Unio depauperata Hutton, 1883

Brook, Fred J., Kennedy, Martyn, King, Tania M., Ridden, Johnathon, Shaw, Matthew D. & Spencer, Hamish G., 2020, Catalogue of New Zealand land, freshwater and estuarine molluscan taxa named by Frederick Wollaston Hutton between 1879 and 1904, Zootaxa 4865 (1), pp. 1-73 : 11

Unio depauperata Hutton, 1883

Pl. 1, fig. A

Hutton, 1883 . New Zealand Journal of Science, 1: 478.

Type material. Lectotype, CMNZ M670 (pair of dry valves), and paralectotypes, NMNZ M.644 (pair of dry valves), NMNZ M.125068 [ex M.644] (pair of dry valves). Lectotype fixed by inference of holotype ( ICZN Art. 74.6) by Allan (1938: 182). Lectotype designation of Dell (1953: 231) preceded by that of Allan (1938: 182).

Label details. CMNZ M670—‘ D. depauperata, L. Takapuna , Type’; NMNZ M.644— ‘U. depauperatus Hutton n.s., Lake Takapuna, Auckland’.

CMNZ molluscan catalogue details. ‘ Diplodon menziesi depauperatus ( Hutton ), Lake Takapuna, Holotype, (2 valves), (ZS 968c—old number)’.

Type locality. ‘Lake Takapuna, Auckland’ [= Lake Pupuke] ( Hutton 1883h: 478 , 1884d: 216).

Previous illustrations of type material. Dell (1953: pl. 17, fig. 10— paralectotype); Marshall et al. (2014: fig. 4A, C—paralectotype).

Remarks. Hutton submitted a description of Unio depauperata to the Transactions and Proceedings of the New Zealand Institute issue for 1883, but publication was delayed until May 1884 ( Hutton 1884d: 216 ), and was preempted by a brief description of Unis [sic] depauperata in an account of a meeting of the Philosophical Institute of Canterbury ( Hutton 1883h: 478 ). Hutton (1884d) noted that this taxon was “perhaps an impoverished form of U. zelebori [Dunker, 1866: see Marshall & Fenwick 2006], but too distinct to be passed over”. It has been treated as a subspecies of the morphologically variable species Unio menziesii Gray (e.g., by Simpson 1900: 890; 1914: 1292; Suter 1913: 941; Dell 1953: 231) and as a junior synonym of U. menziesii by McMichael & Hiscock (1958: 460), Powell (1979: 384) and Marshall et al. (2014: 10). The last-mentioned species is endemic to New Zealand, and is widely distributed in lakes, rivers and streams in the North and South Islands, and on Great Barrier Island ( Marshall et al. 2014: 12, fig. 6).

Current taxonomy. A junior synonym of Echyridella menziesii (Gray, 1843) — McMichael & Hiscock (1958: 460 —in Hyridella ( Echyridella )), Powell (1979: 384 —in Hyridella), Marshall et al. (2014: 10).