Epistominella pulchella Husezima and Maruhasi

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 : 12-14

Epistominella pulchella Husezima and Maruhasi ,

1944

Figure 5.8a–c

1944 Epistominella pulchella Husezima and Maruhashi : p. 398, pl. 34, fig. 10.

1992 Epistominella pulchella Husezima and Maruhashi ; Kato, p. 386, pl. 3, figs. 2–4.

Description. Test small to medium, low trochospiral with seven chambers in the final whorl. The umbilical side is more inflated than the spiral side, which is only slightly convex. Periphery acute. Umbilicus closed. Chambers increasing in size gradually. Sutures clear, depressed, curved backwards on the spiral side, less so on the umbilical side. Wall smooth, finely perforated. Aperture an elongate arch at the base of the last chamber. Apertural face somewhat dented.

Remarks. This species is very similar to Epistominella smithi ( Stewart and Stewart, 1930) described from the lower Pliocene of California, but based on the definition the former differs from the latter by possessing more chambers in the final whorl (seven instead of five to six) and E. smithi seems to have a more prominent keel. It differs from Epistominella exigua ( Brady, 1884) by its planoconvex test and less lobulated periphery.

Figures

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.