Central nodule

Carinoportulae

 

Cingulum

In raphid diatoms, the thickly silicified area located between the proximal raphe slits. Often thickened, both in valve and girdle views. It is the site where the silica deposition vesicle deposits the first silica during valve formation.


Citations

Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms. Biology and Morphology of the Genera. Cambridge University Press, Cambridge, 747 pp.