pforams@mikrotax - Introduction to the Cenozoic Database



Objective

This part of the site aims to provide an authoritative guide to the biodiversity and taxonomy of Cenozoic planktonic foraminifera, a group of microscopic protists whose shells can be found in ocean sediments today and whose fossil record extends into the Jurassic Period (~170 million years ago). Their accurate identification is key to determining sediment age, reconstructing past climate and ocean conditions and past extinction and speciation events. This is especially so in the Cenozoic where planktonic foramnifera have played fundamental roles in both establishing the basic stratigraphy and in developing paleoceanography as a key modern science. This database is intended as both a working tool for specialists and an accessible reference source for anyone looking for information on planktonic foraminifera.

Paleogene vs Neogene Content

There are fundamental differences between the origins and rigour of the coverage of Neogene and Paleogene taxa and all users should be aware of this. Initially (January 2017 to August 2018) there were separate Paleogene and Neogene databases reflecting both this difference and the fact that there was no coverage of Oligocene taxa opening publication of the Wade et al. (2018) Atlas. Now that content from this atlas has been incorporated in the databases it is no longer possible to divide Neogene and Palaeogene taxa so all content has been merged into a single database.

Paleogene Content

To date, the Palaeogene database primarily has content developed by the Paleogene Planktonic Foraminifera Working Group, and published in the Atlas of Paleocene Planktonic Foraminifera (Olsson et al., 1999; Smithsonian Contributions to Paleobiology 85, 1-252.), the Atlas of Eocene Planktonic Foraminifera (Pearson et al., 2006 Cushman Foundation Special Publication 41, 514 p.) and the Atlas of Oligocene Planktonic Foraminifera (Wade et al., 2018 Cushman Foundation Special Publication 46, 524 p.). These are authoritative reviews and so the content for these parts can more or less be regarded as fully reviewed and reflecting the state of the art consensus of knowledge. This is especially true of the Oligocene since it is the most recent synthexis, and least true for Paleocene since this synthesis is now nearly 20 years old and in need of revision. Work from more recent publications has been incorporated in places but to date this has not been comprehensively checked.

Neogene content

There are special problems with constructing a database of Neogene planktonic foraminifera, since this fauna has not been systematically revised for a long time. This is in contrast to the Paleogene where working groups have produced definitive syntheses of taxonomy for the Paleocene (Olsson et al. 1999), Eocene (Pearson et al. 2006) and Oligocene (Wade et al. 2018). Since the Neogene was constructed from diverse sources, and was liable to be substantially revised, we decided to develop it initially as a separate module from the rest of the Cenozoic, with a first working version going live in late 2016. The site was developed and reviewed through 2017 and early 2018. Later in 2018 the Oligocene Atlas was published and content from it was then be incorporated into this website and the Neogene module will be merged into the main Cenozoic database.

Scope of the Neogene and Extant Database

Taxa wich originate in the Oligocene were included in the Oligocene Atlas (Wade et al. 2018), and so are covered in considerable detail. For the other taxa there is no equivalent source, but we have attempted to provide a reasonably comprehensive synthesis of Neogene and Extant planktonic foraminifera.

Taxonomy adopted for the Neogene

The taxonomy used here was derived as follows:
  1. The initial list was taken from the evolutionary synthesis of Aze et al. (2011).
  2. For the extant species this was supplemented by the taxonomy developed by SCOR Working Group 138 (Brummer & Kucera 2014, 2015).
  3. Additionally the revisions of Spezzaferri et al. (2015) and Wade et al. (2018) have been followed - notably including use of the genus Trilobatus.
  4. The classic reviews of Bolli & Saunders (1985) and Kennett & Srinivasan (1983) were compared to identify missing species.
  5. Streptochilus species were added from the work of Smart & Thomas (2007) and Resig (1989)
  6. Within Globorotalia (sensu lato) it was decided to informally subdivide species into lineages as generally accepted (e.g. Aze et al. 2011) but not to use the generic (or subgeneric) names, since: use of these has not yet been generally agreed, one of them (Hirsutella) is a junior homonym, and they are not used in the literature on the extant fauna.
  7. Taxa which originate in the Oligocene were removed from the list (as explained above).

Sources of content for the Neogene

The major content sources we have used are:
  1. Kennett & Srinivasan (1983) - images of taxa and taxon descriptions - with permission from Prof J. Kennett. Although there is a very large literature on Neogene planktonic foraminifera this is widely regarded as an outstanding synthesis.
  2. Aze et al. (2011) - the appendices of tabulated data on species, morphology, ecology, ancestor-descendant relationships, and ranges. Where appropriate we have cited both Aze et al. (2011) as the source for the data and indicated the original publications from which the data was derived by Aze et al. (2011).
  3. Postuma (1971) - drawings of taxa and thin sections of oriented specimens.
  4. Catalog of original descriptions - in a parallel effort we are extending coverage of the catalog database to include Neogene and extant taxa. Illustrations of type specimens are being added both from original publications and from new SEM images (ongoing project of Brian Huber). These images are automatically included in the Neogene pages as they become available.
  5. Neptune database occurrence records. As in the other parts of the pforams@mikrotax database records from the Neptune database are synthesised on the bottom of each page. For the Neogene the database of records is extensive so the occurrence records should be informative, although they inevitably do contain some incorrect or anachronistic data (see explanation).

