Zonites helmsii 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 : 26-27

Zonites helmsii Hutton, 1882

Pl. 2, fig. H

Hutton, 1882. New Zealand Journal of Science, 1: 281.

Type material. Lectotype (designated here), CMNZ M12783 [ex M254], and paralectotypes, CMNZ M254 (6), CMNZ M1068 [ex ZS 653] (3), NMNZ M.275691 [ex H. Suter colln.] (4) (dry shells). The molluscan collection

at CMNZ has radulae and jaws mounted on glass slides with the label details ‘ Phacussa helmsi, Greymouth, XVI p. 172’, in Hutton’s handwriting (i.e., CMNZ 2017.17.117–119), which are probably primary type material (see descriptions of radula and jaw by Hutton 1883d: 138, 1884b: 172–173).

Label details. CMNZ M254—‘42. Phacussa helmsi Hutton , Greymouth’, pillboxlabel—in Hutton’s handwriting; NMNZ M.275691—’18. Flammulina Phacussa helmsi, Hutt., Hel. , Greymouth’, in H. Suter’s handwriting.

CMNZ molluscan catalogue details. M1068—‘ Phacussa helmsi Hutton, Greymouth (old number ZS 653)’.

Type locality. ‘Greymouth (R. Helms)’ ( Hutton 1882p: 281, 1883d: 138).

Previous illustrations of type material. Jaw and radula teeth illustrated by Hutton (1884b: pl. 10, fig. I, pl. 11, fig. W) probably from type material.

Remarks. Hutton submitted a description of this species to the Transactions and Proceedings of the New Zealand Institute issue for 1882, but publication was delayed until May 1883 ( Hutton 1883d: 137), and was preempted by a brief description in an account of a meeting of the Philosophical Institute of Canterbury ( Hutton 1882p: 281). A shell from the type series ( lectotype) is illustrated here for the first time in pl. 2, fig. H. The species name has been consistently listed as helmsi by New Zealand authors from Hutton (1884b: 172, 1884c: 205) onwards (e.g., Suter 1913: 624, Powell 1979: 315, Spencer et al. 2009: 215), and because this subsequent spelling has been in prevailing use since 1884 it is deemed to be correct under ICZN Articles 33.4 and 33.3.1. Descriptions by Hutton (1884b: 172–173, pl. 10, fig. I, pl. 11, fig. W) of the jaw and radula of helmsi were probably based on the putative type material in CMNZ 2017.17.117–2017.17.119 mentioned above. Zonites helmsi is the type species of Phacussa Hutton, 1883 , by subsequent designation of Pilsbry (1893 [in 1893–1895]: 12). Phelussa Iredale, 1915 is an unnecessary replacement name for Phacussa Hutton, 1883 . Phacussa helmsi has been interpreted as having a wide distribution in the southern South Island (e.g., Suter 1913: 625; Powell 1979: 315), but this refers to a species complex (M. Kennedy unpub. data), and the identity and distribution of Hutton’s species needs to be re-evaluated. At present it is known definitely from the West Coast only (below).

Current taxonomy. Phacussa helmsi (Hutton, 1882) — Hutton (1884b: 172, 1884c: 205), Suter (1913: 624), Powell (1979: 315), Spencer et al. (2009: 215).

Distribution. New Zealand; South Island, West Coast, between Greymouth and Westport (AIM and NMNZ collection records).