none
Geological Time: Quaternary Holocene recent
holotype
View of a specimen of Pyrgo semicostata (Cushman, 1917)
The identification is based upon:
, : Cushman, J. A. (1917). A monograph of the Foraminifera of the North Pacific Ocean. Part VI. Miliolidae. Bulletin of the United States National Museum. 71(6): 1-108. Plate , Fig.