unio elongatulus — Marrone et al. (2019)

Potomida sicula Swainson, 1840

Swainson, 1840. Treat. Malacol.: 282, fig. 58.
POSSIBLE SYNTYPE BMNH_1907-10-28-255, Lake Leontini, Sicily.

Unio (sec. Lymnium) pictorum — Simpson (1900)
Unio (sec. Lymnium) (Group U. pictorum) pictorum — Simpson (1914)
Unio pictorum — He & Zhuang (2013)

Unio corrosus Villa, 1841

Villa, 1841. Dispos. Syst. Conchyl.: 61.
SYNTYPES SMF 17250, Lago di Pusiano, Italy.

Unio crassus — Germain (1931)
Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio pallens Rossmässler, 1842

‘Parr.’ Rossmässler, 1842. Icon. Land- und Süssw.-Moll. 2 (5): 13, pl. 54, fig. 740.
LECTOTYPE SMF 4497 (by Zilch, 1967: 74), Dalmatien.

Unio (sec. Lymnium) turtoni — Simpson (1900)
Unio (sec. Lymnium) (Group U. pictorum) turtonii — Simpson (1914)
Unio elongatulus pallens — Haas (1940), Haas (1969), Fauna Europaea (2012)
Unio mancus pallens — Lopes-Lima et al. (2017)
Unio elongatulus — Araujo et al. (2018), Marrone et al. (2019), Nagel (2025)

Unio sandrii Rossmässler, 1844

‘Villa’ Rossmässler, 1844. Icon. Land- und Süssw.-Moll. 2 (6): 26, pl. 56, fig. 748-749.
LECTOTYPE SMF 10714 (by Zilch, 1967: 75), “Dalmatien”.

Unio (sec. Lymnium) batavus — Simpson (1900)
Unio (sec. Lymnium) (Group U. littoralis) batavus — Simpson (1914)
Unio elongatulus sandrii — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio sandrii var. sericatus Rossmässler, 1844

(intro'd as intra-sp. of Unio sandrii Rossmässler, 1844)
‘Parreyss’ Rossmässler, 1844. Icon. Land- und Süssw.-Moll. 2 (6): 27, pl. 56, fig. 750.
LECTOTYPE SMF 10757 (by Zilch, 1967: 75), Dalmatien.

Unio elongatulus sandrii — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio pictorum var. parva Stabile, 1845

(homonym of Unio parvus Barnes, 1823; renamed Unio eucallistellus Bourguignat, 1883)
Stabile, 1845. Faun. Lug.: 61, f. 73.

Unio elongatulus — Marrone et al. (2019)

Unio spinellii Spinelli, 1851

‘Villa’ Spinelli, 1851. Cat. Moll. Terr. Fluv. Prov. Brescia: 20, figs. 7-8.

Unio (sec. Lymnium) batavus — Simpson (1900)
Unio (sec. Lymnium) (Group U. littoralis) batavus — Simpson (1914)
Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio viridiflavus Küster, 1854

Küster, 1854. Conchyl. Cab. 9(2): 96, pl. 26, figs. 2-3.

Unio (sec. Lymnium) pictorum — Simpson (1900)
Unio (sec. Lymnium) (Group U. pictorum) pictorum — Simpson (1914)
Unio elongatulus pallens — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio petterianus Küster, 1854

Küster, 1854. Conchyl. Cab. 9(2): 97, pl. 26, fig. 4.

Unio (sec. Lymnium) batavus — Simpson (1900)
Unio (sec. Lymnium) (Group U. littoralis) batavus — Simpson (1914)
Unio elongatulus pallens — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio petrovichii Küster, 1854

Küster, 1854. Conchyl. Cab. 9(2): 98, pl. 26, figs. 5-6; pl. 27, fig. 1.

