1. Nannotax and Discoasters
Jeremy R. Young,
University College London

2. Nannotax 3 – launched sept 2013
Continuously developed since
e.g. added full coverage of extant nannos, Neptune database linkage, comprehensive rewriting of the code
Now about 17,000 images
2,700 taxa
many users (ca 1500 sessions per week, average session length 13 mins)
post INA 15 Farinacci Catalog has 4100 taxa (inc. 214 discoasters)

3. The main part of this talk was given using a live link to the Nannotax website not powerpoint slides.
Specifically it consisted of an overview of species level taxonomy of discoasters as presented on nannotax - with primary emphasis on the Neogene. The next
The other slides were briefly discussed

4. Neogene discoaster groups on Nannotax - as discussed using the website

5. Paleogene discoaster groups (modified from Romein 1979, Theodoridis 1984, Bown 2005 etc.),
as discussed using the website.
NB The D. araneus group was separated out following comments made during the workshop

6. Pliocene Discoaster cyclicity
Through the Late Pliocene there is strong climatic cyclicity, dominated by obliquity.
This is strongly reflected in Discoaster abundances
Succession of studies by Backman and Chepstow-Lusty
Chepstow-Lusty, A., Shackleton, N. J. & Backman, J Upper Pliocene Discoaster abundance variations from the Atlantic, Pacific and Indian Oceans: the significance of productivity pressure at low latitudes. Memorie di Scienze Geologiche 43,
Pliocene Discoaster cyclicity

7. Discoaster brouweri extinction
key documentation of synchrony in an event using cyclostratigraphy
Site 504
Discoaster brouweri extinction

8. Neogene discoasters overview (from Young 1998)
Is this a valid overview? How can it be improved?

9. terminology (from Young et al. 1997)

10. trends
reduced rays
reduced calcification
increased proximal-distal differentiation

11. Lambert 2005
Cahiers de Micropaleontologie
Kutei Basin
Indonesia
an alternative approach to nannofossil taxonomy
how can we describe the cloud of morphotypes within particularly 6-rayed bifurcate discoasters ?