Distinguishing features: Parent taxon (Lapideacassaceae): Hemispherical to tall cylindrical nannoliths, with narrow walls constructed from one to several cycles of thin elements, enclosing a hollow central space; the nannolith tapers distally, and may have apical spines or processes. This taxon: Large hemispherical to tall cylindrical nannoliths with narrow walls constructed from one to several cycles of thin elements, enclosing a hollow central space; the nannolith tapers distally, and may have apical spines or processes. Protruding ledges often mark the junction of different cycles in the wall.
Daughter taxa (time control age-window is: 0-800Ma)
Distinguishing features: Parent taxon (Lapideacassaceae): Hemispherical to tall cylindrical nannoliths, with narrow walls constructed from one to several cycles of thin elements, enclosing a hollow central space; the nannolith tapers distally, and may have apical spines or processes. This taxon: Large hemispherical to tall cylindrical nannoliths with narrow walls constructed from one to several cycles of thin elements, enclosing a hollow central space; the nannolith tapers distally, and may have apical spines or processes. Protruding ledges often mark the junction of different cycles in the wall.
Morphology: The genus name Scampanella Forchheimer and Stradner, 1973 has been used for Lapideacassis forms with a single wall cycle, but is regarded here as a junior synonym of Lapideacassis following Burnett (1997). The group in general has had many species named, based on the number of spines present, but this may be strongly influenced by preservation, rather than representing any real taxonomic significance. The L. mariae (tall) and L. glans (domed) types are most easily recognised.
Lith size: 4->18µm; Segments: 6->14; Data source notes: size range of included species
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:
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
Black, M. (1971b). Problematical Microfossils from the Gault Clay. Geological Magazine. 108(4): 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. gsVO
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. gsVO
Lapideacassis compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 9-12-2021
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