Test a low to flat trochospire, chambers globular and enlarging rapidly, four to six in the final whorl, sutures radial and depressed, umbilicus wide, occupying one-fourth to one-third of the diameter, periphery rounded, without keel or imperforate carinal band, peripheral outline lobate; wall calcareous, perforate, surface rugose, with irregularly arranged pustules and costellae, never meridionally aligned; primary aperture interiomarginal, umbilical, with tegilla filling the umbilicus and provided with both proximal and distal accessory apertures.
Archaeoglobigerina australis
Archaeoglobigerina blowi
Archaeoglobigerina bosquensis
Archaeoglobigerina cretacea
Archaeoglobigerina mateola
Archaeoglobigerina sp.
Archaeoglobigerina blowi
Archaeoglobigerina bosquensis
Archaeoglobigerina cretacea
Archaeoglobigerina mateola
Archaeoglobigerina sp.
Test planoconvex, with low trochospiral coil, later commonly with a change in plane of coiling so that the final whorl is in a lower plane, chambers inflated on the spiral side, somewhat flattened on the umbilical side, sutures straight and depressed, umbilicus wide and deep, periphery truncate, with a single keel at the spiral margin; wall calcareous, perforate, surface prominently papillate to hispid and lacking meridional costellae; primary aperture interiomarginal, umbilical, with a delicate tegilla, that commonly is broken out.
Test relatively large, up to 0.5 mm in diameter, with moderately high trochospiral coil, chambers globular to somewhat elongate as seen in edge view, enlarging gradually, four to six in the final whorl, sutures radial, depressed, umbilicus about one-fourth the test diameter, periphery rounded, noncarinate, peripheral outline lobulate; wall calcareous, perforate, surface with prominent pustules and rugosities but without regularly aligned costellae; primary aperture umbilical, provided with tegilla and with both proximal and distal accessory apertures.
Test with inflated triangular chambers in a low to flat trochospire, those of the final whorl radially elongate and ending in a tubulospine, sutures radial, depressed, umbilicus small, periphery rounded to compressed between tubulospines, peripheral outline strongly lobate and stellate; wall calcareous, perforate, surface with rugosities and costellae in meridional alignment; primary aperture interiomarginal, umbilical, provided with tegilla, and having both proximal and distal accessory apertures.
Test in low to flat trochospiral coil of rapidly enlarging globular chambers, biconvex, umbilicate, umbilicus occupying up to one-half the test diameter, periphery rounded, noncarinate; wall calcareous, perforate, surface with pustules, rugosities, and costellae in a meridional pattern; primary aperture interiomarginal, umbilical, with prominent tegilla and large proximal and distal accessory apertures.
Rugoglobigerina hexacamerata
Rugoglobigerina macrocephala
Rugoglobigerina milamensis
Rugoglobigerina pennyi
Rugoglobigerina rugosa
Rugoglobigerina spinosa
Rugoglobigerina sp.
Rugoglobigerina macrocephala
Rugoglobigerina milamensis
Rugoglobigerina pennyi
Rugoglobigerina rugosa
Rugoglobigerina spinosa
Rugoglobigerina sp.
Test with a low trochospiral coil, early chambers subglobular and inflated, later chambers slightly compressed, sutures curved on the spiral side and continuous with the peripheral carina, straight, radial, and depressed on the umbilical side, umbilicus wide, periphery with double-keeled imperforate carinal band; wall calcareous, finely perforate, surface strongly pustulose, adjacent pustules may coalesce into short costellae without distinct alignment, although resulting in a rugose surface; primary aperture interiomarginal, umbilical, elongate portici in the early chambers, later with distinctly protruding tegilla provided with accessory apertures.
Test in flat trochospiral, chambers enlarging rapidly as added, early ones globular, later chambers compressed to rhomboidal in section, imperforate carinal band or faint keel in the final whorl, sutures radial, depressed, peripheral margin rounded to truncate, peripheral outline lobulate; wall calcareous, perforate, surface covered with prominent pustules and costellae in meridional arrangement, less prominent on the final chamber; primary aperture interiomarginal, umbilical, bordered by an imperforate flap, those of successive chambers fusing into a tegillum having both proximal and distal accessory apertures.
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