Phrixgnathus titania 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 : 46-47

Phrixgnathus titania Hutton, 1883

Pl. 6, fig. A

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

Type material. Lectotype, CMNZ M1388 (dry shell) . Lectotype fixed by inference of holotype ( ICZN Art. 74.6) by Powell (1979: 330) .

Label details. ‘115. Phrixgnathus titania Hutton , Dunedin’, pillbox label in Hutton’s handwriting.

Type locality. ‘Dunedin (Hutton)’ ( Hutton 1883g: 476, 1884b: 177).

Previous illustrations of type material. Pilsbry (1892 [in 1892–1893]: 62, pl. 23, figs. 82–84—‘the type specimen is figured’); Suter (1915: pl. 30, fig. 10).

Remarks. The original description of this species was based on one or more specimens collected by Hutton himself. He submitted a description of this species to the Transactions and Proceedings of the New Zealand Institute issue for 1883, but publication was delayed until May 1884 ( Hutton 1884b: 177), and was pre-empted by a brief description in an account of a meeting of the Philosophical Institute of Canterbury ( Hutton 1883g: 476). Suter (1913: 762) noted “the only specimen I have seen is the type”. Powell (1979: 330) listed titania as a species of uncertain status, noting “the writer has not seen the holotype, the only known specimen. From Suter’s (1913, p. 762) description and figure (1915, pl. 30, fig. 10) the specimen is obviously abnormal in its coiling, and may prove to be [ Phrixgnathus ] celia ”. However, examination of type material indicates that titania and celia are separate species, differing in umbilical width, spire profile, teleoconch microsculpture and colour pattern. Phrixgnathus titania was recorded from Dunedin only by Suter (1913: 762) and Powell (1979: 330), but museum collection records indicate that it has a wider distribution in southeastern South Island, which in part overlaps that of celia (see above).

Current taxonomy. Phrixgnathus titania Hutton, 1883 — Hutton (1884c: 198), Spencer et al. (2009: 217).

Distribution. New Zealand; southeastern South Island, East Otago and South Canterbury ( Goulstone 1991: 15; AIM and NMNZ collection records).

Family RHYTIDIDAE Pilsbry, 1893