Nannotax3 - ntax_cenozoic - D. lodoensis group Nannotax3 - ntax_cenozoic - D. lodoensis group

D. lodoensis group


Classification: ntax_cenozoic -> Discoasterales -> Discoasteraceae -> Discoaster -> D. lodoensis group
Sister taxa: D. brouweri group, D. pentaradiatus group, D. quinqueramus group, D. variabilis group, D. exilis group, D. musicus group, D. deflandrei group ⟩⟨ D. nodifer group, D. lodoensis group, D. multiradiatus group, D. araneus group, D. sp.

Daughter taxa (time control age-window is: 0-800Ma)
species are organised here primarily by number of rays
Discoaster pacificus
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.
Discoaster falcatus
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.
Discoaster saipanensis
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
Discoaster lodoensis
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.
Discoaster sublodoensis
Five (less commonly 6) rayed discoaster with a small stem on one side and sharply tapering, straight, pointed rays joined along half their length.
Discoaster mahmoudii
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.
Discoaster paelikei
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.

Taxonomy:

Citation: Discoaster lodoensis group - informal grouping
Rank: species group

Distinguishing features:
Parent taxon (Discoaster): Radiate nannoliths with each ray formed of a discrete crystal-unit, with the c-axes perpendicular to the nannolith surface.
This taxon: 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:
Lith size: 4->26┬Ám;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): at top of NP19-20 zone (100% up, 34.4Ma, in Priabonian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within NP8 zone (57.21-58.7Ma, base in Thanetian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:

References:


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D. lodoensis group compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 2-12-2023

Taxon Search:
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Short stables page link: https://mikrotax.org/Nannotax3/index.php?id=420 Go to Archive.is to create a permanent copy of this page - citation notes



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