Unio (sec. Lymnium) pictorum — Simpson (1900)
Unio (sec. Lymnium) (Group U. pictorum) pictorum — Simpson (1914)
Unio elongatulus pallens — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio requienii var. vulgaris Stabile, 1859

(intro'd as intra-sp. of Unio requienii Michaud, 1831)
Stabile, 1859. Atti soc. geol. Milano 1: 170, 184, sp. 49.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio requienii var. oriliensis Stabile, 1859

(intro'd as intra-sp. of Unio requienii Michaud, 1831)
Stabile, 1859. Atti soc. geol. Milano 1: 170, 184, sp. 50.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio requienii var. blauneri Stabile, 1859

(intro'd as intra-sp. of Unio requienii Michaud, 1831)
‘Shuttleworth’ Stabile, 1859. Atti soc. geol. Milano 1: 170, 185, sp. 51.

Unio blauneri — Haas (1924)
Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio villae Issel, 1872

Issel, 1872. Mem. Soc. Ital. Sci. Nat. 2: 35.

Unio villæ — Rochebrune (1903)
Unio villae — Germain (1931)
Unio elongatulus glaucinus — Haas (1940), Haas (1969)

Unio fiscallianus Kobelt, 1873

‘Kleciach’ Kobelt, 1873. Malak. Blatt. 20: 92, text fig.
LECTOTYPE SMF 4393 (by Zilch, 1967: 71), bei dem Städtchen Glavina, Croatia.

Unio (sec. Lymnium) platyrhynchus — Simpson (1900)
Unio (sec. Lymnium) (Group U. pictorum) platyrhynchus — Simpson (1914)
Unio elongatulus fiscallianus — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio nitidosus Drouët, 1879

Drouët, 1879. J. de Conch. 27: 140.

Unio elongatulus pallens — Haas (1940), Haas (1969)
Unio (s.s.) mancus kruperi — Bank (2006)

Unio ceratinus Drouët, 1879

Drouët, 1879. J. de Conch. 27: 328.

Unio elongatulus sandrii — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio dalmaticus Drouët, 1879

Drouët, 1879. J. de Conch. 27: 141.

Unio elongatulus sandrii — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio robustus ‘Villa, in sched.’ Drouët, 1879

(renamed Unio larius Drouët, 1883; homonym of Unio robustus J. de C. Sowerby, 1840)
‘Villa, in sched.’ Drouët, 1879. J. de Conch. 27: 141.

Unio elongatulus glaucinus — Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio kleciaki Drouët, 1879

Drouët, 1879. J. de Conch. 27: 328.

Unio elongatulus — Marrone et al. (2019)

Unio succineus Drouët, 1881

Drouët, 1881. J. de Conch. 29: 245.

Unio elongatulus sandrii — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio decipiens Drouët, 1881

Drouët, 1881. J. de Conch. 29: 23.

Unio elongatulus decipiens — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio brachyrhynchus Drouët, 1881

Drouët, 1881. J. de Conch. 29: 246.
SYNTYPE SMF 11060, Mincio River, Italy.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio veillanensis Locard, 1882

‘H. Blanc’ Locard, 1882. Prodr. Malac. Franç. 1: 292, 361.
‘H. Blanc’ Locard, 1889. Contr. Faune Malacol. Franc. 13: 154 [48].
‘H. Blanc’ Locard, 1893. Coqu. Eau Douce Saumâtre France: 185.
LECTOTYPE MNHN_22601 (by Graf, 2011: 511), Montpellier.

Unio villae — Germain (1931)
Unio elongatulus requienii — Haas (1940), Haas (1969)
Unio mancus requienii — Prie (2012)

Unio opisodartos Adami, 1882

Adami, 1882. Bull. Soc. Malac. Ital. 8: 134, pl. 0, figs. 9-10.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio stephaninii Adami, 1882

Adami, 1882. Bull. Soc. Malac. Ital. 8: 129, pl. 0, figs. 1-2.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio gurkensis Ziegler in Bourguignat, 1883

Ziegler in Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 21.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio larius Drouët, 1883

(new name for Unio robustus ‘Villa, in sched.’ Drouët, 1879)
Drouët, 1883. Unionidae de l’Italie: 26.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio subcylindricus ‘Pini, in sched.’ Drouët, 1883

