|Daughter taxa (time control age-window is: 0-800Ma)|
|species are organised here primarily by number of rays|
Large to very large (15-25 µm) rosette-shaped discoasters with prominent bosses on both sides and 8-19 short free rays that typically curve.
Large to very large stellate discoasters with a low boss on one side and 7-10 (commonly 9) curving rays joined along half their length with a ridge on one side.
Discoasters with 5-8 (normally 6 or 7) straight or curved rays joined through half their length and which then taper to a point. A central stem and distinct radial sutural ridges and depressions are visible in some specimens
Large to very large stellate discoasters with a central boss on one side and 5-7 (typically 6) curving rays joined along 1/2 to 1/3 their length with a ridge on one side.
Five (less commonly 6) rayed discoaster with a small stem on one side and sharply tapering, straight, pointed rays joined along half their length.
Distinctive stellate discoaster with 5 or 6 tapering free rays and a central area crossed by high inter-ray ridges that form a stellate boss.
Stellate discoaster with 5-6 (rarely 7) rays that taper to pointed tips. The central area is characterised by clockwise curving sutures on one side and a flower-like boss on the other. In 5-rayed specimens the rays can be slightly asymmetrical.
Distinguishing features: Stellate discoasters with curved rays; rays free for >1/3 of their length; rays without bifurcations or nodes; 5-10 rays
Farinacci & Howe catalog pages:Search data:
|Metrics||Lith size: 4->26µm;|
Last occurrence (top): near top of Priabonian Stage (86% up, 34.4Ma, in Priabonian stage). Data source: Total of range of species in this database
First occurrence (base): in lower part of Thanetian Stage (16% up, 58.7Ma, in Thanetian stage). Data source: Total of range of species in this database
Plot of occurrence data:
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