Hydrocena purchasi Pfeiffer, 1861

Brook, Fred J. & Ablett, Jonathan D., 2019, Type material of land snails (Mollusca: Gastropoda) described from New Zealand by taxonomists in Europe and North America between 1830 and 1934, and the history of research on the New Zealand land snail fauna from 1824 to 1917, Zootaxa 4697 (1), pp. 1-117 : 16

Hydrocena purchasi Pfeiffer, 1861

Pfeiffer, 1861. Malakozoologische Blätter, 8: 150.

Type material: Listed by Suter (1913b: 176) as being in the ‘ K.K. Hofmuseum, Vienna’, but not found during a search of the collections in the Naturhistorisches Museum Wien in 2014 (Anita Eschner pers. comm.). As noted in the Introduction (above), the type material may have gone to the Pommersches Museum, Stettin [= Szczecin], after Pfeiffer’s death in 1877, in which case it has probably been lost or destroyed .

Type locality: ‘ Bay of Islands’ ( Pfeiffer 1861: 150) .

Remarks: The original description was based on one or more specimens obtained by Ferdinand von Hochstetter during his visit to New Zealand in 1858–1859. The shell dimensions were given as “Long. 2, diam. 1 mill” ( Pfeiffer 1861: 150). There are no published illustrations of the type material, but Pfeiffer’s description is sufficient to determine the identity of this taxon, the only known representative of family Hydrocenidae in New Zealand, without ambiguity.

Current Taxonomy: Listed as Georissa purchasi ( Pfeiffer, 1861) by Spencer & Willan (1995: 17) and Spencer et al. (2009: 203).

Distribution: New Zealand; North, South, and Three Kings islands (Suter 1913b—in Hydrocena ; Climo 1973 —in Omphalorissa Iredale, 1933 ; Powell 1979 —in Omphalorissa ).