Fluxinella membranacea, Helwerda, Renate Ariane, Wesselingh, Frank Pieter & Williams, Suzanne T., 2014

Helwerda, Renate Ariane, Wesselingh, Frank Pieter & Williams, Suzanne T., 2014, On some Vetigastropoda (Mollusca, Gastropoda) from the Plio-Pleistocene of the Philippines with descriptions of three new species, Zootaxa 3755 (2), pp. 101-135 : 111

Fluxinella membranacea Marshall, 1991

( Figures 16–17 )

1991 Fluxinella membranacea sp. nov. — Marshall, 1991: p. 68, figs 91, 93, 94. 2006 Fluxinella membranacea —Poppe et al.: p. 23, pl. 2, fig. 4.

2008a Fluxinella membranacea —Poppe & Tagaro: p. 160, pl. 25, fig. 4.

Material. Anda 1 (28); Anda 2 (41); Anda 3 (26); Anda 4 (37); Anda 5 (2); Anda 6 (5); AndaDeVos (15); AndaClif1 (1); AndaClif3 (2); Roxas (3).

Characterization. Shell very low domed, H 0.9 mm, W 2.1 mm, disk-shaped, smooth and shiny; P small, smooth, 1.1 whorls, DN 0.10 mm; T growth lines very fine, sigmoid; prominent keel on periphery; umbilicus wide.

Distribution. Shells of Fluxinella membranacea have been reported from off southern New Caledonia, 250– 440 m depth ( Marshall 1991) and from Balicasag Island, Philippines, from 242–400 m depth ( Poppe et al. 2006).

Remarks. The specimen shown by Marshall (1991) is similar to the shells in the studied material. The specimen shown by Poppe et al. (2006, pl. 2, fig. 4) has a more pronounced folded columellar lip, a more pronounced shoulder and median keel than the fossil material as well as the material shown by Marshall (1991). More material is required to investigate whether these differences represent intraspecific variation.

Figures

FIGURES 13 – 17. Seguenziidae. 13. Halystina conoidea nov. spec. RGM 608.229 (holotype). Locality AndaDeVos. (a) rear view, (b) apertural view, (c) side view, (d) basal view, (e) apical view. 14. Halystina conoidea nov. spec. RGM 608.230 (paratype). Locality Anda 6. (a) rear view, (b) apertural view, (c) side view, (d) basal view, (e) apical view. 15. Halystina conoidea nov. spec. RGM 608.231 (paratype). Locality AndaDeVos. SEM detail of protoconch. 16. Fluxinella membranacea Marshall, 1991. RGM 608.239. Locality Anda 1. (a) rear view, (b) apertural view, (c) basal view, (d) apical view. 17. Fluxinella membranacea Marshall, 1991. RGM 608.240. Locality Anda 1. (a) apical view, (b) SEM detail of surface sculpture.