N. steinmannii group


Classification: Mesozoic -> Braarudosphaerales -> Nannoconaceae -> Nannoconus -> N. steinmannii group
Sister taxa: N. steinmannii group, N. kamptneri group, N. abundans group, N. truitti group, N. circularis group, N. compressus group, Nannoconus - atypical, N. sp.,

Distinguishing features: Tapering nannoconids with narrow central canal (ct < wt).


Daughter taxa: (blue => in age window 0-800Ma) Granddaughter taxa
Very large, tapering (20-28 microns) (height ~3x width or more).

Tall, cylindrical (parallel sided) (height ~3x width or more).

Squat, pear-shaped.

Squat, barrel-shaped (similar height and width).

Pear-shaped to tapering

Taxonomy:

Citation: N. steinmannii group
Rank: species group
Notes & discussion: informal grouping first used here

Farinacci & Howe catalog pages: N. steinmannii group [no catalog entry yet]

Distinguishing features: Tapering nannoconids with narrow central canal (ct < wt).

Geological Range:
Last occurrence (top): at top of Campanian Stage (100% up, 72.1Ma, in Campanian stage). Data source: Total of range of species in this database
First occurrence (base): at base of Tithonian Stage (0% up, 152.1Ma, in Tithonian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:

Casellato, C. E. (2010). Calcareous nannofossil biostratigraphy of Upper Callovian - Lower Berriasian successions from the Souhern Alps, North Italy. Rivista Italiana di Paleontologia e Stratigrafia. 116(3): 357-404. gs


nannotaxlogo400px

N. steinmannii group compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 17-11-2019

Taxon Search:
Advanced Search

Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=10715 Go to Archive.is to create a permanent copy of this page - citation notes



Comments (0)

No comments yet. Be the first!

Add Comment

* Required information
1000
Captcha Image
Powered by Commentics