Discoaster signus


Classification: Coccolithophores -> Discoasterales -> Discoasteraceae -> Discoaster -> D. exilis group -> Discoaster signus
Sister taxa: D. exilis, D. cauliflorus, D. moorei, D. extensus, D. discissus ⟩⟨ D. bollii ⟩⟨ D. petaliformis, D. signus, D. apetalus

Taxonomy:

Citation: Discoaster signus Bukry 1971
Rank: Species
Taxonomic discussion: D. petaliformis is similar but has larger boss and shorter bifurcations. Theodoridis (1984) explicitly included such forms in his species concept for D. signus, however for reliable biostratigraphy is is probably best to have a discete label for the highly distinctive stratigraphically constrained forms.   

Distinguishing features: Similar to D. petaliformis but with longer bifurcations, and weaker boss. 

Farinacci & Howe catalog pages: D. signus * , E. signus *


Morphology: D. petaliformis is similar but has larger boss and shorter bifurcations. Theodoridis (1984) explicitly included such forms in his species concept for D. signus, however for reliable biostratigraphy is is probably best to have a discete label for the highly distinctive stratigraphically constrained forms.   

Search data:
TagsLITHS: nannolith-radiate, star-shaped, CA: process, CROSS-POLARS: 1ou, V-prominent,
MetricsLith size: 16->23µm; Segments: 6->6;
Data source notes: size from OD
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): within NN5 zone (13.53-14.91Ma, top in Serravallian stage). Data source: [JRY rough estimate]
First occurrence (base): within NN4 zone (14.91-17.95Ma, base in Burdigalian stage). Data source: [JRY rough estimate]

Plot of occurrence data:

References:

Bukry, D. (1971a). Discoaster evolutionary trends. Micropaleontology. 17: 43-52. gs

de Kaenel, E., Bergen, J. A., Browning, E., Blair, S. A. & Boesiger, T. M. (2017). Uppermost Oligocene to Middle Miocene Discoaster and Catinaster taxonomy and stratigraphy in the circum North Atlantic Basin: Gulf of Mexico and ODP Leg 154. Journal of Nannoplankton Research. 37(2-3): 215-244. gs V O

Maiorano, P. & Monechi, S. (1998). Revised correlations of early and middle Miocene calcareous nannofossil events and magnetostratigraphy from DSDP Site 563 (North Atlantic Ocean). Marine Micropaleontology. 35(235-255): -. gs

Theodoridis, S. (1984). Calcareous nannofossil biostratigraphy of the Miocene and revision of the helicoliths and discoasters. Utrecht Micropaleontological Bulletin. 32: 1-271. gs V O


nannotaxlogo400px

Discoaster signus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 22-10-2020

Taxon Search:
Advanced Search

Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=501 Go to Archive.is to create a permanent copy of this page - citation notes



Comments (0)

No comments yet on this page. Please do add comments if you spot any problems, or have information to share

Add Comment

* Required information
1000
Captcha Image
Powered by Commentics