Pachylabra turbinis var. lacustris Annandale, 1920

Tripathy, Basudev, Sajan, Sheikh & Cowie, Robert H., 2019, Illustrated catalogue of types of Ampullariidae Gray, 1824 (Mollusca, Gastropoda) in the National Zoological Collection of the Zoological Survey of India, with lectotype designations, Zoosystematics and Evolution 96 (1), pp. 1-23 : 1

Pachylabra turbinis var. lacustris Annandale, 1920 Figs 7 , 13C

Pachylabra turbinis Race lacustris Annandale, 1920. J. Nat. Hist. Soc. Siam 4: 20, pl. 1, fig. 8 [as “var.”].

Current taxonomic status.

Pila ampullacea (Linnaeus, 1758), junior synonym ( Brandt 1974; Ng et al. 2014).

Type locality.

"edge of the inner or freshwater region of the Tale Sap or Inland Sea of Singgora" ( Annandale 1920: 20), "Tale Sap, near Lampam, Siam" ( Annandale 1920: description of pl. 1, fig. 8) [= Muang Phatthalung District, Phatthalung, Thailand]; Annandale, leg.

Type material.

Lectotype (here designated): NZSI M.10511/2 (registered 10 June 1916). Paralectotypes: NZSI M.33448/9 (ex. NZSI M.10511/2, originally registered 10 June 1916, newly registered as NZSI M.33448/9 9 October 2019, 2 spms).

Shell dimensions.

Lectotype: SH 74.0 mm, SW 73.8 mm, AH 63.2 mm, AW 34.8 mm, OH, OW (operculum not found). Paralectotypes (2 spms): SH 67.2, 75.6 mm, SW 64.0, 72.5 mm, AH 56.7, 63.8 mm, AW 31.2, 33.6 mm, OH 54.2 mm, OW 30.0 mm (1 spm., operculum damaged).

Remarks.

In the heading of the description, Annandale (1920: 20) treated Ampullaria lacustris as a “Race” of Pachylabra turbinis Lea, in his text as a “form” ( Annandale 1920: 20) and in the description of pl. 1, fig. 8 and on the label (Fig. 13C ) as a “var.”. Following the Code (Art. 45.6.4), it is therefore considered to have been described as a subspecies and thus Ampullaria lacustris is an available name. Annandale (1920: 21) designated the “Type-specimen” (= holotype) as NZSI M.11571/2. However, the shell illustrated in Fig. 7 is unquestionably the shell illustrated in Annandale’s (1920: pl. 1, fig. 8) plate, the legend of which says “Type-specimen” (specifically, the wear of the periostracum matches Annandale’s illustration exactly). This specimen has the number “10511” written inside the aperture and is in a box with two very similar shells with labels that also have this number. This is not the shell in NZSI M.11571/2, which is more conical-shaped with a more protruding spire and a more crescent-shaped aperture, much smoother and less rugose, and much thinner and less robust, and which appears to be a different species. In these regards, it does not match Annandale’s description, whereas the shells in NZSI M.10511/2 do. Thus, two specimens could be considered to have been designated as the holotype by Annandale, the one in NZSI M.11571/2 and the one illustrated in his fig. 8, which is one of the three in NZSI M.10511/2. However, saying “Type-specimen” in the legend of fig. 8 does not designate this specimen as the holotype because it could be construed as simply referring to a type specimen not the type specimen. The description was based on only three specimens, i.e. because there is a table of dimensions of three specimens and no others were mentioned. The measurements of the three shells in the original NZSI M.10511/2 lot match those given in the table within a reasonable margin of error. The shell in NZSI M.11571/2 is smaller and its body whorl is badly broken. The original Indian Museum register gives the locality of NZSI M.10511/2 as "Mouth of the Patalung River at Lampam", which matches the location given by Annandale in the legend of his fig. 8, whereas the register entry for NZSI M.11571/2 gives a different locality, “Koh-Si-Hah”, which refers to islands a little further south in the Tale Sap. Although the Indian Museum register indicates two specimens in NZSI M.10511/2, this is corrected to three specimens in the later type register of the ZSI, which does not list NZSI M.11571/2. Cowie (2015: 39) noted the “holotype” [by original designation] as NZSI M.11571/2 and four possible paratypes as NZSI M.10511/2, for a total of five specimens, including the holotype. Detailed study now indicates that only the three (not four) specimens in NZSI M.10511/2 constitute the type series. The only explanation we can think of for Annandale having designated NZSI M.11571/2 as the holotype was that he did this mistakenly, as it is very likely that he would have illustrated the specimen he considered the holotype and it is unlikely that he would have designated a badly damaged specimen (if indeed it were damaged at the time) as the holotype; and in any case, as noted above, this latter specimen does not match the description or measurements given by Annandale. On this basis, we here designate the specimen illustrated by Annandale (1920: pl. 1, fig. 8) as the lectotype in order to fix the concept of Ampullaria lacustris Annandale and to preclude further confusion. It retains the catalogue number NZSI M.10511/2. The other two specimens in the original NZSI M.10511/2 lot are re-registered as NZSI M.33448/9 and are paralectotypes. The single specimen in NZSI M.11571/2 is considered to have no type status.

Figures

Figure 7. Lectotype of Pachylabra turbinis var. lacustris Annandale, 1920; NZSI M. 10511 / 2.

Figure 13. Collection labels. A. Ampullaria globosa var. incrassatula Nevill, 1877; NZSI M. 25083 / 5. B. Ampullaria ampullacea var. javensis Nevill, 1885 (referred to as the unpublished name " subcelebensis "; see text for explanation); NZSI M. 27736 / 6. C. Pachylabra turbinis Race lacustris Annandale, 1920; NZSI M. 10511 / 2 (lectotype).