Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines

Helwerda, Renate A. (2015): Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines. Zootaxa 3990 (2): 197-220, DOI: http://dx.doi.org/10.11646/zootaxa.3990.2.

Anatoma porcellana Geiger 2012

Anatoma porcellana Geiger, 2012 (Figures 8–9) 2012 Anatoma porcellana nov. spec.—Geiger: p. 1020–1026, figs 830–833. Material. Anda 5 (1) RGM 961.716, Anda 6 (9) RGM 961.718, AndaCliff 3 (5) RGM 961.720, Tiep 1 (1) RGM 961.721. Characterization. Shell large, biconical; H 3.95 mm, W 3.97 mm; P eroded, DN 0.13–0.16 mm; shoulder with curved axial cords and 1–3 fine spiral lines; base with spiral and axial cords forming reticulate sculpture; sculpture weakens on lower third of base; aperture rounded; umbilicus closed. Distribution. Possibly tropical Indian Ocean; southern Japan, Indo-Malayan Archipelago to the Western Pacific, 49–2570 m (Geiger 2012). Remarks. The studied material mostly conforms to the description by Geiger (2012), although some specimens are larger than 3.2 mm (largest is 3.95 mm). The shoulder occasionally has three fine spiral lines instead of one to two. The density of axial cords on shoulder and base strongly increases on the last whorl of large specimens. P and T 1 are eroded in the studied material, yet T 1 appears to have only about 11 axial ribs instead of 17–20. The studied material is quite similar in its shape, sculpture and closed umbilicus to Anatoma gephyra Maxwell, 1992 from the late Eocene of New Zealand as well, but the latter has a shorter T 1 of only 0.33 whorls.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on pages 187-189, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Zeidora geigeri

Zeidora geigeri nov. spec. (Figure 12) Type material. Holotype RGM 961.724. Type locality. Anda 2, Pangasinan, Philippines, Santa Cruz Formation, Pliocene or Early Pleistocene, 16 º 17 ′ 24.8 ′′ N 119 º 56 ′ 11.8 ′′ E. Derivatio nominis. Named after Daniel L. Geiger (Santa Barbara Museum of Natural History), authority on Vetigastropoda. Diagnosis. Shell patelliform, elongated; L> 4.54 mm; H 2.25 mm; W> 3.50 mm; apex posterior, low, not extending beyond shell outline; protoconch nucleus with anastomosing ridges; teleoconch sculpture of about 80 primary radial ribs, commarginal ribs forming small nodules on radial ribs; selenizone distinct; posterior septum narrow. Description. Shell small, ovate, whitish, fragile. Spire low, located posteriorly, slightly twisted to right side, nearly reaching but not extending beyond shell outline. Protoconch of 1.1 whorls, located on right side of spire, terminated by a distinct varix. Nucleus sculptured with anastomosing ridges. Teleoconch of 0.9 whorl, elongated, anterior and right side broken. Teleoconch surface sculptured with about 80 fine radial ribs, many commarginal ribs, forming reticulate network with small nodules at intersections. Margins crenulated by radial ribs, crenulations strongest at posteroventral margin. Selenizone moderately narrow, sculptured with curved commarginal ribs, distinct keels on each side. Inner shell surface smooth, shiny. Internal septum located posteriorly, narrow, with slightly thickened rim. Differentiation. There are fourteen Recent species and two fossil species of Zeidora. All of these species differ from Zeidora geigeri nov. spec. because they have a much wider septum and/or a spire that extends beyond the posteroventral margin. Z. tasmanica (Beddome, 1883) from Tasmania, Recent, is most similar in sculpture and shape of the spire, but it has a wider septum. Remarks. The combination of a narrow septum and a spire that does not extend beyond the posteroventral margin in Z. geigeri nov. spec. makes this species unique among the Zeidora species and therefore the description of a new species is justified although it is based on a single, incomplete specimen. The specimen shows enough features for re-identification of additional material found in the future.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on pages 191-192, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Scissurella d'Orbigny 1824

Genus Scissurella d’Orbigny, 1824 Type species. Scissurella laevigata d’Orbigny, 1824 (by subsequent designation Gray 1847: 146); Pliocene–Recent, Mediterranean; Portugal to Angola.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on page 184, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Anatoma equatoria Hedley 1899