‘Pini, in sched.’ Drouët, 1883. Unionidae de l’Italie: 34.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio fluminalis Drouët, 1883

Kobelt, 1876. Icon. Land- und Süssw.-Moll. 4: 63, pl. 117, fig. 1148 [as ‘U. requieni’].
Drouët, 1883. Unionidae de l’Italie: 35.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio gredleri Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 68.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio minusculus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 77.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio benacinus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 74.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio siliquatus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 66.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio nitidus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 57.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio delpretei Bourguignat, 1883

Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 23.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio eucallistellus Bourguignat, 1883

(new name for Unio pictorum var. parva Stabile, 1845)
Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 48.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio callichrous Letourneux in Bourguignat, 1883

Letourneux in Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 49.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)

Unio padanus H. Blanc in Bourguignat, 1883

H. Blanc in Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 57.

Unio requieni — Germain (1931)
Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio mancus requienii — Prie (2012)
Unio elongatulus — Marrone et al. (2019)

Unio strobeli Uzielli in Bourguignat, 1883

Uzielli in Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 58.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio pedemontanus Bourguignat, 1883

Kobelt, 1876. Icon. Land- und Süssw.-Moll. 4: 63, pl. 117, fig. 1148 [as ‘U. requienii].
Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 60.
SYNTYPE SMF 10739, ditch near Mantua, Italy.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Nagel (2025)

Unio sebinensis Uzielli in Bourguignat, 1883

Uzielli in Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 13.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio verbanicus Letourneux in Bourguignat, 1883

Letourneux in Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 18.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio longobardus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 54.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio brianteus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 35.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio idrinus Drouët, 1883

Drouët, 1883. Unionidae de l’Italie: 42.

Unio elongatulus — Marrone et al. (2019)

Unio cusianus Pini, 1884

Pini, 1884. Atti Soc. Ital. Sci. Nat. 27: 82, text fig.

Unio elongatulus glaucinus — Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio rusticus Pini, 1884

(homonym of Unio rusticus Lea, 1856)
Pini, 1884. Atti Soc. Ital. Sci. Nat. 27: 80, text figs.

Unio elongatulus — Marrone et al. (2019)

Unio athesinus Adami, 1886

Adami, 1886. Bull. Soc. Malac. Ital. 11: 236, figs. 16-17.
Kobelt, 1886. Icon. Land- und Süssw.-Moll. 2: 49, pl. 57, fig. 299.
LECTOTYPE SMF 10725 (by Zilch, 1967: 72), Italy.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio ruffonii Adami, 1886

Adami, 1886. Bull. Soc. Malac. Ital. 11: 248, figs. 26-27.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio bourguignatianus Adami, 1886

(homonym of Unio bourguignatianus Lea, 1863; renamed Unio magistri Westerlund, 1890)
Adami, 1886. Bull. Soc. Malac. Ital. 11: 234, figs. 13-14.

Unio elongatulus — Marrone et al. (2019)

Unio tommasii Adami, 1886

Adami, 1886. Bull. Soc. Malac. Ital. 11: 241, figs. 20-21.

Unio elongatulus — Marrone et al. (2019)

Unio gredleri Adami, 1886

(homonym of Unio gredleri Drouët, 1883; renamed Unio humerosus Westerlund, 1890)
Adami, 1886. Bull. Soc. Malac. Ital. 11: 245, fig. 22.

Unio piccinellii Adami, 1886

Adami, 1886. Bull. Soc. Malac. Ital. 11: 239, figs. 18-19.

Unio elongatulus — Marrone et al. (2019)

Unio cristophori Adami, 1886

Adami, 1886. Bull. Soc. Malac. Ital. 11: 242, figs. 24-25.

Unio elongatulus — Marrone et al. (2019)

Unio christophori ‘Adam’ of Authors

(error for Unio cristophori Adami, 1886)
‘Adam’ of Authors.
Servain, 1888. Bull. Soc. Malac. France 5: 319.
Westerlund, 1890. Fauna Paläarct. Binnenconch. 2(7): 168.

