BOLTOVSKOYELLA Malumián and Masiuk, 1972

 

 

type species: Boltovskoyella argentinensis Malumián and Masiuk, 1972; OD.Boltovskoyella Malumián and Masiuk, 1972(*2001), p. 1.Test conical, spiral side strongly convex and umbilical side flat to concave, early whorl with up to six chambers, rapidly reduced to three per whorl, sutures curved and oblique, flush on the spiral surface, depressed around the umbilicus on the umbilical side, an ovoid to reniform supplementary chamber secondarily produced on each chamber around the umbilicus, periphery angular; wall calcareous, of calcite, by X-ray determination, optically radial, lamellar, hyaline, light brown in color, finely perforate on spiral surface but sutures, periphery, and umbilical surface imperforate, surface smooth but with small nodes on the umbilical surface; aperture a high interio­marginal arch, bordered by a lip. U. Eocene to L. Oligocene; Argentina.

 

Remarks: Assignment of this genus to the Asterigerinatidae follows the original description as being like the Asterigerinidae but having secondarily formed chamberlets. How-ever, Boltovskoyella is unique in the very high spire forming a parallel-sided cone and in the broad umbilicus, and the systematic position needs additional study.