species Yaukthwa dalliana (Frierson, 1913): synonymy

Parreysia dalliana Frierson, 1913

Frierson, 1913. Nautilus 26: 142.
‘Gould’ Haas, 1919. Conch. Cab. 9 (pt. 2, h. 51): pl. 32, figs. 3-4.
Type(s): LECTOTYPE SMF_13699B, Lashio Fl. Lashio nordl Shan Staaten.

Parreysia (s.s.) dalliana — Preston (1915)
Trapezoideus dallianus — Haas (1919), Prashad (1922), Srinivasa Rao (1928)
Trapezoideus foliaceus — Haas (1969)
Trapezoideus exolescens — He & Zhuang (2013)
Yaukthwa cf. dalliana — Konopleva et al. (2019), Bolotov et al. (2019), Konopleva et al. (2019), Zieritz et al. (2020)
Yaukthwa dalliana — Bolotov et al. (2020), Pfeiffer et al. (2021), Graf & Cummings (2021), Bolotov et al. (2022), Campbell & Lydeard (2026)

Unio foliaceus Martens, 1899

‘Gould’ Martens, 1899. Arch. Naturg. 65: 42.
(misidentified reference to Unio foliaceus Gould, 1843)

Trapezoideus dallianus — Haas (1919), Prashad (1922)

Trapezoideus foliaceus Haas, 1919

‘Gould’ Haas, 1919. Conch. Cab. 9 (pt. 2, h. 51): pl. 32, figs. 3-4.
(misidentified reference to Unio foliaceus Gould, 1843)