Fig. 6.

Schematic morpho‐molecular classification of Spumellaria based on ribosomal genes (18S and 28S rDNA) from Sandin et al. (2021).

A. Phylogeny showing molecular clades, taxonomic super‐families and environmental clades. Non‐supported nodes are reported by a surrounded question mark. Group with an asterisk denote changes in taxonomic nomenclature from Sandin et al. (2021) following the latest classification scheme for Radiolaria (Suzuki et al., ²⁰²¹). Colours correspond to molecular lineages (ML): blue = ML I, red = ML II, orange = ML III and green = ML IV.

B. Corresponding extent of the morpho‐molecular framework and main morphological features (including the presence and type of symbionts reported).

C. Scanning electron microscopy illustrations of typical silicified structures found in the four main spumellarian molecular lineages. All scale bars are 50 μm. Images courtesy of Miguel Sandin (Uppsala University).