Phrixgnathus celia 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 : 40-41

Phrixgnathus celia Hutton, 1883

Pl. 5, fig. B

Hutton, 1883. The New Zealand Journal of Science, 1: 476.

Type material. Lectotype (designated here), CMNZ M1375.1 , and paralectotypes (6), CMNZ M1375.2 – 7 (dry shells).

Label details. ‘Dunedin, F.W. Hutton Coll. pill box no. 112’.

CMNZ molluscan catalogue details. M1375—‘ Phrixgnathus celia Hutton, Dunedin (8 specimens) (old No. 112) ’.

Type locality. ‘Dunedin (F.W.H.)’ ( Hutton 1883g: 476, 1884b: 176).

Previous illustrations of type material. Jaw and radula illustrated by Hutton (1882h: pl. 3, fig. N, pl. 4, fig. N), which was incorrectly identified as Helix fatua Pfeiffer (see Hutton 1884b: 176), possibly from type material of Phrixgnathus celia Hutton, 1883 .

Remarks. Hutton submitted a description of Phrixgnathus celia to the Transactions and Proceedings of the New Zealand Institute issue for 1883, but publication was delayed until May 1884 ( Hutton 1884b: 176), and was preempted by a brief description in an account of a meeting of the Philosophical Institute of Canterbury ( Hutton 1883g: 476). This is a morphologically variable species, with shells differing in spire elevation, spire angle and umbilical width, both within and between local populations. This is evident in the type material, which was collected by Hutton himself. The lectotype, illustrated here for the first time in pl. 5, fig. B, has a relatively high spire compared to some paralectotypes. There has been considerable confusion over the taxonomy and distribution of P. celia . Initially, Hutton (1882h: 153 —see Hutton 1884b: 176) incorrectly identified material of this species as Helix fatua Pfeiffer, 1857 , which is in fact a subjective junior synonym of Therasiella celinde (Gray, 1850) ( Brook & Ablett 2019: 43) . Hutton (1884c: 197) recorded P. celia from the South Island and southern North Island, and Hedley & Suter (1893: 648), Suter (1894b: 279, 1913: 749) and Powell (1979: 326) recorded it from Rakiura/Stewart Island, South Island, and North Island south of Auckland. Examination of museum collections indicates that previous records of P. celia from the North Island were in error, and preliminary genetic analyses indicate that putative South Island records comprise a complex of several species (M. Kennedy unpub. data). On present knowledge celia sensu stricto appears to have a distribution restricted to southern South Island, Whenua Hou/Codfish Island, Rakiura and nearby islands (below). Morphologically similar taxa in northern South Island differ substantially genetically from typical celia , and evidently represent separate species. Examination of type material indicates that Laoma (Phrixgnathus) liratula Suter, 1909 , which was based on material from Stewart Island (i.e., NMNZ M.88227, M.88228), and Thalassohelix pygmaea Suter, 1913 , based on material from Woodhaugh, Otago [= Dunedin] (i.e., NMNZ M.125165), are subjective junior synonyms of Phrixgnathus celia Hutton, 1883 . Laoma (Phrixgnathus) celia alboviridis Suter, 1913 , based on material from ‘Mt Alfred, Otago’ (i.e., NMNZ M.88225, M.88226), is very similar morphologically to typical celia , and may also be a synonym. Laoma (Phrixgnathus) celia levis Suter, 1913 , which is based on material from Pipiriki, Wanganui River (i.e., NMNZ M.88134), was listed as a junior synonym of P. celia Hutton, 1883 by Powell (1979: 326), but appears to us to be a separate species that has a distribution between Whanganui and Port Waikato, western North Island. Powell (1979: 330) suggested that Laoma (Phrixgnathus) trailli Suter, 1909 , which was based on material from an unknown location (NMNZ M.83445), “looks like a large form of liratula ”, but examination of type material indicates that the two are clearly different species. Phrixgnathus celia was incorrectly listed as the type species of Phrixgnathus Hutton by some authors (e.g., Pilsbry, 1893 [in 1893–1895]: 9, Suter 1913: 738, Thiele 1931 [in 1929–1935]: 567, Solem 1959: 81, Zilch 1959 [in 1959–1960]: 205, Powell 1979: 325, Spencer & Willan 1996: 41, Schileyko 2002: 1048).

Current taxonomy. Phrixgnathus celia Hutton, 1883 — Hutton (1884b: 176), Spencer et al. (2009: 217).

Distribution. New Zealand; southern South Island, Fiordland to eastern Otago; Rakiura and nearshore islands;

Whenua Hou (AIM and NMNZ collection records; M. Kennedy unpub. data).