Anatoma equatoria (Hedley, 1899) (Figures 6–7) 1899 Scissurella equatoria nov. spec.—Hedley: p. 551–552, fig. 61. 2012 Anatoma equatoria (Hedley, 1899) —Geiger: p. 854–862, figs 686–693. Material. Anda 1 (38) RGM 961710, Anda 2 (32) RGM 961712, Anda 3 (19) RGM 961714, Anda 4 (26) RGM 961715. Characterization. Shell turbiniform; H 1.99 mm, W 2.00 mm; P with flocculent sculpture, DN 0.08–0.10 mm; shoulder with curved axial cords and fine spiral lines; base with spiral and axial lines forming reticulate sculpture; aperture rounded; umbilicus prominent. Distribution. Indo-Mayalan Archipelago to mid-western Pacific, 46–700 m (Geiger 2012).Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on page 187, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines

Helwerda, Renate A., Wesselingh, Frank P. (2014): Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines. Zootaxa 3838 (2): 183-194, DOI: 10.11646/zootaxa.3838.2.

Zeidora A. Adams 1860

Genus Zeidora A. Adams, 1860 Type species. Zeidora calceolina A. Adams, 1860 (by monotypy); Recent, Japan.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on page 191, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Fissurellidae

Fissurellidae indet. Material. Anda 2 (1) RGM 961.725, AndaDeVos (1) RGM 961.726. Description. Only shell fragments available. Commarginal ribs forming knobs on radial ribs. Remarks. Knobs in this material are more dense than in the Emarginula material.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on page 192, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Sukashitrochus morleti Crosse 1880

Sukashitrochus morleti (Crosse, 1880) (Figures 4–5) 1880 Schismope morleti nov. spec.—Crosse: p. 144–146, pl. 4, fig. 3. 1982 Sinezona carinata (A. Adams, 1862) —Ladd: p. 20, pl. 1, figs 3–4. 2012 Sukashitrochus morleti (Crosse, 1880) —Geiger: p. 632–645, figs 496–503, color plate 4 D–E. Material. Anda 2 (1) RGM 961.708, Anda 4 (1) RGM 961.709. Characterization. Shell broad with flattened apex; H 1.03 mm, W 1.29 mm; P with axial sculpture, DN 0.06–0.07 mm; T 1 with distinct axial cords; T 2 with weaker axial cords, prominent spiral keels and weak spiral cords. Distribution. Indo-Malayan Archipelago to Central Pacific, 0–60 m depth, live, in muddy sand (Geiger 2012). Also from the Pleistocene of Vanuatu (Ladd 1982). Remarks. The studied material conforms to the description by Geiger (2012), although specimen RGM 961.709 only has 14 axial cords on T 1 instead of approximately 18.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on page 187, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906

Sinezona marrowi Geiger 2012

Sinezona marrowi Geiger 2012 (Figures 2–3) 2012 Sinezona marrowi nov. spec.—Geiger: p. 500–503, figs 379–381. Material. Anda 1 (1) RGM 961.706, Tiep 2 (1) RGM 961.707. Characterization. Shell with flattened apex and inflated base; H 0.80 mm, W 1.04 mm; P with axial sculpture, DN 0.06–0.09 mm; T 1 with strong prosocline axial lamellae and fine spiral cords; axial lamellae weaker on T 2; aperture large, inclined; umbilical wall straight; umbilical ridge thin but prominent. Distribution. Indian Ocean and Indo-Malayan Archipelago, 0–434 m depth (Geiger 2012). Remarks. The studied material conforms to the description by Geiger (2012), except for the umbilical ridge, which appears to be more prominent in the studied material. The development of the slit cannot be observed in this juvenile material.Published as part of Helwerda, Renate A. & Wesselingh, Frank P., 2014, Revision of Scissurellidae, Anatomidae and Fissurellidae (Gastropoda: Vetigastropoda) from the Plio-Pleistocene of the Philippines, pp. 183-194 in Zootaxa 3838 (2) on page 186, DOI: 10.11646/zootaxa.3838.2.3, http://zenodo.org/record/22906