|Daughter taxa (time control age-window is: 0-800Ma)|
Medium sized (height 6.2-9.2 µm) with short to relatively long spine that is slightly asymmetrical and dark at 0°. Square-shaped base with near-equidimensional quadrants and deep spine insertion.
Medium sized (height 5.0-6.7 µm) narrow sphenolith with a tall spine that is dark at 0° and conspicuously bright at 45°. Tall base with long upper quadrants that form part of the spine.
Small to medium sized (height 4.5-7.8 µm) with short spine, broad triangular shape (dart shaped) and wide base in which the lower quadrants dominate. Compound spine is dark at 0°.
Medium-sized sphenolith with a prominent apical spine, extending symmetrically from the basal part.
Large (height 7.5-19.8 µm) narrow sphenolith with a tall spine that is dark at 0°. Relatively tall base, with roughly equidimensional upper and lower quadrants. The spine indents deeply into the upper quadrants, appears to be monocrystalline, and is brightest at 45°.
Distinguishing features: Late Paleocene and Early Eocene sphenoliths with monocrystalline spines
Farinacci & Howe catalog pages:Search data:
|Metrics||Lith size: 4->20µm;|
Last occurrence (top): in upper part of Ypresian Stage (67% up, 50.5Ma, in Ypresian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Selandian Stage (71% up, 59.9Ma, in Selandian stage). Data source: Total of range of species in this database
Plot of occurrence data:
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