|Daughter taxa (time control age-window is: 0-800Ma)|
Flat, elliptical, formed from six crystallographic blocks divided by near-radial sutures.
Elliptical, narrow rim copmosed of many small elements, vacant central area
Small, elliptical with complex, weakly birefringent, central plate
elliptical, with axial ridges & 8-10 perforations; formed of 4 blocks with diagonal sutures
Small, elliptical with open central area spanned by broad transverse bar (dark at 0°)
Elliptical, non-birefringent in plan view, with 10-16 pores
Elliptical, narrow dark rim copmosed of many small elements, central plate of birefringent blocks
Small, elliptical holococcolith with a narrow rim and small, bright transverse bar spanning the central area.
Cavate elliptical holococcolith; bars define 6 holes - 2 at ends and 4 at sides
Small, cavate, only known from side-view, steep-sided base with short, narrow spine and median septum
Specimens which cannot be assigned to any established species
Distinguishing features: Elliptical holococcoliths with perforations.
Farinacci & Howe catalog pages: Holodiscolithus *Search data:
|Tags||LITHS: holococcolith, elliptical, hollow,|
|Metrics||Lith size: 2.5->6µm;|
Last occurrence (top): in upper part of Ionian Stage (75% up, 0.3Ma, in Ionian stage). Data source: Total of range of species in this database
First occurrence (base): in upper part of Danian Stage (63% up, 63.2Ma, in Danian stage). Data source: Total of range of species in this database
Plot of occurrence data:
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