Marginotruncana paraconcavata

Taxonomy

Original description: DIAGNOSE : Face dorsale plane ou legerement concave; face ventrale tres convexe. Loges tres étirées dans le sens de l'enroulement et bordées par un bourrelet sutural et périombilical sur la face ventrale. L'angle de raccordement entre les deux faces est supérieur à 60°

DESCRIPTION : Test calcaire hyalin perforé bilamellaire, g enroulement trochospiralé. Les deux faces sont fortement dissymétriques, la face dorsale étant plane ou 1égérement concave, la face ventrale fortement convexe ; l'angle de raccordement entre les deux faces oscille entre 60° et 80°.

Ouverture primaire intériomarginale ombilicale-extraombilicale. Bandeau carénal périphérique imperforé, comportant deux carénes trés proches. Les loges, au nombre de 4 g 6 au dernier tour, sont fortement étirées dans le sens de l'enroulement; sur la face ventrale, les sutures sont sigmoides et ourlées par un bourrelet sutural et périombilical se raccordant/t la caréne ventrale. Les sutures de la face spirale sont obliques et également ourlées par un bourrelet. L'ombilic relativement large est en partie recouvert par des expansions lamelleuses (<< tegilla >>) issues de la portion adombilicale des loges; il existe des ouvertures accessoires infraou intralaminales, mais non des ouvertures supplémentaires suturales.

Entries in the Catalog of original descriptions: Marginotruncana paraconcavata

Geological Range:
Last occurrence (top): within D. asymetrica zone (83.65-85.60Ma, top in Santonian stage). Data source: [copied from Chronos database]
First occurrence (base): within H. helvetica zone (92.51-93.52Ma, base in Turonian stage). Data source: [copied from Chronos database]

Plot of range and 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: Marginotruncana paraconcavata, synonyms included - Globotruncana sigmocostata; Marginotruncana paraconcavata; Marginotruncana sigmoconcavata;
• See also space-time plot :: Samples map :: Parent: Marginotruncana

Marginotruncana paraconcavata compiled by the pforams@mikrotax project team viewed: 25-4-2025 Taxon Search: Advanced Search Short stable page link: https://mikrotax.org/pforams/index.php?id=110335 Go to Archive.is to create a permanent copy of this page - citation notes

Add Comment

* Required information

Comment

Name

Email

Country

Captcha

Notify me of new comments via email

Remember my form inputs on this computer

I have read and agree to the terms and conditions

x

Insert Bullet List

Please enter at least one item.

Item:

Item:

Item:

Item:

Item:

x

Insert Numeric List

Please enter at least one item.

Item:

Item:

Item:

Item:

Item:

x

Insert Image

Please enter the link of the image

x

Privacy Policy

This policy contains information about your privacy. By posting, you are declaring that you understand this policy:

• Your name, rating, website address, town, country, state and comment will be publicly displayed if entered.
• Aside from the data entered into these form fields, other stored data about your comment will include:
  • Your IP address (not displayed)
  • The time/date of your submission (displayed)
• Your email address will not be shared. It is collected for only two reasons:
  • Administrative purposes, should a need to contact you arise.
  • To inform you of new comments, should you subscribe to receive notifications.
• A cookie may be set on your computer. This is used to remember your inputs. It will expire by itself.

This policy is subject to change at any time and without notice.

x

Terms and Conditions

These terms and conditions contain rules about posting comments. By submitting a comment, you are declaring that you agree with these rules:

• Although the administrator will attempt to moderate comments, it is impossible for every comment to have been moderated at any given time.
• You acknowledge that all comments express the views and opinions of the original author and not those of the administrator.
• You agree not to post any material which is knowingly false, obscene, hateful, threatening, harassing or invasive of a person's privacy.
• The administrator has the right to edit, move or remove any comment for any reason and without notice.

Failure to comply with these rules may result in being banned from submitting further comments.

These terms and conditions are subject to change at any time and without notice.

Comments

No comments yet. Be the first!

x