Unio lijacensis Kobelt, 1890

Kobelt, 1890. Icon. Land- und Süssw.-Moll. 4: 94, pl. 117, figs. 706, 708.
LECTOTYPE SMF 10738 (by Zilch, 1967: 68), Lijak River, a tributary of the Isonzo, Slovenia.

Unio elongatulus elongatulus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio lijacensis var. gallensteini Kobelt, 1890

(intro'd as intra-sp. of Unio lijacensis Kobelt, 1890)
Kobelt, 1890. Icon. Land- und Süssw.-Moll. 4: 94, pl. 117, fig. 707.
LECTOTYPE SMF 4395 (by Zilch, 1967: 68), “Torrente Versa im Isonzogebiet”, Italy.

Unio elongatulus elongatulus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio humerosus Westerlund, 1890

(homonym of Unio humerosus Lea, 1868; new name for Unio gredleri Adami, 1886)
Westerlund, 1890. Fauna Paläarct. Binnenconch. 2(7): 136.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio magistri Westerlund, 1890

(new name for Unio bourguignatianus Adami, 1886)
Westerlund, 1890. Fauna Paläarct. Binnenconch. 2(7): 132.

Unio veilanensis ‘Blanc’ of Authors

(error for Unio veillanensis Locard, 1882)
‘Blanc’ of Authors.
Locard, 1893. Coqu. Eau Douce Saumâtre France: 185.
Germain, 1931. Faune de France 22: 735.

Unio limosus var. costanus Tiesenhausen in Gredler, 1894

(intro'd as intra-sp. of Unio limosus Nilsson, 1822)
Tiesenhausen in Gredler, 1894. Slebstvelag der Lehranstalt 8: 35.
SYNTYPE SMF 10789, Lago della Costa, near Pergine, Italy.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio limosus var. arcensis Gredler, 1894

(intro'd as intra-sp. of Unio limosus Nilsson, 1822)
Gredler, 1894. Slebstvelag der Lehranstalt 8: ??.

Unio elongatulus — Marrone et al. (2019)

Unio humerosus var. monticellensis Gredler, 1894

(intro'd as intra-sp. of Unio humerosus Westerlund, 1890)
Gredler, 1894. Slebstvelag der Lehranstalt 8: ??.

Unio elongatulus — Marrone et al. (2019)

Unio athesinus var. trilacensis Gredler, 1894

(intro'd as intra-sp. of Unio athesinus Adami, 1886)
Gredler, 1894. Slebstvelag der Lehranstalt 8: ??.

Unio elongatulus — Marrone et al. (2019)

Unio quellenneci Drouët, 1895

Drouët, 1895. J. de Conch. 43: 26, sp. 101.

Unio elongatulus quelleneci [sic] — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio (s.s.) mancus kruperi — Bank (2006)

Unio copaisanus ‘Clessin, in sched.’ Drouët, 1895

‘Clessin, in sched.’ Drouët, 1895. J. de Conch. 43: 27, sp. 102.

Unio elongatulus quelleneci [sic] — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio (s.s.) mancus kruperi — Bank (2006)

Unio directus Drouët, 1895

Drouët, 1895. J. de Conch. 43: 30, sp. 106.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio palustris Drouët, 1895

Drouët, 1895. J. de Conch. 43: 31, sp. 107.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019)

Unio thermalis ‘Monterosato, in sched.’ Drouët, 1895

‘Monterosato, in sched.’ Drouët, 1895. J. de Conch. 43: 29, sp. 105.

Unio elongatulus rousii — Haas (1940)
Unio elongatulus — Marrone et al. (2019)

Unio segregatus ‘Monterosato, in sched.’ Drouët, 1895

‘Monterosato, in sched.’ Drouët, 1895. J. de Conch. 43: 29, sp. 104.

Unio elongatulus — Marrone et al. (2019)

Unio istrianus Stossich, 1899

Stossich, 1899. Boll. Soc. adriatica scienze nat. Trieste 19: 50, text fig.

