Exochosphaeridium robustum Backhouse, 1988

Holotype: Backhouse, 1988, pl.26, fig.10a-b
Locus typicus: Perth Basin, W Australia
Stratum typicum: Late Valanginian-Early Barremian

Original description: Backhouse, 1988, p.85
Chorate cyst, body subsphaerical bearing at least 70 up to 100 processes. Autophragm composed of interlocking fibres; each fibre less than 0.5 µm or less than the maximum diameter, fibres drawn upwards and fused at a number of points to form fibrous processes. Processes rod-shaped, 8-19 µm long, 1-3 µm in minimum diameter, occasionally branching and distally truncate. Process distribution non-tabular, but small areas devoid of processes may indicate central intratabular areas. Paracingulum and parasulcus not indicated. Multibranched processes usually present at apex. Archaeopyle. Archaeopyle precingular, type P, operculum free.
Dimensions: Cyst body width of holotype 70 µm. Range of body width (16 specimens) 41(56)70 µm.

Affinities:
Backhouse, 1988, p.85: E. robustum is distinguished from E. truncatum by possessing thicker less tapered processes.