SPIROPHTHALMIDIUM Cushman, 1927

 

 

Type species: Spiroloculina acutimargo Brady, 1884 (*344), p. 154; OD.

Spiropthalmidium Cushman. 1927 (*742), p. 37, 39 (nom. imperf.).

Spirophthalmidium Paalzow, 1932 (*2323), p. 99 (nom. corr.).

Test free, flattened, ovate to fusiform, periphery carinate, globular proloculus followed by undivided cornuspirine enrolled second cham­ber, and then by two chambers per whorl, planispiral, the chamber lumen narrow, that of successive chambers separated by plate-like shell material like that of the peripheral keel; wall calcareous, imperforate, porcelaneous; aperture rounded to ovate, at the open end of the final chamber. Holocene; cosmopolitan.