Foraminifera
Taxonomy and identification

The classification of planktic Foraminifera used in this chapter was adopted from various sources (Loeblich and Tappan, 1988; Hemleben et al., 1989; Olsson et al., 1992). The page Order Foraminifera provides an overview of these species. In general, the following major informal groups can be identified: spinose species, non-spinose species, normally perforate species, and species without spines but with micropores.

The last group, which probably derives from Cretaceous ancestors (Olsson et al., 1992), has been called "microperforate". Micropores are not readily visible under the binocular microscope. In spinose species it is very difficult to see the spine holes after a species has undergone gametogenesis, which is the case in more than 99% of sediment-derived specimens. However, spines are usually supported by collar-like structures which after shedding give the surface a rough "pustulose" appearance.

Identification: Open in IdentfyIt the file Foraminifera.