Lepideacassceae Terminology 2

Text Fig. 1 Terminology of Lapideacassaceae

Type Genus

Lapideacassis Black, 1971b

Remarks

Large cone-shaped nannolith has a narrow wall with proximal tier, collar, distal tier(s) and a cone. Elongated longitudinal laths make the wall, and ledges mark the junction of different tiers. The spines may or may not be present. The entire species is birefringent in plan and side view. Genera of Lapideacassaceae are distinguished based on the number of distal tiers. Species with two distal tiers are assigned to Lapideacassis (Black, 1971), whereas species with a single distal tier are assigned to Scampanella Forchheimer and Stradner (1973). Cenozoic species without any distal tier are assigned to Tintinnabuliformis Varol (1991). Burnett (1997c) considered Lapideacassis and Scampanella synonymous but not followed in this study because the separation of both genera assists for the better taxonomic organization.

References

Black, M., 1971b. Problematical Microfossils from the Gault Clay. Geological Magazine 108(4), 325-327.

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.

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

Varol, O., 1991. New Cretaceous and Tertiary Calcareous Nannofossils. Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 182, 211-237.