Islandiella helenae Feyling-Hanssen and Buzas, 1976

Setoyama, Eiichi & Kaminski, Michael A., 2015, Neogene benthic foraminifera from the southern Bering Sea (IODP Expedition 323), Palaeontologia Electronica (International ed. in English) 76 (4), pp. 1-30 : 7

Islandiella helenae Feyling-Hanssen and Buzas, 1976

Figures 3.13a–d , 5.2a–c , 8.6

1976 Islandiella helenae Feyling-Hanssen and Buzas : p. 155, figs. 1–4.

1980 Islandiella helenae Feyling-Hanssen and Buzas ; Rodrigues, Hooper, and Jones, p. 49, pl. 1, figs. 1, 3, 5, pl. 4, figs 3, 6, 9, pl. 6, figs. 1, 2.

1983b Islandiella helenae Feyling-Hanssen and Buzas ; Nomura, p. 16, pl. 2, figs. 4a–c, 5a–c, pl. 7, figs. 11, 12, pl. 8, figs 1, 2.

1999 Planocassidulina helenae (Feyling-Hanssen and Buzas) ; Nomura, p. 51, figs. 33- 1a-c, -2a-c, 36-1, -2.

Remarks. The size and the convexity of test vary greatly among specimens. The identification criteria of the species in this study follow Nomura (1983b), and it is distinguished from Islandiella norcrossi ( Cushman, 1933) by possessing roundedrhomboid to oval chambers, but not triangular chambers in mature specimens, and the different position of the aperture. Although the species was transferred to the genus Planocassidulina Gudina (1966) emended by Nomura (1999) from Islandiella by Nomura (1999) based on the acute and sometimes almost keeled periphery of I. helenae and I. norcrossi , the angle of periphery often varies among specimens, and they do not possess a proper keel. We therefore retain the species in the genus Islandiella .

Figures

FIGURE 3. All scale bars are 100 µm. 1. Pyrgo murrhina, 13H-3, 146–148 cm; a. lateral view; b. apertural view. 2. Pyrgo sp. A, 13H-3, 146–148 cm; a. lateral view; b. apertural view. 3. Triloculina cf. Triloculina trihedra, 9H-5, 146– 148 cm; a. lateral view; b. apertural view. 4. Bolivina seminuda, 3H-CC, lateral view. 5. Bolivina sp. A, 36H-CC; a. lateral view; b. edge view showing the asymmetrically positioned aperture. 6. Brizalina pacifica, 11H-5, 146–148 cm; a. lateral view; b. edge view. 7. Brizalina panayensis, 1H-CC; a. lateral view; b. edge view. 8. Bolivinita quadrilatera, 61X-5, 115–117 cm; a. lateral view; b. edge view showing the asymmetrically positioned aperture. 9. Takayanagia cf. Takayanagia cushmani, 1H-CC; a. ventral view showing the tooth plate; b. dorsal view; c. edge view. 10. Rutherfordoides tenuis, 10H-3, 146–148 cm; a. ventral view; b. dorsal view. 11. Globocassidulina neomargareta, 9H-5, 146– 148 cm; a. ventral view; b. apertural view showing the tooth plate; c. dorsal view; d. edge view. 12. Globocassidulina subglobosa, 13H-3, 146–148 cm; a. ventral view; b. dorsal view; c. edge view. 13. Islandiella helenae, 12H-3, 146– 148 cm; a. ventral view; b. ventral view in immersion; c. dorsal view; d. edge view. 14. Globocassidulina sp. A, 3H- CC; a. ventral side, b. dorsal side, c. edge view.

FIGURE 5. All scale bars are 100 µm. 1. Valvulineria cf. Valvulineria sadonica, 4H-CC; a. dorsal view; b. ventral view; c. edge view. 2. juvenile form of Islandiella helenae?, 1H-CC; a. ventral view; b. dorsal view; c. edge view. 3. Alabaminella weddellensis, 13H-3, 146–148 cm; a. dorsal view; b. ventral view; c. edge view. 4. Cibicidoides mundulus, 18H- 3, 146–148 cm; a. ventral view; b. dorsal view; c. edge view. 5. Cibicidoides simplex, 1H-CC; a. ventral view; b. dorsal view; c. edge view. 6. Parrelloides healdi, 1H-CC; a. dorsal view; b. ventral side view; c. edge view showing the porelike aperture. 7. Parrelloides healdi, 25H-5, 146–148 cm; a. spiral view; b. umbilical view; c. edge view showing the pore-like aperture. 8. Epistominella pulchella, 4H-CC; a. spiral view; b. umbilical view; c. edge view showing the elongate arch aperture. 9. Laticarinina pauperata, 52H-CC. 10. Cibicidoides wuellerstorfi, 10H-3, 146–148 cm; a. ventral view; b. dorsal view; c. edge view. 11. Nonionella digitata, 9H-5, 146–148 cm; a. dorsal view; b. edge view; c. ventral side.

FIGURE 8. All scale bars are 100 µm. 1. Bolivina sp. A, 1H-CC, lateral view. 2. Brizalina pacifica, 3H-CC, lateral view. 3. Brizalina panayensis, 3H-CC, lateral view. 4. Takatanagia cf. Takayanagia cushmani, 1H-CC, lateral view showing the apertural plate. 5. Rutherfordoides tenuis, 16H-5, 146–148 cm, lateral view. 6. Islandiella helenae, 13H-3, 146– 148 cm, lateral view. 7. Eubuliminella exilis, 1H-CC, lateral view. 8. Eubuliminella cf. Eubuliminella exilis, 3H-CC, lateral view. 9. Fursenkoina complanata, 3H-CC, lateral view. 10. Globobulimina cf. Globobulimina spinescens, 61X-5, 115–117 cm, lateral view. 11. Uvigerina proboscidea, 59X-3, 145–147 cm, lateral view. 12. Uvigerina senticosa, 8H-5, 146–148 cm, lateral view. 13. Rutherfordoides erectus, 1H-CC, lateral view. 14. Siphonodosaria? sp. A, 36H-5, 148– 150 cm, lateral view. 15. Siphonodosaria? sp. B, 13H-5, 146–148 cm, lateral view. 16. Stilostomella fistuca, 36H-CC, lateral view. 17. Laticarinina pauperata, 61X-CC, lateral view. 18. Nonionella digitata, 3H-CC, lateral view. 19. Nonionellina labradorica, 3H-CC, lateral view. 20. Nonionellina cf. Nonionellina labradorica, 3H-CC, lateral view. 21. Elphidium batialis, 3H-CC, lateral view. 22. Lotostomoides calomorphum, lateral view. 23. Neugeborina longiscata, 16H-5, 146–148 cm, lateral view. 24. Laevidentalina californica, 26H-CC, lateral view. 25. Laevidentalina sp. A, 36H-5, 148– 150 cm, lateral view. 26. Mucronina sp. A, 61X-CC, lateral view. 27. Astacolus sp., 22H-CC, lateral view. 28. Procerolagena gracillima, 16H-5, 146–148 cm, lateral view. 29. Lagena hispidula, 13H-5, 146–148 cm, lateral view. 30. Lagena striata, 8H-3, 146–148 cm, lateral view. 31. Oolina squamosa, 9H-5, 146–148 cm, lateral view. 32. Parafissurina caledoniana, 8H-CC, lateral view.