## 4 Results
### Calcareous Nannofossils  
Calcareous nannofossils are common to abundant and show good preservation in almost all the samples. Results of the quantitative analysis are presented in Figure 6 and Table S3. The assemblages are dominated by placoliths that account for nearly 80% in some samples, among these the most represented genera are _Cococolithus_, _Cribrocentrum_, _Cyclicargolithus_, _Dictyoccites_ and _Reticulofenstra_. Other prominent genera are _Sphenolithus_ and _Discoaster_, while _Chiasmolithus_ and _Helicosphaera_ are less frequent. The _Cococolithaceae_ are mainly represented by the genera _Cococolithus_, _Chiasmolithus_ and _Ericsonia_. The genus _Cococolithus_ consists of _C. pelagicus_ and _C. epelagicus_. The abundance record of the group shows a slight increasing trend during the MECO and a peak of abundance in the post-MECO (>25%). The genus _Chiasmolithus_ is represented by the species _C. grandis_ and _C. solitus_, it occurs continuously showing a decreasing trend in the lower part of the MECO and an increasing trend in the upper part of the MECO just above the worming peak. _Ericsonia fornosa_ is continuously present showing rising abundances (up to 18%) in the upper part of the interval studied.  
Figure 5: Relative abundance of middle Eocene planktic foraminiferal genera and selected species form the Baskil section. The main ecological preferences are also indicated (see text for explanations). Magneto-biostr stratigraphy and lithost stratigraphy as in Figure 2.  
The _Noelierhabdaceae_ are represented by the genera _Cribrocentrum_, _Cyclicargolithus_, _Dictyococcites_ and _Reticulofenstra_. _Cribrocentrum_ shows increasing abundances in the middle part of the MECO. The genus _Dictyococcites_ is represented by the _species D. bisectus_ and _D. scrippsae_. _Dictyococcites bisectus_ firstly occurs in the lower part of the MECO, while _Dictyococcites scrippsae_ shows an abrupt variation in abundance (from <1% to >10%) in the lower part of the MECO, later on it shows wider numerical changes. The genus _Reticulofenstra_ comprises _R. daviesii_, _R. dictydoda_ (specimens with length between 5 and 14 \(\upmu\)m) and _R. umbilicus_ (specimens with length >14 \(\upmu\)m). Both _R. dictydoda_ and _R. umbilicus_ show a peak of abundance in the lower part of the MECO (up to >6% and >16% respectively), followed by a decreasing trend in the upper part of the MECO. _Reticulofenstra daviesii_ is very rare, sporadic, and not significant.  
The genus _Discoaster_ is represented by _D. barbadiensis_, _D. deflandrei_, _D. nodifer_, _D. saipanensis_, _D. tani_ and by specimens of rayed stellate discoasters with prominent lateral nodes. Overall, the genus exhibits a clear increasing trend from below the onset of the MECO up to the post-MECO, but highly fluctuating values are also observed.  
The genus _Sphenolithus_ is represented by the species S. funcatolithoides, _S. moriformis_, _S. obtusus_, _S. predistents_, _S. radians_ and _S. spiniger_. The genus shows a significant decreasing trend in the lower part of the MECO followed by a rise in the upper part. _Sphenolithus funcatolithoides_ disappears above the onset of the MECO, while _S. spiniger_ shows higher abundances starting from below the MECO, and a drastic decreasing in the uppermost part of the MECO followed by its disappearance in the post- MECO interval.  
The genus _Helicosplpara_ is represented by the species _H. compacta_, _H. euphatis_, _H. lophota_, _H. papillata_, _H. salebrosa_, _H. senitulum_ and _H. wilcoxonii_. The genus exhibits an increasing trend from the lower part of the MECO with a peak in abundance in its upper part.  
The holococciliths _Lanternithus minutus_ and _Zyghrablithus bijugatus_ show a rapid increase at the onset of the MECO with a peak in abundance in the lowermost part (respectively 17% and ~8%), followed by a drastic decrease in the upper part of the MECO and persisting low abundances in the post-MECO interval.