Includes species characterized by a cancellate surface with regular subhexagonal pore pits with pores at the centers (Pi. 4, Fig. 2). Thus, the surface of Zeaglobigerina appears distinctly cancellate in contrast to the hispid appearance of Globigerina (Globigerina). Although the surface ultrastructure of Zeaglobigerina is similar to Globigerinoides sacculifer, which is spinose during life, no indication of spines or spine bases was observed in Globigerina (Zeaglobigerina) species. We consider that the subgenus Zeaglobigerina is the ancestor of Globigerinoides saccullfer, which evolved via Globigerina (Zeaglobigerina) connecta and Globigerinoides triloba.

The subgenus Zeaglobigerina is largely a Neogene group, the earliest member being Globigerina (Zeaglobigerina) woodi, which gave rise through the Neogene to the following lineages (Text Fig. 8).

1. Gg. (Zg.) woodi -> Gg. (Zg.) connecta
 and -> Gg. (Zg.) brazieri

2. Gg. (Zg.) woodi -> Gg. (Zg.) druryi -> Gg. (Zg.) nepenthes
 and -> Gg. (Zg.) decoraperta -> Gg. (Zg.) rubescens

3. Gg. (Zg.) woodi -> Gg. (Zg.) apertura

The large umbilical aperture with distinct rim and coarsely pitted surface of "Globigerina" labiacrassata Jenkins is similar to that of Globigerina (Zeaglobigerina) woodi, suggesting close phyletic relations between these two forms.

Hofker (1977) proposed a monotypic genus Globoturborotalita with "Globigerina" rubescens as the genotype. Since this species has been included here as the latest and only living representative of the Zeaglobigerina lineage, Globoturborotalita may have priority. However, the phylogeny of Gg. (Zg.) rubescens is not clearly known, and detailed study of its evolution and the characteristics of its wall structure in relation Gg. (Zg.) woodi and related forms is still required.

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