Collosphaera tuberosa Haeckel, 1887, p.97; Nigrini, 1971, p.445, pl.34.1, fig.1 (with synonymy)
Shell is a smooth-surfaced, lumpy sphere, having numerous subcircular pores, irregular in size and distribution (10 to 30 pores on a half-equator). Usually there is a rather larger pore where the shell indents (Nigrini, 1971).
Maximum shell diameter 103-159 mm (Nigrini, 1971).
C. tuberosa differs from Collosphaera orthoconus (= Collosphaera sp. A Knoll and Johnson (1975, p.63, pl.1, figs.1-2,7, pl.2, figs.4-8) by having the shell surface indented, whereas the latter form has numerous outward protruberances. It is distinguished from Buccinosphaera invaginata by lacking invaginations of the shell wall.
This species is found in late Quaternary tropical and temperate assemblages in the Pacific, Atlantic and Indian Oceans. Its morphotypic first appearance is probably synchronous and marks the lower limit of the Collosphaera tuberosa Zone. It is extant.
Additional illustrations can be found in Nigrini and Moore, 1979, pl.1, fig.1; Knoll and Johnson, 1975, pl.2, figs.1-3.