Eucytherura pacifica, Michael, 1995

Ayress, M. A., Whatley, R., Downing, S. E. & Millson, K. J., 1995, Cainozoic and from Recent Deep Sea Cytherurid Ostracoda the South Western Pacific and Eastern Indian Oceans, Part Cytherurinae, Records of the Australian Museum 47 (2), pp. 203-223 : 215

Eucytherura pacifica n.sp.

Fig. 6 F-I

" Typhlocythere pacifica" Smith, 1983 *: 92, pI. 8 fig. 11.­ Dainty, 1984 *: 219.- Downing, 1985 *: 454; pI. 29, figs 17,18.- Ayress, 1988 *: 634; pI. 22, figs 16 -18.

Etymology. From its occurrence in the south-west Pacific.

Type material and dimensions. Holotype, OS 14086, adult left valve, length 0.34 mm, height 0.22 mm. Paratypes: OS 14087, adult right valve, length 0.31 mm, height 0.19 mm, Site 209, core 2, section 6, interval 75-80 cm, Early Pleistocene, Zone NN 19; OS 14088, adult right valve, length 0.28 mm, height 0.20 mm, Site 208, core 5, section 6, interval 7- 18 cm, Late Pleistocene, Zone NN 21.

Type locality and level. Lord Howe Rise, present day water depth 1428 m, DSDP Site 209, core 2, section 6, interval 75- 80 cm, Early Pleistocene, Zone NN 19 .

Diagnosis. Eucytherura rounded, subrhomboidal lateral outline, tumid posteroventrally. Coarsely reticulate, fossae partially celate. Anterior and posterior marginal and ventral surface microreticulate.

Description. Small, sub-rhomboidal in lateral view. Anterior margin broadly rounded; asymmetrical, extremity below mid-height. Posterior margin convex with very short caudal process sub-dorsally. Dorsal margin slightly sinuous. Ventral margin slightly convex interrupted by posteroventral tumidity. Moderately thick-shelled and tumid posteroventrally, compressed only posteromarginally. Lateral surface coarsely reticulate, fossae mostly polygonal except anteriorly and over posteroventral swelling where fossae are partially celated and well rounded. Anteriorly primary muri aligned sub-parallel to anterior margin. Ventral surface and anterior and posterior marginal regions microreticulate. Surface of inner lamella with clusters of about 6 pores. Other internal features as for genus.

Comparisons. This species is most similar to Eucytherura ruggierii (Bonaduce, et aI., 1975) of the Adriatic Sea, from which it differs in its partially celate fossae and ventral microreticulation.

Distribution. Widely distributed in the south-west Pacific region: Late Oligocene to Early Pleistocene of DSDP Site 593; Middle Miocene and Pleistocene of DSDP Site 207A and 209, Early Miocene to Late P1eistocene of DSDP Site 592; Pliocene to Pleistocene of DSDP Site 208; Pleistocene of DSDP Sites 277, 282 and 284; Late Pleistocene of cores Sonne 36-61 and OSI 1-86/6GC3.