Notes on some content types

  1. Ancestor-descendant relationships - Evolutionary trees are now drawn at the bottom of each genus page. In order to draw these the "most likely ancestor" needs to be recorded in the database for each taxon, together with a record of the source of the data and assessment of its reliability (this determines if a solid, dashed or dotted line is used to indicate the relationship on the chart). The data parimarily came from the figures in Kennett & Srinivasan (1983), cross-checked with Aze et al. (2011), and occasionally supplemented by data from other literature.
  2. Ordering of taxa on the taxon-tables - on most genera pages the species are arranged in lineage order, with ancestral species at the bottom and youngest species at the top. In some places genera are subdivided on the taxon-tables, these subdivisions are based on the evolutionary relationships and do not necessarily reflect accepted groupings.
  3. Distinguishing features - short statements of distinguishing features are given on the taxon-tables. Taken together with the images these should enable rapid understanding of the key differences between the taxa. These were essentially produced from the data compled elswhre on the pages. In particular in many cases it was possible to select key sentences from the text of the primary sources to use here, with more or less editing. It should be noted that these are not authoritative guides to species definitions. Where species are part of an evolutonary lineage then descriptions are typically a statement of the differences between the taxon and its ancestor and these are given in the the form "Like G. fohsi but..."

    To copy a table of distinguishing features text (1) select and the entire table in your web-browser (2) Copy into a texteditor of word-processor. If copying use Edit/Paste special.. and select paste as unformatted text.

Missing content

Major areas where content is currently missing include:

Comments and corrections

As explained this is a work in progress and so comments and corrections are especially welcome. Comments can be added at the bottom of any page and these will also appear on the recent comments page. ALL comments will be carefully reviewed and whenever relevant acted upon.

Jeremy Young, Bridget Wade, Paul Bown, UCL, Dec 2016 (updated Nov 2020)

References

Aze, T.; Ezard, T.H.G.; Purvis, A.; Coxall, H.K.; Stewart, D.R.M.; Wade, B.S. & Pearson, P.N.P., (2011). A phylogeny of Cenozoic macroperforate planktonic foraminifera from fossil data. Biological Reviews, 86: 900-927.

Bolli, H.M. & Saunders, J.B., (1985). Oligocene to Holocene low latitude planktic foraminifera. In: Bolli, H.M., Saunders, J.B. and Perch-Neilsen, K. (Editors), Plankton Stratigraphy. Cambridge University Press, Cambridge, UK, pp. 155-262.

Brummer, G.J.A. & Kucera, M., (2014). SCOR/ICBP 138 taxonomy and key to species of modern planktonic foraminfera v2.1. Chart distributed at TMS FNG meeting Texel, The Netherlands, June 2014: 1.

Brummer, G.J.A. & Kucera, M., (2015). Taxonomy of extant planktonic foraminifera, SCOR/IGBP WG138; August 2015. In: Spero, H. and Kucera, M. (Editors), SCOR/IGBP Working Group 138: Planktonic Foraminifera and Ocean Changes. Final Workshop & Short Course on Culturing Planktonic Foraminifera, California, pp. 8.

Kennett, J.P. & Srinivasan, M.S. (Editors), (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania, 1-265 pp. 

Olsson, R.K.; Hemleben, C.; Berggren, W.A. & Huber, B.T., (1999). Atlas of Paleocene Planktonic Foraminifera. Smithsonian Contributions to Paleobiology. Smithsonian Institution Press, Washington, DC, 1-252 pp. 

Pearson, P.N.; Olsson, R.K.; Hemleben, C.; Huber, B.T. & Berggren, W.A. (Editors), (2006). Atlas of Eocene Planktonic Foraminifera, Cushman Foundation Special Publication. Allen Press, Lawrence, Kansas. 

Postuma, J. (1971). Manual of planktonic foraminifera. Shell Group, The Hague. 406p.

Resig, J.M., (1989). Stratigraphic distribution of late Neogene species of the planktonic foraminifer Streptochilus in the Indo-Pacific. Micropaleontology, 35(49-62).

Smart, C.W. & Thomas, E., (2007). Emendation of the genus Streptochilus Brönnimann and Resig 1971 (Foraminifera) and new species from the lower Miocene of the Atlantic and Indian Oceans. Micropaleontology, 53(1-2): 73-103, 3 figures, 13 plates, 1 table.

Spezzaferri, S. & others, (2015). Fossil and genetic evidence for the polyphyletic nature of the planktonic foraminifera "Globigerinoides", and description of the new genus Trilobatus. PLOS one: 1-20.

Wade, B. S. , Olsson, R. K. , Pearson, P. N. , Huber, B. T. & Berggren, W. A. (eds) 2018a. Atlas of Oligocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication 46: 1-524.