Eucytherura elegantula, 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 : 212

Eucytherura elegantula n.sp.

Fig. 4 K-M

" Eucytherura elegantula" Millson, 1987 *: 283; pI. 15, figs 15 -18.

Etymology. Latin, very fine. Referring to the elegant ornamentation of the carapace.

Type material and dimensions. Holotype, OS 14065, adult right valve, length 0.34 mm, height 0.19 mm. Paratypes: OS 14066, adult left valve, length 0.35 mm, height 0.19 mm, OS 14067, adult left valve, length 0.35 mm, height 0.20 mm. All specimens are from the type locality.

Type locality and horizon. Lord Howe Rise, present day water depth 1389 m, DSDP Site 207A, core 11, section 4, interval 85-90 cm, Middle Eocene, Zone NP 16.

Diagnosis. A non tuberculate species of Eucytherura with weak posteroventral inflation. Uniformly reticulate with raised mural conjunctions and fine inwardly directed spines. Marginal and posteroventral regions bear long spines which may have clavate or secondarily spinose terminations. Anterior marginal rim has laterally projecting as well as forward projecting spines.

Description. Small sized, subtriangular in lateral view, weakly inflated and thinly calcified. Anterior margin convex with thin rim. Ventral margin sinuous tapering to short posterior margin dorsally. Dorsal margin straight. Posteroventral tubercle weakly developed, strongly spinose, spines usually clavate. Whole surface covered by a regular reticulum: muri with raised conjunctions and edged with fine inwardly directed spines. Long spines, with secondarily spinose terminations over marginal regions. Internal features where preserved as for genus. Radial pore canals and muscle scars not preserved.

Comparisons. This species is easily distinguished from most other species of Eucytherura by its distinctive spinose ornament and lack of tuberculation. It is similar to Eucytherura ginginensis (Boomer & Whittaker, 1994) from the Late Cretaceous Gingin Chalk of Western Australia. However, differences between these species can be seen in the nature and distribution of the external spines. For example, E. ginginensis has only marginal spines well developed on the anterior marginal rim, whereas E. elegantula has both laterally and anteriorly directed spines well developed.

Distribution. Known only from the Early to Middle Eocene of DSDP Site 207A.