Unio depressa Lamarck, 1819
Lamarck, 1819. Hist. Natur. Anim. sans Vert. 6: 79, sp. 38.
Type(s): SYNTYPES MNHN_4088, Nouvelle Hollande.

Diplodon (Hyridella s.s.) cultelliformis — Simpson (1900), Simpson (1914)
Rugoshyria depressa — Iredale (1934), Iredale (1943)
Hyridella depressa — McMichael (1957), Graf (2000), Graf & Ó Foighil (2000), Graf & Ó Foighil (2000), Walker et al. (2001), ... Araujo et al. (2017), Huang et al. (2019), Lopes-Lima et al. (2020), Graf & Cummings (2021), Campbell & Lydeard (2026)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992), Graf & Cummings (2007)
Hyridella (Echyridella) depressa — Santos-Neto et al. (2016)

Unio cultelliformis Conrad, 1850
Conrad, 1850. Proc. Acad. Nat. Sci. 5: 10.
Conrad, 1854. Jour. Acad. Nat. Sci. 2(4): 296, pl. 26, fig. 6 [Unio sp.].
Type(s): HOLOTYPE ANSP_41808, Bogan River, Australia.

Diplodon (Hyridella s.s.) cultelliformis — Simpson (1900), Simpson (1914)
Rugoshyria cultelliformis — Iredale (1934), Iredale (1943)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Unio mutabilis Lea, 1859
Lea, 1859. Proc. Acad. Nat. Sci. 11: 152.
Lea, 1860. Jour. Acad. Nat. Sci. 4 [O. 7]: 248 [66], pl. 38, fig. 127.
Type(s): LECTOTYPE BMNH_1965153, Brisbane Water, East Australia.

Diplodon (Hyridella sec. Cucumaria) mutabilis — Simpson (1900), Simpson (1914)
Rugoshyria depressa — Iredale (1934), Iredale (1943)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Unio paramattensis Lea, 1862
Lea, 1862. Proc. Acad. Nat. Sci. 14: 176.
Lea, 1866. Jour. Acad. Nat. Sci. 6 [O. 11]: 60 [64], pl. 20, fig. 59.
Type(s): FIGURED SYNTYPE USNM_84405, Paramatta R., N.S.W.

Diplodon (Hyridella s.s.) cultelliformis — Simpson (1900), Simpson (1914)
— de Gregorio (1914)
Rugoshyria depressa — Iredale (1934), Iredale (1943)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Rugoshyria depressa monticola Iredale, 1934
Iredale, 1934. Austral. Zool. 8: 72, pl. 5, fig. 7a-b; pl. 6, fig. 10.
Iredale, 1943. Austral. Zool. 10: 190.
(intro'd as intra-sp. of Unio depressa Lamarck, 1819)
Type(s): HOLOTYPE (ORIG. DESIG.) AMS_61952, Kosciusko, Grosse's Plain Creek, Moonbar Run (Moonbah), New South Wales, Australia [-36.519, 148.513 ± 1 km].

Rugoshyria depressa monticola — Iredale (1934), Iredale (1943)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Rugoshyria depressa vicinalis Iredale, 1934
Iredale, 1934. Austral. Zool. 8: 72.
Iredale, 1943. Austral. Zool. 10: 190.
(intro'd as intra-sp. of Unio depressa Lamarck, 1819)
Type(s): LECTOTYPE AMS_57939 (by McMichael & Hiscock, 1958: 450), Mitchell River at Bairnsdale, Gippsland, Victoria, Australia [-37.833, 147.617 ± 10 km].

Rugoshyria depressa vicinalis — Iredale (1934), Iredale (1943)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Rugoshyria depressa bega Iredale, 1943
Iredale, 1943. Austral. Natural. 11: 91.
(intro'd as intra-sp. of Unio depressa Lamarck, 1819)
Type(s): HOLOTYPE AMS_43362, Tantawanglo River, tributary of Bega River, New South Wales, Australia [-36.742, 149.647 ± 10 km].

Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Rugoshyria depressa lowanna Iredale, 1943
Iredale, 1943. Austral. Natural. 11: 91; Abb. 1.
(intro'd as intra-sp. of Unio depressa Lamarck, 1819)
Type(s): HOLOTYPE AMS_61950, Little Nymboida River at Lowanna, near Dorrigo, New South Wales, Australia [-30.215, 152.901 ± 1 km].

Hyridella (s.s.) depressa — McMichael & Hiscock (1958), Haas (1969), B.J. Smith (1992)

Unio mutabilis Reeve, 1865
‘Lea’ Reeve, 1865. Conch. Icon. 16: pl. 24, sp. 112.
(reference to Unio mutabilis Lea, 1859)

Diplodon (Hyridella sec. Cucumaria) shuttleworthii — Simpson (1900), Simpson (1914)
Hyridella (s.s.) depressa — McMichael & Hiscock (1958)

Unio paramettensis de Gregorio, 1914
‘Lea’ de Gregorio, 1914. Il Nat. Siciliano 2: 36.
(error for Unio paramattensis Lea, 1862)