BioOne.org will be down briefly for maintenance on 17 December 2024 between 18:00-22:00 Pacific Time US. We apologize for any inconvenience.
How to translate text using browser tools
1 June 2014 Données nouvelles sur Rhapydionina Stache, 1913 et Fanrhapydionina n. gen., un groupe de Rhapydioninidae (Alveolinacea, Foraminifera) foisonnant en région périadriatique au Campanien-Maastrichtien
Jean-Jacques Fleury
Author Affiliations +
Abstract

New data about Rhapydionina Stache, 1913 and Fanrhapydionina n. gen., a bunch of Rhapydioninidae (Aveolinacea, Foraminifera) expanded in periadriatic area by Campanian-Maastrichtian time.

Rhapydionina gr. liburnica and its flabelliform variant Fanrhapydionina flabelliformis n. gen., n. sp. are the most outstanding components of a group, part of the Rhapydionininae subfamily, widely expanded in restricted environments of the carbonate platforms in north-occidental Mediterranean area by Campanian-Maastrichtian time. This group, like all Alveolinacea, comprises chambers divided into “primary chamberlets” by radial secondary partitions (“cloisonnettes”) perpendicular to the wall, hollowed out near the septum as to give way to a preseptal undivided volume (“preseptal passage”), crossed only by faint “preseptal buttresses”, and like all Rhapydioninidae a compact fabric in the axial part of chambers (“central endoskeleton”) irregularly crossed by some “secondary chamberlets”. The distinctive features of the group are a marked tendency to “uncoiling” (short involute scroll followed by a large “uniserial rectilinear part”: PRU in the text) and mainly a convex apertural “skull-cap”; the peripheral (“primary”) openings of this apertural riddle, oblique to the chamber axis, apparently isolate, in sections, the central endoskeleton from the rest of the test. The group appears and expands by the end of Cretaceous times. In Greece, two biozones, established on the distribution of members of the Rhapydioninidae family are distinguished: “CsB6”, partly Campanian-Maastrichtian in age, and “CsB7” partly Maastrichtian. The Rhapydionina Stache, 1913 species of the CsB6 biozone, called R. gr. dercourti as a whole, are equipped with small proloculus and keep a relatively large involute scroll. Among them, three new species are identified: R. bulbiformis n. sp. small in size, with a tiny proloculus, is assumed to be close to the origin of the group; R. dercourti n. sp., of medium size, with still a little proloculus, initial scroll relatively large, PRU essentially cylindrical to conical in shape, is well spread; R. fourcadei n. sp. close to the preceding, develops flattened chambers and a larger number of cloisonnettes, forecasting the Fanrhapydionina n. gen. way. Rhapydionina aff. liburnica mainly populates the CsB7 biozone, devoid of the previous species; the populations are close to the Slovene type of the species, specially because of their important uncoiling part, but are equipped with smaller proloculus, hardly larger than those of the CsB6 biozone. Moreover, the CsB7 biozone conceals Fanrhapydionina flabelliformis n. gen., n. sp., structurally identical to R. liburnica (Stache, 1889) but with a larger proloculus and a fan-shaped evolute part in the A generation. A CsB6 less specialized precursor (Fanrhapydionina aff. flabelliformis) proves individuality of this branch.

Jean-Jacques Fleury "Données nouvelles sur Rhapydionina Stache, 1913 et Fanrhapydionina n. gen., un groupe de Rhapydioninidae (Alveolinacea, Foraminifera) foisonnant en région périadriatique au Campanien-Maastrichtien," Geodiversitas 36(2), 173-208, (1 June 2014). https://doi.org/10.5252/g2014n2a1
Published: 1 June 2014
JOURNAL ARTICLE
36 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

KEYWORDS
Adriatico-Aegean carbonate platforms
biostratigraphie
biostratigraphy
Campanian-Maastrichtian
Campanien-Maastrichtien
espèces nouvelles
genre nouveau
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top