Nannotax3 - ntax_mesozoic - Quadrum svabenickae

Quadrum svabenickae

Classification: ntax_mesozoic -> Braarudosphaerales -> Polycyclolithaceae -> Quadrum -> Quadrum svabenickae
Sister taxa: Q. gartneri, Q. svabenickae, Q. bengalensis ⟩⟨ Q. intermedium, Q. eptabrachium, Q. octobrachium, Q. eneabrachium, Q. giganteum, Q. sp.

Distinguishing features:
Parent taxon (Quadrum): Stellate to cubiform nannoliths with walls formed from two cycles of 4-9 elements and no central opening or diaphragm. When cubiform, the elements are joined along sutures that go out to the mid-point of the 'cube' edges.
This taxon: Like Q. gartneri but with a central depression and elements that appear to be thickened at the edges.

Burnett 97 JNR Petra pl1-22a.JPG
Burnett1998-6-13-21.jpg
Lees_and_Bown2005-plate10-fig3.jpg
Lees_and_Bown2005-plate10-fig4.jpg
Lees_and_Bown2005-plate10-fig1.jpg
Burnett 97 JNR Petra pl1-22b.JPG
Burnett1998-6-13-22a.jpg
Lees_and_Bown2005-plate10-fig2.jpg
Thibault 2010 pl8-fig25.JPG

Taxonomy:

Citation: Quadrum svabenickae Burnett, 1997

Rank: Species

Taxonomic discussion: Orthography the specific epithet svabenickae is in honour of the nannofossil specialist Lilian Svabenicka since this is a female name ending in -a the correct form is svabenickae not svabenickiae

Farinacci & Howe catalog pages: Q. svabenickae *

Morphology:

A species of Quadrum which has an excavated central area and elements which appear to be particularly thickened at the edges. Differs from other species in the genus with four elements per face in possessing an excavated central area and thick outer corners. [Burnett 1997]

Size:

Search data:

Tags	LITHS: nannolith-radiate, quadrate, CA: closed, CROSS-POLARS: T-prominent,
Metrics	Lith size: 5->8µm; Segments: 4->4; Data source notes: illustrated specimens

The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Notes: FAD in UC15 in Tethyan realm (Burnett 1998)
Last occurrence (top): at top of Maastrichtian Stage (100% up, 66Ma, in Danian stage). Data source: Lees & Bown 2005 - consistently present to end Cret
First occurrence (base): within Coniacian Stage (86.26-89.77Ma, base in Coniacian stage). Data source: Burnett 1998

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
Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
Taxon plotted: Quadrum svabenickae, synonyms included - Quadrum svabenickae;
See also space-time plot :: Samples map :: Parent: Quadrum

References:

Burnett, J. A. (1997c). New species and new combinations of Cretaceous nannofossils and a note on the origin of Petrarhabdus (Deflandre) Wise & Wind. Journal of Nannoplankton Research. 19(2): 133-146. gs V O

Burnett, J. A. (1998). Upper Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 132-199. gs O

Lees, J. A. & Bown, P. R. (2005). Upper Cretaceous calcareous nannofossil biostratigraphy, ODP Leg 198 (Shatsky Rise, Northwest Pacific Ocean). Proceedings of the Ocean Drilling Program, Scientific Results. 198: 1-60. gs V O

Thibault, N. (2010). Calcareous nannofossils from the boreal Upper Campanian- Maastrichtian chalk of Denmark. Journal of Nannoplankton Research. 31(1): 39-56. gs V O