Nonionellina labradorica (Dawson)

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 : 107-108

Nonionellina labradorica (Dawson)

Figures 31.19, 31.20

1860 Nonionina labradorica Dawson , pp. 191, 192, text-fig. 4.

1938 Nonion scaphum Fichtel and Moll — Asano (b), pp. 593, 594, pl. 15, fig. 4 (non Nautilus scapha Fichtel and Moll, 1798 ).

1982 Nonionellina labradorica (Dawson) — Saunders and Müller-Merz, pp. 272, 273, pl. 2, figs. 14—18.

1987 Nonionellina labradorica (Dawson) — Loeblich and Tappan, pl. 689, figs. 8—17.

1988 Nonion scaphum (Fichtel and Moll) — Marle, p. 147, pl. 4, fig. 8.

1989 Nonionellina labradorica (Dawson) — Inoue, pp. 157, 158, pl. 24, fig. 3, pl. 32, fig. 13, pl. 33, fig. 3.

Remarks. Asano (1938b) assigned this species to Nautilus scapha Fichtel and Moll , and his identification was followed in subsequent Japanese works. Nonion scaphum is a senior synonym of Nonionina communis d’Orbigny (1846) as demonstrated by Rögl and Hansen (1984). It is distinguished from N. labradorica in a lesser growth rate and more compressed test.

Occurrence. Sporadic in the Minebari Formation.

Figures

FIGURE 31. Family Planulinidae, Cibicididae, Epistomariidae, Amphisteginidae, and Nonionidae. All scale bars = 0.1mm. 1, 2. Planulina retia Belford, 1: MPC-26416 from sample 2 (Minebari Formation, PL5); 2: MPC-26417 from sample 5-2 (Minebari F., PL5). 3, 4. Cibicides refulgens de Montfort, 3: MPC-26197 from sample 2-2 (Minebari F., PL5); 4: MPC-26198 from sample 14-2 (Yonahama F., PL4). 5. Cibicides tenuimargo (Brady), MPC-26199 from sample 4-2 (Minebari F., PL5); stripe pattern on the dorsal side implies attached material. 6, 7. Fontbotia wuellerstorfi (Schwager), 6: MPC-26272 from sample MK01 (Yonahama F., PL2); 7: MPC-26273 from sample MK02A (Minebari F.,PL5).8, 9. Lobatula lobatula (Walker and Jacob), 8: MPC-26367 from sample 5 (Minebari F., PL5); 9: MPC-26368 from sample 5-2 (Minebari F., PL5). 10, 11. Dyocibicides biserialis Cushman and Valentine, 10: MPC-26224 from sample 2-2 (Minebari F., PL5); 11: MPC-26225 from sample 3-2-up-sand (Onogoshi F., PL1). 12—14. Pseudoeponides japonicus Uchio, 12: MPC-26430 from sample 14 (Yonahama F., PL4); 13: MPC-26431 and 14: MPC-26548 from sample MK02B (Minebari F., PL5); arrows in 14 shows slit opening along dorsal sutures. 15, 16. Amphistegina lessonii d'Orbigny, 15: MPC-26123 from sample 2 (Minebari F., PL5); 16: MPC-26124 from sample 2-2 (Minebari F., PL5); all specimens of this study are juveniles. 17, 18. Nonion japonicum Asano, 17: MPC-26392 from sample 5-2 (Minebari F., PL5); 18: MPC-26393 from sample 11 (Onogoshi F.,?PL1). 19, 20. Nonionellina labradorica (Dawson), 19: MPC-26394 from sample 1-2 (Minebari F., PL5); 20: MPC-26395 from sample MK02B (Minebari F., PL5). 21, 22. Pseudononion cuevasensis Saunder and Müller-Merz, 21: MPC-26438 from sample 10 (Onogoshi F., PL2); 22: MPC-26439 from sample MK02B (Minebari F., PL5). 23, 24. Pseudononion subcostatum Fujita and Ito, 23: MPC- 26440 from sample 14-2 (Yonahama F., PL4); 24: MPC-26441 from sample MK02B (Minebari F., PL5).