Lapideacassis


Classification: Coccolithophores -> Nannolith families inc sed -> Lapideacassaceae -> Lapideacassis
Sister taxa: Lapideacassis, Tintinnabuliformis,

Daughter taxa: (blue => in age window 0-800Ma)
0 spines; dome shaped; proximal collar
0 spines; elongate, tiered; proximal collar
1 spine; asymmetric cone
1 spine; symmetric cone, tiered
1 spine, with apical cross-shaped calyx;
2, asymmetric, spines; proximal collar
3, asymmetric, spines; proximal collar
3 spines sub-horizontal, evenly spaced; tiered; proximal collar
>3 spines; tiered; proximal collar
Specimens which cannot be assigned to any established species

Taxonomy:

Citation: Lapideacassis Black, 1971
Rank: Genus
Type species: Lapideacassis mariae Black 1971
Synonyms: Scampanella Forchheimer & Stradner, 1973 - has been used for forms with a single wall cycle, but regarded here as a junior synonym of Lapideacassis, following Burnett (1997);
Pervilithus Crux, 1981.
Notes & discussion: Rare and sporadic stratigraphic distribution, but K/T boundary survivor.

Distinguishing features: Hemispherical to cylindrical nannoliths, with walls constructed from one to several cycles of thin elements, enclosing a hollow central space; the nannolith tapers distally, and may have long apical spines or processes.
Species arranged here by number of spines.

Farinacci & Howe catalog pages: Lapideacassis * , Scampanella + * , Lapideacassis * , Pervilithus *


Morphology remarks: The numerous described species are based on numer of tiers in the body and especially on the number and arrangement of spines. It is likely the genus is oversplit but it is rare to find enough specimens to enable a useful study. In the table species are arranged by number of spines.

Search data:
TagsLITHS: nannolith-radiate, tubular, circular, RIM: tiered,
CSPH: not known, V-UNITS: none, R-UNITS: all, DETAILS: c-axes flaring,
MetricsLith size: 4->18µm;
Sources:
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 Priabonian Stage (100% up, 33.9Ma, in Priabonian stage). Data source: Total of range of species in this database
First occurrence (base): at base of Aptian Stage (0% up, 126.3Ma, in Aptian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:

Black, M. (1971b). Problematical Microfossils from the Gault Clay. Geological Magazine. 108: 325-327. gs

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

Crux, J. A. (1981). New calcareous nannofossil taxa from the Cretaceous of South East England. Neues Jahrbuch für Geologie und Paläontologie Monatshefte. 1981: 633-640. gs

Forchheimer, S. & Stradner, H. (1973). Scampanella, a new genus of Cretaceous nannofossils. Verhandlungen der Geologischen Bundesanstalt (Wien). 2: 286-289. gs

Kennedy, W. J. et al. (2000). Integrated stratigraphy across the Aptian-Albian boundary in the Marnes Bleues, at the Col de Pre _-Guittard, Arnayon (Drome), and at Tartonne (Alpes-de-Haute-Provence), France: a candidate Global Boundary Stratotype Section and Boundary Point for the base of the Albian Stage. Cretaceous Research. 21: 591-720. gs

Perch-Nielsen, K. & Franz, H. E. (1977). Lapideacassis and Scampanella, calcareous nannofossils from the Paleocene at sites 354 and 356, DSDP Leg 39, Southern Atlantic. Initial Reports of the Deep Sea Drilling Project. 39: 849-862. gs


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Lapideacassis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 18-10-2019

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Short stable page link: http://mikrotax.org/Nannotax3/index.php?id=798 Go to Archive.is to create a permanent copy of this page - citation notes



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