Foraminifera taxon details
From editor or global species database
Diagnosis Test biconvex, trochospiral, about three whorls visible on the spiral side, chambers broad and low, sutures oblique, thickened and flush, only the seven to eight chambers of the final whorl visible on the centrally umbonate umbilical side, sutures gently curved and radial, apertural coverplate secondarily formed over the aperture and innermost half of the chambers, the suture between the resulting chamberlet and primary chamber paralleling the test periphery, in rare specimens the coverplate may be present on the final chamber and cover only the proximal part of the aperture, periphery carinate; wall calcareous, of calcite by X-ray powder diffraction film, coarsely perforate except for the imperforate sutures and keel; aperture a low interiomarginal arch at the base of the apertural face on the umbilical side, with a narrow bordering lip, surface of test prominently beaded just above and below the aperture. M. Oligocene to M. Miocene; Germany; France; Belgium; Netherlands; Denmark. (Loeblich & Tappan, 1987, Foraminiferal Genera and Their Classification) [details]
From editor or global species database
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