FIGURES 18–23 in Morphological features and new description of the fossil species Thalassiosira dolmatovae (Bacillariophyceae)

FIGURES 18–23: Thalassiosira dolmatovae. SEM Fig. 18. Internal view of the valve with arrow showing occluded (?) areolae (OA). Fig. 20. Internal view of the valve showing labiate process (LP), copula (C), central fultoportula (CF) and marginal strutted processes (short white arrows) surrounded by 4 satellite pores. Fig. 19, 21, 23. External views of valves center showing opening of central strutted process (long arrows) and occluded (?) areolae (short arrows). Fig. 22. Enlarged fragment of Fig. 18 showing central fultoportula (CF), occluded (?) areolae (OA), and marginal strutted processes (short arrows). Figs. 18–22, #CAS 608382. Fig. 23, #CAS 60269.