Unio elongatulus — Marrone et al. (2019)

Unio morlachicus Kobelt, 1915

Kobelt, 1915. Icon. Land- und Süssw.-Moll. 20: 11, pl. 544, figs. 2774-2776.
LECTOTYPE SMF 10799 (by Zilch, 1967: 75), Dalmatien.

Unio elongatulus sandrii — Haas (1940)
Unio elongatulus pallens — Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio humerosus var. elongata Kobelt, 1915

(homonym of Unio elongata Lamarck, 1819; intro'd as intra-sp. of Unio humerosus Westerlund, 1890)
Kobelt, 1915. Icon. Land- und Süssw.-Moll. 20: 9, pl. 542, fig. 2770.
HOLOTYPE SMF 10783, Lago di Caldonazzo, Trentino, Italy.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio humerosus var. roboretana Kobelt, 1915

(intro'd as intra-sp. of Unio humerosus Westerlund, 1890)
Kobelt, 1915. Icon. Land- und Süssw.-Moll. 20: 8, pl. 542, fig. 2769.
HOLOTYPE SMF 10786, Adige River, Rovereto, Italy.

Unio elongatulus glaucinus — Haas (1940), Haas (1969)
Unio elongatulus — Marrone et al. (2019), Nagel (2025)

Unio elongatulus Rossmässler, 1835

(reference to Unio elongatula C. Pfeiffer, 1825)
‘Mühlf.’ Rossmässler, 1835. Icon. Land- und Süssw.-Moll. 1 (2): 23, pl. 9, fig. 132.
Rossmässler, 1844. Icon. Land- und Süssw.-Moll. 2 (6): 27, pl. 56, fig. 751.

Unio (sec. Lymnium) elongatulus — Simpson (1900)
Unio elongatulus — Rochebrune (1903), Haas (1924)
Unio mancus var. elongatulus — Germain (1931)

Unio vindiflavus Lea, 1852

(error for Unio viridiflavus Küster, 1854)
‘Küster’ Lea, 1852. Synopsis Fam. Naiades: 37.
‘Küster’ Lea, 1870. Synopsis Fam. Naiades: 59.

Unio ovalis var. intercedens Gredler, 1860

(homonym of Unio intercedens Lea, 1857)
‘Moll. Tirol II’ Gredler, 1860. unknown publication: 58. [nomen nudum]

Unio elongatulus — Marrone et al. (2019)

Unio veillanicus Bourguignat, 1883

(error for Unio veillanensis Locard, 1882)
‘H. Blanc’ Bourguignat, 1883. Aperçu Unionid. Pénins. Ital.: 32.

Unio elongatulus — Marrone et al. (2019)

Unio cristoforii Locard, 1889

(error for Unio cristophori Adami, 1886)
‘Adami’ Locard, 1889. Contr. Faune Malacol. Franc. 13: 153 [47].

Unio palleus Locard, 1889

(error for Unio pallens Rossmässler, 1842)
‘Parreys’ Locard, 1889. Contr. Faune Malacol. Franc. 13: 156 [50].

Unio klecaki Westerlund, 1890

(error for Unio kleciaki Drouët, 1879)
‘Drouët’ Westerlund, 1890. Fauna Paläarct. Binnenconch. 2(7): 114.

Unio quelleneci Kobelt, 1896

(error for Unio quellenneci Drouët, 1895)
‘Drouët’ Kobelt, 1896. Icon. Land- und Süssw.-Moll. 7: 100.
‘Drouet’ Haas, 1940. Zool. Ser. Field Mus. Nat. Hist. 24: 125.

Unio quellencci Kobelt, 1896

(error for Unio quellenneci Drouët, 1895)
‘Drouët’ Kobelt, 1896. Icon. Land- und Süssw.-Moll. 7: 100.

Unio mancus var. elongatus Germain, 1931

(error for Unio elongatulus Rossmässler, 1835)
‘Mühlfeld’ Germain, 1931. Faune de France 22: 725.

Unio sabinensis Haas, 1940

(error for Unio sebinensis Uzielli in Bourguignat, 1883)
Haas, 1940. Zool. Ser. Field Mus. Nat. Hist. 24: 127.