Rhytida australis Hutton, 1882

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 : 47

Rhytida australis Hutton, 1882

Pl. 6, fig. C

Hutton, 1882. The New Zealand Journal of Science, 1: 282.

Type material. Lectotype (designated here), CMNZ M1406 (dry shell). The molluscan collection at CMNZ has a radula mounted on a glass slide with the label details ‘ Rhytida australis, Stewart Island, XVI p. 167’, in Hutton’s handwriting (i.e., CMNZ 2017.17.61), which is probably primary type material (see radula descriptions by Hutton 1883d: 139; 1884b: 167).

Label details. CMNZ M1406—‘Stewart Is., Hutton coll. (123)’.

CMNZ molluscan catalogue details. M1406—‘ Rhytida australis Hutton, Stewart Island (1 specimen) (old No. 123) ’.

Type locality. ‘Stewart Island (T. Kirk)’ ( Hutton 1882p: 282, 1883d: 139).

Previous illustrations of type material. Radula teeth illustrated by Hutton (1884b: pl. 10, fig. S) probably from type material.

Remarks. Original description based on one or more specimens from Rakiura/Stewart Island. Hutton submitted a description of Rhytida australis to the Transactions and Proceedings of the New Zealand Institute issue for 1882, but publication was delayed until May 1883 ( Hutton 1883d: 139), and was pre-empted by a brief description in an account of a meeting of the Philosophical Institute of Canterbury ( Hutton 1882p: 282). A description by Hutton (1884b: 167, pl. 10, fig. S) of a radula of australis was probably based on the putative type material in CMNZ 2017.17.61 mentioned above. A shell from the type material (lectotype) is illustrated here for the first time in pl. 6 fig. C. Assigned to genus Rhytida Albers, 1860 [in Albers & Martens, 1860] by Hutton (1882) and subsequent authors, but preliminary results of a phylogenetic study (M. Kennedy & T. King unpub. data) indicate that this placement requires re-evaluation.

Current taxonomy. Rhytida australis Hutton, 1882 — Hutton (1884c: 208), Suter (1913: 771), Dell (1954b: 150), Parkinson (1979: 11), Powell (1979: 344), Efford (1998:33), Spencer et al. (2009: 218).

Distribution. New Zealand, Whenua Hou/Codfish Island, Rakiura and nearshore islands ( Dell 1954b: 150; Powell 1979: 344; Efford 1998: 33, fig. 4f; AIM and NMNZ collection records).