Cushman and Brännimann, 1948

 

 

Type species: Ammoastuta salsa Cushman and Brönnimann, 1948; OD.

Ammoastuta Cushman and Brönnimann, 1948 (*814), p. 17.

Test compressed, ovate to flabelliform proloculus followed by second chamber growing in opposite direction, in an incipient tight coil, then uniserial, with a few small rectilin­ear chambers that increase in length as added, finally followed by elongate adult chambers with a slightly curved axis that each occupy about one-half the test periphery, the bulging basal part of the chambers enclosing the corresponding part of earlier adult chambers; wall agglutinated on an organic base, surface smoothly finished; primary aperture areal, a curved transverse slit near the midpoint of the apertural face, secondary cribrate open­ings on the bulging proximal end of the adult chambers. U. Cretaceous (Turonian to Santonian): Nigeria; S. Chad; U. Eocene or Oligocene: Colombia; Holocene: USA: Lou­isiana: Caribbean mangrove swamps in Trini­dad, West Indies; Panama; Ecuador, Brazil.

 

Remarks: The Upper Cretaceous species, Ammoastuta ^'nigeriana S. W. Petters report­edly lacks the median slit of the final cham­ber, but this may be a matter of preservation.