Discorhabdus
Classification: ntax_mesozoic -> Podorhabdales -> Biscutaceae -> Discorhabdus
Sister taxa: Biscutum, Discorhabdus, Similiscutum ⟩⟨ Boletuvelum, Chiastella, Crucibiscutum, Gaarderella, Gephyrobiscutum, Helicorhabdus, Jimenezberrocosoia, Seribiscutum, Sollasites
Distinguishing features: Circular, shields broad, usually without a prominent inner tube cycle; central-area typically narrow, may contain a spine.
Daughter taxa (time control age-window is: 0-800Ma) |
 |  |  |  | Discorhabdus biradiatus
Discorhabdus with gaps between distal shield elements
|
 |  |  |  | Discorhabdus corollatus
Small Discorhabdus with narrow central area from which a tall, narrow spine protrudes.
|
 |  |  |  | Discorhabdus criotus
Discorhabdus with a narrow, distal inner cycle, narrow/closed central area and distal shield sutures that kink near the shield's outer edge. Bicyclic rim image.
|
 |  |  |  | Discorhabdus hannibalis
Small (3-5 µm), with two closely appressed shields; proximal shield is wider than the distal shield, protruding beyond it and is at least twice as thick as the distal shield in side view.
|
 |  |  |  | Discorhabdus ignotus
Small to medium-sized Discorhabdus with closed central area that may or may not contain a spine.
|
 |  |  |  | Discorhabdus patulus
Placoliths with a tall flaring spine.
|
 |  |  |  | Discorhabdus striatus
Medium to large Discorhabdus with closed central area.
|
 | | | | Discorhabdus watkinsii
Species with low broad open protrusion and reduced proximal shield,
|
 |  |  |  | Discorhabdus sp.
Specimens not identified to species level
|
Taxonomy:
Citation: Discorhabdus Noël, 1965Rank: GenusType species: Rhabdolithus patulus Deflandre, 1954.Synonyms: Bidiscus Bukry 1969 - widely used in the literature
Cenorbiculus Burns 1976
Farinacci & Howe catalog pages: Discorhabdus + * , Cenorbiculus * , Bidiscus *
Distinguishing features: Circular, shields broad, usually without a prominent inner tube cycle; central-area typically narrow, may contain a spine.
Search data:
| Tags | LITHS: placolith, circular, CA: process, closed, CROSS-POLARS: rim-bicyclic, V-prominent, |
| Metrics | Lith size: 3->8µm;
Data source notes: size range of included species |
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 Maastrichtian Stage (100% up, 66Ma, in Maastrichtian stage). Data source: Total of range of species in this database
First occurrence (base): in lower part of Toarcian Stage (27% up, 180.4Ma, in Toarcian stage). Data source: Total of range of species in this database
Plot of occurrence data:
- Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
- Triangles indicate an event for which a precise placement has been suggested
- Neptune data: This is a higher taxon page so Neptune data is not plotted. See also: customisable plot Parent: Biscutaceae
References:
Bown, P. R. & Cooper, M. K. E. (1998). Jurassic. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 34-85. gs
Burnett, J. A. (1998). Upper Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 132-199. gs V O
Noël, D. (1965b). Sur les Coccolithes du Jurassique Européen et d'Afrique du Nord. Essai de classification des coccolithes fossiles. Éditions du Centre National de la Recherche Scientifique, Paris. 1-209. gs
