|Daughter taxa: (blue => in age window 0-800Ma)|
Small, lenticular or rhomboid outline. No distinct flange ending. Two normally inclined pores in central-area.
Similar to H. walbersdorfensis with wider bar and less distinct wing.
Medium sized. Flange ends in broad wing. Central-area with two normally oblique pores separated by narrow conjunct bar.
Similar to H. walbersdorfensis but larger and with larger openings.
Species of Helicosphaera with oblique, normally oriented, conjunct bar and blanket confined to central area
Distinguishing features: Miocene small to medium sized Helicosphaera species with wing ending flush with flange rather than terminating abruptly. Openings usually strongly oblique. Blanket confiend to central area, in xpl flange dark around whole coccolith.
Farinacci & Howe catalog pages:
Size: Coccoliths are usually smaller than those of the H.carteri group (5-8 µm vs 8-12 µm). H. stalis is smaller (cocoiths 4-6 µm) and H. waltrans & watkinsii larger (8-12 µm).
|Metrics||Lith size: 4->12µm;|
Last occurrence (top): near top of Messinian Stage (86% up, 5.6Ma, in Messinian stage). Data source: Total of range of species in this database
First occurrence (base): near base of Aquitanian Stage (8% up, 22.8Ma, in Aquitanian stage). Data source: Total of range of species in this database
Plot of occurrence data:
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