Cribroelphidium sp. A

Hanagata, S & Nobuhara, T, 2015, Illustrated guide to Pliocene foraminifera from Miyakojima, Ryukyu Island Arc, with comments on biostratigraph, Palaeontologia Electronica (Cambridge, England) 33 (8), pp. 1-142 : 121

Cribroelphidium sp. A

Figures 36.7, 36.8

Description. Test small for the genus, planispiral and involute, both sides almost parallel, five chambers in final whorl; chambers inflated; sutures depressed and retral process appearing as small pores; umbilical area filled by shell material; periphery broadly rounded; aperture interiomarginal slit; surface smooth and moderately perforated.

Remarks. We could not find a named species to refer this to. It is characterized mainly by the small number of chambers in a whorl and the inflated, thick test.

Occurrence. Rare in the Yonahama and Minebari formations.

Figures

FIGURE 36. Family Rotaliidae and Elphidiidae. All scale bars = 0.1mm, unless otherwise indicated. 1, 2. Rotalinoides gaimardii (Fornasini), 1: MPC-26468 from sample 3-2-up-sand (Onogoshi Formation, PL1); 2: MPC-26469 from sample 18 (Oura F.,?PL1). 3, 4. Cribroelphidium clavatum (Cushman), 3: MPC-26210 from sample 2 (Minebari F., PL5); 4: MPC-26211 from sample MK02B (Minebari F., PL5). 5, 6. Cribroelphidium subincertum (Asano), 5: MPC-26212 from sample 1 (Minebari F., PL5); 6: MPC-26213 from sample 1-2 (Minebari F., PL5). 7, 8. Cribroelphidium sp.A, 7: MPC-26214 from sample 14 (Yonahama F., PL4); 8: MPC-26215 from sample 14-2 (Yonahama F., PL4). 9, 10. Elphidium advenum (Cushman), 9: MPC-26232 from sample 5 (Minebari F., PL5); 10: MPC-26233 from sample MK02A (Minebari F., PL5). 11, 12. Elphidium crispum (Linnaeus), 11: MPC-26234 from sample 2 (Minebari F., PL5); 12: MPC- 26235 from sample 16 (Yonahama F., PL3). 13, 14. Elphidium aff. neosimplex (McCulloch), 13: MPC-26236 from sample 11 (Onogoshi F.,?PL1); 14: MPC-26237 from sample 18 (Oura F.,?PL1). 15. Elphidium planulatum (Lamarck), MPC-26238 from sample 5-2 (Minebari F., PL5); broken specimen.