Late Cretaceous Biostratigraphy and Development of Heterohelicidae (Planktic Foraminifera)
- 1 January 1991
- journal article
- research article
- Published by JSTOR in Micropaleontology
- Vol. 37 (4) , 329-372
- https://doi.org/10.2307/1485910
Abstract
This paper presents a biostratigraphic and taxonomic analysis of late Cretaceous planktic foraminiferal Heterohelicidae from Tethyan and SW Atlantic sections. Albian and Cenomanian heterohelicids are small opportunists. Since the Turonian, an overall gradual increase in numeric importance and species richness can be observed, with iterative introduction of chamber proliferation. The early Turonian, mid Santonian and early Maastrichtian are periods of rapid speciation. Differences between localities are attributed to paleo-environmental conditions. A new genus, Laeviheterohelix, groups the smooth, microperforate heterohelicids. Four species and one variety are new: Heterohelix labellosa, Laeviheterohelix flabelliformis, Laeviheterohelix turgida, Pseudoguembelina hariaensis and Sigalia deflaensis rugocostata.This publication has 2 references indexed in Scilit:
- Cretaceous Planktonic Foraminifers—DSDP Leg 39 (South Atlantic)Published by International Ocean Discovery Program (IODP) ,1977
- Oxygen and Carbon Isotope Analyses of Tertiary and Cretaceous Microfossils from Shatsky Rise and Other Sites in the North Pacific OceanPublished by International Ocean Discovery Program (IODP) ,1975